5ta Edición del Simposio de Biomateriales Poliméricos

[00:01:23]Government of Mexico. Government of Mexico.

[00:01:36]Good morning. We extend a warm welcome and thank you for your presence at the fifth polymedical biomaterials symposium held in its modern virtual format. In this fifth edition of the symposium we will have the participation of researchers. with extensive experience in innovative topics from Spain and Mexico.

[00:02:03]Well, during these two days we will be presenting these speakers whose knowledge and experience have resulted in this field of innovation in the science and technology of polymeric materials.

[00:02:20]Well, we hope that this academic space will be ideal for strengthening this exchange of ideas, scientific collaboration, and discussion of these very relevant advances in this area. Well then, I'm going to give the floor to Dr. Víctor Raí. Go ahead, doctor.

[00:02:42]Thank you very much, Dr. Mayera. Well, good morning, university students, researchers and the general public. Thank you very much for your participation in this fifth edition of the Symposium. Um, for the mechanism to obtain the certificates of the event, it will be through a link that will be active, right?, during the presentation and yes, it will be announced in a moment later. Uh, for any questions or comments, you can contact us at the email address alonso. @unison.mx, uh, [email protected] MX or to the symposium email [email protected].

[00:03:22]Okay, now I'll pass the floor to Dr. Maer.

[00:03:26]Thank you very much, Dr. Reina. Well, to begin this event, I would like to allow Dr. Graciela Caire, our general director of the Food Research and Development Center, to address us with a few words. Dr. Graciela, please come in. Thank you.

[00:03:52]Thank you so much. Can you hear me okay?

[00:03:54]Yes, doctor, go ahead.

[00:03:58]Okay, very good. Well, good morning.

[00:04:00]Welcome to the fifth edition of the symposium on polymeric biomaterials, which represents a valuable opportunity to strengthen academic exchange and scientific collaboration in a research area that is strategic and has a great impact on technological development and the well-being of society. That is why we are brought together by a common interest in learning about, sharing, and discussing the latest advances in the science, technology, and applications of polymeric biomaterials, a field that continues to expand daily, pushes its boundaries, and generates innovative solutions for various sectors.

[00:04:47]I am pleased to mention that this initiative is organized by our Food and Development Research Center, along with the University of Sonora, and this year the University of the Basque Country and the Monterrey Institute of Technology are also participating.

[00:05:04]In our institution we are convinced that, sorry, [clears throat] sorry, sorry.

[00:05:17]that the generation of knowledge, [clears throat] innovation and the training of highly specialized human resources, are important and essential pillars for the progress of our society. Therefore, we are proud to be the host and also to be promoters of initiatives that favor the exchange of ideas, the [clearing of throats] building of strategic alliances and the dissemination of cutting-edge knowledge. That is why I also extend my special appreciation to the researchers, academics, students, representatives of higher education institutions and research centers, as well as our national and international guests who are joining us today at this important scientific meeting and who will share their experience and most recent findings in the fields of science, technology and applications of polymeric biomaterials. This participation of academics from Mexico and other countries enriches this space and strengthens the collaborative networks that are fundamental to facing the scientific and technological challenges of the present and the future.

[00:06:41]We appreciate that you have dedicated part of your valuable time to share your research with the academic community both in Mexico and abroad, who honor us with their presence today. I would like to comment that universal access to knowledge is the fundamental basis for the progress of our societies. In this context, one of the essential commitments of those of us dedicated to research is precisely scientific dissemination, which allows us to articulate humanistic, scientific, technological and innovation capabilities with the purpose [clears throat] of generating solutions or proposing alternatives to the strategic problems facing the country and our society. I would like to say that SIAD, in its capacity as a public center of the Secretariat of Science, Humanities, Technology and Innovation, the CCIT actively participates in the dissemination of research and scientific knowledge to society through this symposium. I must mention that this time we have more than 300 registered participants from countries such as Argentina, Bolivia, Chile, Colombia, Ecuador, El Salvador, Jamaica, Peru and Mexico.

[00:08:02]I hope that the planned activities will be highly beneficial, generate new opportunities for collaboration, and inspire future research that will continue to drive scientific and technological development in this important area of knowledge.

[00:08:22]Finally, I express my gratitude to the organizing committee, the participating institutions, the collaborating speakers, and all the people who have contributed their effort and commitment to make this fifth edition of the Biomeral Polymer Materials Symposium possible.

[00:08:43]Welcome, everyone.

[00:08:47]And now let's go to the opening ceremony.

[00:08:53]At 9:10 a.m. on Tuesday, June 2, 2026, I formally declare the fifth symposium on polymeric biomaterials open.

[00:09:07]Thank you very much and I hope everything goes well.

[00:09:13]Thank you very much, Dr. Caire, thank you for your message and the opening message of this event, and we also thank the center that supports us a lot with this event, which we are now holding for the fifth time. Well then, I'm going to allow myself to begin with the presentation of our first speaker, Dr. José Luis Pedrzinos.

[00:09:36]who is a researcher in the Department of Pharmacy, Science and Food at the University of the Basque Country. Well, to mention a little about Dr. Muñoz's career, Pedra Muñoz has been a member of the Nanocel research group of the pharmacy and technology laboratory and pharmaceutical department of the pharmacy and food science department of the University of the Basque Country. He belongs to Biorama, a research group of Naviocel here in Spain, of course, a member of the Research Center of the Bioengineering and Biomaterials and Biomedicine Network of the Carlos I Health Institute in Madrid, Spain. He has been a collaborator and joint laboratory for research and bioprinting, advanced pharmaceutical development of the Ucaray and QVA research center in Spain, and a professor of pharmacy and pharmaceutical technology at this university. His research has been, well, focused on biomedicine, nanotechnology, tissue engineering, and of course regenerative medicine.

[00:10:54]Well, you have developed several advanced systems for drug delivery, therapies applied to neurodegenerative diseases and, of course, rare diseases.

[00:11:06]Currently, his work is very focused on 3D bioprinting, both for organs and tissues and for the biomedical applications of these systems. He is currently the scientific director of Nobel Prizes, of what is uh Bask Pharma 40 and is also among the 2% most influential scientists uh according to data provided by Stanford University. Well, with all this background, let's give the floor to Dr. José Luis Pedrz Muñoz, who will present his paper on the design and evaluation of inks and bio-inks for 3D printing and bio-printing. Dr. José Luis, please go ahead. Thank you very much.

[00:12:01]Well, first of all, thank you for your presentation and also thank you for giving me the opportunity to be here among you and to be able to explain and share with you the research, developments and knowledge that our research group has developed over all these years.

[00:12:23]Uh, for me it is a pleasure to collaborate with the University of Sonora, with which I have even had some student exchanges and scientific collaborations. Hm. Well, going to the presentation, uh, uh, I would like to start by saying that three-dimensional printing and its biological extension, 3D bioprinting, represent two of the most disruptive technological advances of recent decades. Both are part of the broad field of additive manufacturing, a set of techniques that allow the construction of three-dimensional objects from digital models by deposition or solidification of the material layer by layer.

[00:13:06]Although the concept of fabricating three-dimensional objects from digital models originated in the 1980s, its application in the biomedical and pharmaceutical fields is recent, driven primarily by the convergence of engineering, biology, materials science, biopharmaceutics, and biomedicine. It is, therefore, a highly interdisciplinary area of research.

[00:13:34]Over the past decade, 3D printing and bioprinting have experienced exponential growth. In terms of scientific output, the number of publications related to these technologies has multiplied since 2010, driven by advances in biomaterials, bioinks and additive manufacturing systems applied to tissue engineering and regenerative medicine.

[00:13:57]In parallel, the global 3D printing market has shown sustained expansion, moving from primarily prototypical applications to the manufacture of customized medical devices, anatomical models, and functional biological structures. In the specific case of bioprinting, industrial and academic interest has grown significantly, with projected annual growth rates exceeding 20%.

[00:14:24]This joint development reflects increasing technological maturity and a clear trend towards the clinical and commercial translation of three-dimensional biofabrication.

[00:14:38]The main appeal of 3D printing lies in its ability to fully customize the geometry, composition, and functionality of the manufactured object. In the pharmaceutical field, this allows the production of personalized medicines such as pharmaceutical forms with doses adjusted to the individual needs of the patient, combinations of active ingredients or controlled release profiles.

[00:15:05]Beyond the pharmaceutical sector, 3D printing has become established in fields such as dentistry, orthopedics, and the manufacture of medical devices.

[00:15:15]3D bioprinting is a natural evolution of conventional 3D printing, in which the printed materials are not inert, but biomaterials and living cells. Its goal is to reproduce biological structures, from simple tissues to complex organs that emit the anatomical and physiological properties of human tissues.

[00:15:37]The 3D bioion has applications of enormous relevance in tissue engineering and regenerative medicine, but also in pharmaceutical research, where it is used to create three-dimensional models of human tissues and organs intended to test drugs, study diseases or evaluate toxicity. These in vitro models better reproduce human physiological conditions than traditional two-dimensional cultures or animal models, reducing costs, time, and ethical problems.

[00:16:12][suppressed scream] In bioprinting, the working material is called bioink, which is a mixture composed of cells, biomaterials and biochemical factors that provide natural, structural support and a biological environment to the cells. One of the critical challenges to achieving success in the fields of 3D printing and bioprinting lies in the development and manufacture of suitable bioinks. To achieve this, bio-inks must meet a series of criteria that can be divided into four sections: biological criteria, physical and mechanical criteria, chemical criteria, functional criteria, and practical and technological criteria.

[00:16:52]From a biological standpoint, the inks must be compatible with the living cells they contain and with the tissues of the recipient organ, and must not cause immunological, inflammatory, or toxic reactions. The cells must be kept alive during and after the printing process. This means that the bio-ink should not be exposed to extreme conditions of temperature, pressure, or radiation. Bioinks must allow cells to multiply and adopt the functions of the tissue that needs to be reproduced, for example, bone, muscle, and nerve cells. And finally, its composition must mimic the extracellular matrix of natural tissue, providing appropriate biochemical and mechanical signals to guide cell behavior.

[00:17:41]Regarding the physical and mechanical requirements, the bio-ink must have an optimal viscosity, fluid enough to be extruded by the printer, but firm enough to maintain its shape once deposited. It must flow in a controlled manner, under pressure. and regain its shape after deposition. In other words, it must maintain or exhibit thixotropic behavior.

[00:18:06]After printing, the bio-ink must retain its three-dimensional structure without deforming, collapsing, or dissolving prematurely. And lastly, it must be elastic enough to allow cell growth, but also rigid enough to support the shape of the tissue. It should be noted that these parameters vary depending on the type of tissue. For example, cartilage is more rigid than muscle, and bone has great hardness, or should have great hardness and rigidity.

[00:18:39]With regard to chemical criteria, the components of the bio-ink, polymers, gels, additives, must not release toxic substances or interfere with cellular processes.

[00:18:50]It must be able to solidify or stabilize through physical or chemical processes such as ultraviolet light, temperature, or calcium ions, without damaging the cells. And in some cases, the bioink must gradually degrade as the cells generate their own matrix. extracellular.

[00:19:09]This degradation must be biocompatible and non-toxic.

[00:19:14]Regarding functional criteria, it is essential that the bio-ink can be deposited accurately, forming reproducible and detailed structures, without clogging the injectors or producing irregularities. It must allow printing fine and precise structures, especially when it is necessary to reproduce microvasculature or interfaces between different tissues.

[00:19:40]Many bio-inks must be compatible with other types of bio-inks or scaffolds, which requires chemical and mechanical stability in contact with different substances and must allow the addition of growth factors, proteins or bioactive nanoparticles to promote differentiation and maturation of the printed tissue.

[00:20:02]Finally, with regard to practical and technological criteria, bio- inks must be able to be prepared reproducibly, stored without loss of properties, and have a reasonable shelf life. They must adapt to various bioprinting systems that we will see later, extrusion, injection, laser and allow adjustments in the printing parameters for application and for clinical or industrial applications. Bio-inks must be economically viable and able to be produced in large quantities with constant quality control. It should be noted that as the printability of the bio-ink is optimized, cell viability and bioactivity may be compromised, given that divergent conditions are created with respect to the natural extracellular matrix. Meeting this challenge involves overcoming the biofabrication window paradigm, seeking to balance ideal printability with maximum cell viability.

[00:21:11]Achieving this balance is complex and depends on multiple factors, which represents one of the most significant problems and challenges for researchers in this field. Adjusting these properties without compromising the functionality of bioinks is crucial to advancing 3D bioprinting and its application in creating functional tissues and organs.

[00:21:37]In the manufacture of bio-inks, biomaterials serve a dual purpose: providing processability for precise printing while simultaneously recreating a bioactive microenvironment that supports cell viability, proliferation, and differentiation.

[00:21:56]Since the emergence of additive manufacturing techniques, it has become clear that a wide variety of materials, both synthetic and natural, can be used in the design and production of bio-inks.

[00:22:10]Natural biomaterials include proteins and polysaccharides with intrinsic cell affinity, which can be found methacrylated, such as gelma, to allow their cytocompatible photocrosslinking.

[00:22:28]Fibrin and fibrinogen, for example, due to their fundamental role in angiogenesis and healing. Extracellular matrix components such as laminin or elastin, which improve adhesion and elasticity, are also common.

[00:22:45]Among the polysaccharides, alginate gels ionically with calcium and provides printability in the extrusion process.

[00:22:53]Hyaluronic acid and its methacrylate derivatives offer hydration and signaling.

[00:23:00]Chitosan confers cationic character and provides antimicrobial activity.

[00:23:06]Agarose and carrajane, in addition to good printability, allow for thermal gelation.

[00:23:13]One particularly interesting variant [clearing] is the decellularized extracellular matrix, processed from specific tissues, cardiac tissue, liver tissue, cartilage, dermis, and this allows the preservation of native tissue components, improving biocompatibility and biomimicry, although its main challenge is the variability between batches and the need to completely eliminate antigens, genetic material and edotonics. toxins.

[00:23:45]Synthetic polymers provide good control of morphology, degradation, and mechanical properties, although they lack biological signals, so they are frequently functionalized with peptide motifs, such as RGD.

[00:24:00]Polyethylol and polyvinyl alcohol are common.

[00:24:03]Thermoplastic materials such as polycarpolactone, polylactic acid, and glycolic polylactic acid allow for the creation of cellular scaffolds with high rigidity, on which a soft cellular bioink can be deposited, enabling the creation of hierarchical constructs.

[00:24:22]In parallel, functional additives and nanomaterials such as nanocellulose and clays like ponite can be added, which improve thixotropy and post-printing stability. Bioactive ceramics such as hydroxyapatite or calcium phosphate induce osteogenesis.

[00:24:42]Bioactive glasses promote mineralization and conductive nanomaterials such as graphene or graphene oxide facilitate electrical signaling in cardiac or neuronal tissues.

[00:24:56]The selection of biomaterials for the manufacture of bio-ink should be carried out considering especially the type of target tissue. Bio-inks derived from natural materials are suitable for soft tissues, but do not adequately replicate the biomechanics of harder tissues such as bone. To overcome this, synthetic materials such as polyclactone and inorganic elements are incorporated, with bioceramics standing out, particularly hydroxyapatite, as it is an essential component of bones.

[00:25:33]Bioactive molecules play a fundamental role in tissue regeneration. These molecules facilitate critical processes such as cell differentiation, migration, and proliferation.

[00:25:46]The incorporation of growth factors and biochemical signals into bioinks seeks to control cell behavior after printing, such as adhesion, survival, proliferation, migration, differentiation, and tissue assembly.

[00:26:06]To achieve this, the bio-ink must not only print accurately, but also present and release these molecules with the right doses, location, and timing.

[00:26:19]The most commonly used growth factors include, for example, VGF, angiotensin 1, PDGF, in order to enhance angiogenesis and vascular maturation. BMPS 2 A7 and sometimes VGF for osteogenesis. TGF beta and IGF1 for chondrogenesis.

[00:26:39]EGFPGF FGF2 in skin, HGF in liver, NGF, BDNF or GDNF in nerve, etc., etc. In addition to complete proteins, bioactive peptides, chemokines, small molecules such as retinoic acid, ascorbate, dexamethases and exosomes and extracellular vesicles, and matrix-derived matrikines can be used.

[00:27:07]These alternatives are more stable and economical, although they usually require anchoring or vehicles to achieve sustained signaling.

[00:27:18]Adding these molecules to scaffolds is relatively simple, with several strategies available for their incorporation, either in preformed scaffolds or during the manufacturing process, ensuring their presence from the start. In addition, techniques have been developed to control the timing and duration of its effect, adjusting the release profile to optimize its release.

[00:27:44]To regulate the release of these molecules, strategies such as encapsulation in nanoparticles or modification of the scaffold structure with various biomaterials are used.

[00:27:54]Controlled release can also be achieved through hydrogels, by adjusting the chemistry of synthetic polymers or the concentration and crosslinking of natural polymers.

[00:28:05]Another innovative approach is the use of microspheres loaded with growth factors incorporated into hydrogels for multimodal release. For example, in this case of the slide, what we have is a design in which a certain factor is encapsulated in microparticles using microfluidic technology.

[00:28:31]These microparticles are subsequently incorporated into the gel, in this case a light-cured gel, to obtain a scaffold that will be used for maturation, vascularization, and bone development. In this case, vascularization is a process that is initially needed and takes place with the rapid release of UGF. And maturation, that is, is a process that takes place more slowly and over a longer period, modulated by the release of morphogenetic factors.

[00:29:07]In this other example we have two different types of bioinks, using gelatin microparticles, in which a vascular bioink and an osteoinductive bioink have been developed, so that the vascular bioink allows the rapid release of VGF, while the osteoinductive bioink, as we see, controls the delay of the release of BMP2 and then a controlled release to produce maturation, induction and maturation. of the bone tissue.

[00:29:40]The incorporation of these signals should not compromise printability or viability.

[00:29:47]Effective concentrations depend on the tissue, the cell receptor, and the presentation strategy. That is, if we use soluble, immobilized, microencapsulated molecules, etc., etc. In three-dimensional culture, many factors act in the range of nanograms per milliliter, but their local bioavailability in the hydrogel and actual half-life are determined by matrix affinity, enzymatic degradation, and competition for ligands. Therefore, measuring release kinetics is key. Hm.

[00:30:23]as we see in this slide, and also validate its bioactivity, for example, the formation of endothelial tubes in the case of VGF, mineralization for BMP BMP2 or the expression of specific genes for certain activities such as, for example, TGF beta. Furthermore, it should be noted that excess or prolonged exposure to these factors can induce aberrant responses, such as fibrosis, ectopic calcification, and neoplasms.

[00:31:03]3D bioprinting has revolutionized the incorporation of biological components directly into ink, giving rise to what is known as bioink. In this context, the presence of cells is not just an addition, but an essential requirement for a material to be classified as bioink.

[00:31:28]The appropriate selection of cells, considering their origin and type, is crucial, especially in implantable tissue applications, where it can significantly influence the acceptance or rejection of the bioprinted construct by the recipient organism.

[00:31:44]The biological components of the bioink include living cells that can be either undifferentiated, such as mesenchymal stem cells, or differentiated, encompassing cell types such as epithelial, cardiac, and connective tissue cells, among others.

[00:32:02]Stem cells, including both adult stem cells and induced pluripotent stem cells, represent the core of the cells used in bioprinting.

[00:32:14]These cells are especially valued in the field of bioprinting because of their ability to transform into different cell types under specific culture conditions. This versatility gives fabric engineers the ability to create a wide variety of fabrics with precision.

[00:32:37]Cancer cells, for example, are commonly used as models to test technological advances in bioprinting and to create three-dimensional in vitro cancer models, which underscores their importance in disease simulation and treatment development. For example, the use of tumor cells from the patients themselves is very interesting, so that these tumor cells can be processed and included in three-dimensional models that are much more representative of the biology and evolution of the tumor, in which we can use or study not only the molecular biology of the tumor, but we can also study the response to certain types of tumors, to treatments, sorry. In this way we can optimize treatment, predict recurrences, and schedule second or third line treatments that allow us to improve the patient's quality of life and extend their lifespan.

[00:33:47]When choosing a 3D printing technology, it is advisable to analyze it taking into account three aspects: geometric resolution, cellular viability and/or functionality, and productivity and scalability.

[00:34:03]From there, each platform offers an optimal niche in combination with the bioink, its rology, its crosslinking mode, and with the type of cell or microtissue that is to be deposited.

[00:34:18]Currently there are multiple bioprinting technologies, but for reasons of time we will dedicate ourselves to analyzing only three of them because they are the most frequently used and that are extrusion bioprinting, drip bioprinting and laser-assisted bioprinting.

[00:34:40]Excision bioprinting uses pneumatic piston, microfluidic or screw systems to deposit bioink filaments, creating structures layer by layer.

[00:34:54]In the case of droplet bioprinting, we release precise drops of bioink using piezoelectric or thermal systems, allowing detailed control of the deposition.

[00:35:07]Laser-assisted bioprinting, on the other hand, is based on a laser-sensitive substrate that houses the bioink.

[00:35:14]Extrusion bioprinting stands out as the simplest and most prevalent technique in the field thanks to its affordable cost and ease of use, which are two fundamental aspects of its popularity.

[00:35:28]Droplet-based bioprinting is followed by laser-assisted bioprinting, occupying a less frequent but no less notable position.

[00:35:42]Furthermore, droplet and laser printing techniques offer superior resolution and accuracy compared to extrusion bioprinting.

[00:35:53]However, the associated costs and the technical complexity required to operate these advanced technologies limit their wider adoption. These factors suggest a balance between accessibility and performance in the choice of bioprinting technique, orienting the selection towards extrusion for general applications, while more sophisticated methods such as droplet and laser printing are reserved for applications that require greater detail and precision.

[00:36:24]Within the different bioprinting methods, bioinks must have a series of specific requirements for each of them.

[00:36:33]Thus, in all bioprinting techniques, the rheological properties of the bioinks play a crucial role in the success of the process. Factors such as cell density and type, chemical composition, and hydrogel concentration significantly affect these properties.

[00:36:52]Furthermore, each bioprinting method demands particular considerations in the design of the bioinks.

[00:36:58]Extrusion requires materials that flow easily during extrusion and solidify quickly once deposited, forming stable filaments. In droplet bioprinting, low viscosity and cell density bioinks are preferred to facilitate the formation of fine droplets that allow the creation of high- resolution structures, taking into account surface tension to avoid nozzle clogging and ensuring that gelation occurs post-position.

[00:37:29]Bio-inks for laser-assisted bioprinting must be adapted to the specificities of this approach, prioritizing sensitivity to the heat generated by the laser for adequate and efficient material transfer.

[00:37:43]This differentiated approach to bioink design underscores the importance of understanding and adjusting the rheological properties for each bioprinting technique, thereby optimizing results and expanding the possibilities for manufacturing complex tissues and organs.

[00:38:02]Finally, I would like to mention one issue related to the development possibilities of this type of technology, since bio-inks offer a very attractive business opportunity because they are located at the intersection of regenerative medicine, organ-chip models, and pharmaceutical development.

[00:38:24]Today the sector remains emerging and fragmented.

[00:38:29]Public estimates for 2026 range from approximately $88 million to $25 million, but almost all analyses agree on double-digit growth in the coming years and that Pharma and Biotec companies already concentrate about half of the demand thanks to the use of bioprinted tissues in Direct Discovery, toxicity and more predictive models than trials.

[00:38:58]In this context, the greatest value creation will not only be in selling hydrogels, in developing more reproducible, standardized bioinks adapted to regulated environments, because the evolution of the market will depend on solving key challenges such as batch-to-batch variability, scalability, safety and regulatory approval to move from current preclinical use to a much wider industrial and clinical adoption.

[00:39:25]Thank you very much for your attention.

[00:39:33]Thank you very much, Dr. José Luis, for your presentation. Okay, let's move on now to the question and answer session.

[00:39:41]Uh, I don't know if there are any already.

[00:39:44]Well, uh, I think there's the one by uh, Francisco Ibarra, right? He mentions what the challenges would be in trying to print these types of inks using spray jet techniques. Um, would it be possible to use this technique with these inks?

[00:40:03]Well, in principle, aerosolization could be used to print certain types of structures or certain types of scaffolding. However, in this case we should have some considerations. Well, it's important to keep in mind that aerosolization mechanisms introduce a large shear force into the biomaterial, and these high shear forces can influence cell viability. Hm. So this is one of the fundamental factors to consider in this case: optimizing the process so that these forces do not alter the viability of the cells.

[00:40:46]Furthermore, aerosol formation involves working with low viscosity bio-inks, so we should optimize the components to meet these properties, so that they do not affect the final result.

[00:41:04]Furthermore, the aerosolization technique is also important, since we should select this aerosolization technique from those available on the market to obtain a reproducible aerosol, an aerosol that can be deposited on the structure we are interested in and that does not affect cell viability.

[00:41:29]In this case, probably if what we want to generate are stable three-dimensional structures, we would probably have to combine several technologies. Hm.

[00:41:41]So aerosol printing could be a technique, let's say, somewhat similar to inkjet printing, what we've talked about as droplet printing. Uh, except that in this case the droplets would be formed by aerosolization and we could combine this aerosolization technique with other techniques, for example, extrusion or for example the use of thermoplastic materials such as polyprolactone or polylactic or co-glycolic, rigid structures and on these rigid structures aerosolize our bioinks with the cells. Hm. Probably in this specific case of this technique, it would be necessary to combine it with other types of technologies.

[00:42:24]Okay, thank you very much. [snort] Uh, Lerma Chan is also telling us, uh, what the main challenges are of working with SM-based inks.

[00:42:39]Well, that's a question, a very interesting question. Hm. We have done some work on this type of process.

[00:42:46]Uh, and well, as I mentioned before, one of the problems we're going to have is high variability.

[00:42:52]The processing is a long, tedious, complex process, and sometimes getting it to reproduce stably can be complicated.

[00:43:02]Furthermore, the processing will also depend on the type of tissue we are going to decellularize. Cellularizing a lung is not the same as cellularizing a muscle or a heart, so this type of technology will have to be adapted to the organ from which we want to obtain this cellular matrix. So, what we will have to do is optimize this process so that decellularization can be achieved through different protocols, and we will have to adapt our protocol to the type of organ and tissue from which we want to obtain this extracellular matrix. This extracellular matrix has multiple advantages from the moment we are going to use a material that is derived from the very organ we want to bioprint, which means it is more biocompatible, more biomimetic, some components will be preserved that help to improve the viability and biomimicry of our structure, but we will have to be very careful also to ensure that biological components that can induce immunological responses are very well eliminated. We will have to remove genetic material that could alter the biological response when we implant the organ or tissue. So these are very important issues to consider.

[00:44:24]What also happens here is that it is obviously a biological material, which each batch can come from a different individual or source, and this can mean that the final result may have a great deal of variability. So, in this case, perhaps one of the biggest challenges is harmonizing these processes, harmonizing the starting material through controls and exhaustive characterization so that the final result is as homogeneous and reproducible as possible.

[00:44:57][snort] Okay, doctor.

[00:44:58]Thank you so much. Um, Georgina Montesdioca has an interesting question. She says, "Good morning, could you comment on the temperature and humidity levels at which the printing processes are carried out?"

[00:45:11]Well, that 's another interesting question. We work in controlled conditions—in our laboratory, in the laboratory where we work—we work under controlled humidity and temperature conditions. Generally, we maintain the temperature between 20 and 22 degrees Celsius and a relative humidity of 60 to 70%. And it's true that we've observed that when the relative humidity and temperatures change, we can obtain different types of results and we can have problems in the printing because there are indeed materials that respond to temperature. If we are working with a temperature-dependent gelation technique, obviously the temperature changes in the environment will affect the characteristics of our final product. And humidity can also affect factors such as, for example, the flow and other characteristics of our bio-ink.

[00:46:07]So, yes, we do have to work under controlled humidity and temperature conditions.

[00:46:13]Higher or lower temperatures will depend on the characteristics of our biomaterials and, obviously, also on the geographical area where we are located. It's not the same to work or harmonize the temperatures of a laboratory in areas where external temperatures are high as in our area where temperatures are sometimes extremely low. But working at a temperature between 20 and 25 degrees Celsius and a relative humidity between 50 and 70% can be suitable conditions. Once we optimize these conditions, we obviously have to maintain them so that our processes and our bioprinting results are consistent and reproducible.

[00:46:59]Okay, thank you very much. So, as you can see, depending on the polymer, the conditions we will be working with will vary, right? And regarding this, Aarón de Jesús Rosas mentions what experiences he has had with the use of carrageenans.

[00:47:13]Specifically with carrageenans, we haven't used them in the area of ​​bioinks. Carrageenans, however, have been used... We have used them, for example, in the development of gels and sustained-release drug formulations. Hmm. But well, caraenanos are a series of biomaterials and natural biomaterials derived from algae that can behave very similarly to materials like alginate, like phosanos, etc., etc. So it's very similar to working with them. In this case, what we will have to control very well are [snort] the viscosities of our starting biomaterials and the bio-inks we develop. To do a good rheological characterization so that the techniques we select, whether it's an extrusion technique or a dripping technique, can offer us optimal results. And here I really want to emphasize that the rheological analysis of our biomaterials and the compositions of our bio-inks must be a very well-planned and very well-standardized process. And once we We have it standardized, so maintaining it over time ensures our results are reproducible. Hmm. It's advisable, for example, that once our bio-ink is standardized and the rheological study is done, before or after producing new batches of bio-inks, we proceed not obviously to a complete rheological characterization, but rather to define a series of parameters and specifications regarding radiology that we monitor over time to maintain our properties and the lucency of our scapholunate inks.

[00:49:09]Okay, thank you very much. Um, there's also a comment in the chat from Manuel Gutiérrez, who says that comparing this type of bio-ink with intelligent drug delivery systems based on nanomaterials, what would be their main advantages?

[00:49:28]Well, I think they are two different things. One thing is the release of drugs using nanomaterials that can provide us with nanoparticles, for example. And another case, another different aspect, is Bio-inks. Hmm. Well, we can incorporate these nanomaterials containing drugs into bio-inks. We've talked about biological factors and growth factors. So, in this case, it's important to select the biomaterials or nanomaterials appropriate to our growth factors to maintain stability, release properties, and sterility. And we can use, for example, gelatin to produce gelatin nanoparticles.

[00:50:19]We can use polylactic glycol to produce polymeric nanoparticles, and so on. And incorporate these into bio-inks. We'll have to develop these bio-inks in parallel to achieve the objectives we're pursuing. And here, we must consider one thing: these nanomaterials containing drugs or biological factors, depending on the proportion we incorporate into the bio-ink to obtain the desired effect. The construct, or the scaffold, can affect the rheological properties. Hmm. So, we not only have to characterize the rheological properties of the ink materials or the material mixtures in the inks, we will also have to do a rheological characterization of these bioinks with the nanomaterials or nanoparticles with the growth factors, because they can affect the behavior during bioprinting and therefore our final construct.

[00:51:29]Okay, thank you very much. There is also another question from Sara de los Ángeles Valle who asks how, broadly speaking, the degradation of the bioink influences tissue regeneration.

[00:51:43]It's a very interesting question because, obviously, we have to design bioinks to obtain scaffolds that we are going to incorporate into an organ and tissue.

[00:51:54]These scaffolds will contain cells, cells that have to integrate into that tissue, either directly because we use, for example, a chondrocyte, or because we use stem cells that will later differentiate. So, what does this imply? This implies that the scaffold has to have sufficient stability to to allow these cells to differentiate and integrate into the tissue while the new scaffold that will replace, or should replace, the old scaffold degrades.

[00:52:31]So, what do we have to do? Well, design our scaffold and its degradation rate based on the tissue into which we are seeking its integration.

[00:52:43]Obviously, the degradation at the skin level will not be the same as the degradation at the cartilage or bone tissue level. So, it is important to consider this factor and design our bio-ink and our scaffold to degrade according to the rate needed for the regeneration of that organ or tissue.

[00:53:06]Okay, thank you very much. Noemar asks how polycolactone can influence the release profiles of active ingredients.

[00:53:17]Well, in this case, I imagine we would also be talking about polycolactone containing active ingredients or biological factors that we will later include in the bio-ink.

[00:53:29]So, the Polycoprolactone, which is a thermoplastic material and a polyester, can obviously significantly influence the release of active ingredients. And here we will have to consider, for example, the molecular weight of polycoprolactone, just as, for example, the molecular weight of polylactic acid or glycolic acid can also influence the release profiles. So, generally, during tissue regeneration processes, these regeneration processes are not simple; they take time, and at each stage, a different phenomenon occurs that requires a different growth factor and a different release profile. Therefore, it is important to consider this regeneration process to select the biological products and the materials that allow us to encapsulate and release these biological products. We have seen that, for example, VGF needs to be released quickly. Therefore, we need to select a biomaterial that rapidly releases the drug or the biological factor. When we are looking for cell differentiation, uptake, or mobilization, we will need these biological factors at a more advanced stage, after the introduction of the scaphoid. in the body.

[00:54:57]So, in this case, for example, polycrapolactone or other polymers like PLGA might be more interesting. Why? Because they allow us to delay the release and control the release profile. And so here we can play with molecular weights, we can play with particle sizes, and modulate the release of these active ingredients, and by combining different biological factors with different polymers, with different nanoparticles containing different biomaterials, we can, let's say, sequence the release of these factors and adapt it as much as possible to the needs of the regeneration process we 're looking for.

[00:55:42]Okay, doctor, thank you very much.

[00:55:44]Our colleague here is asking what kind of bio-inks could be used as substitutes for articular cartilage in knees.

[00:55:56]In the case of cartilage, in our experience we have used different types of biomaterials.

[00:56:02]We have used alginates, [clears throat] we have used nanocelluloses, and here we have also incorporated some natural cartilage components into our bio-ink. We have Including, for example, dermatan sulfate, we have introduced condutin sulfate, and on some occasions, we have also introduced components such as nanocellulose.

[00:56:24]In our case, we have developed some bio-inks with the addition of nanocellulose because it considerably improves the rheological properties and printability of the bio-inks.

[00:56:39]The selection can be multiple. Hmm.

[00:56:42]But as I said, in this specific case, our experience has allowed us to select this type of biomaterial.

[00:56:53]Okay, thank you very much. I think there will be time for one more question.

[00:56:57]Diana Hernández mentions that there are some exclusion criteria for patients to be candidates for the use of bio-inks.

[00:57:07]Well, this is more of a clinical aspect that I don't control; that is, the implant follow-up aspect is more the responsibility of the clinicians. It is likely that some factors that imply the exclusion of potential candidates will need to be taken into consideration because, obviously, it will depend on the pathology, the percentage of damage, and the patient's clinical situation. But these are issues that a clinician will have to assess in each case. I imagine that, for example, in a fracture—imagine, for example, a bone fracture—well, in a bone fracture, let's say the bone damage can be of varying intensity; there can be minor or major damage. In this case, in the case of bone fractures, there is a great challenge in terms of the regeneration of large fractures. When the fracture is very large, then it will be necessary to consider whether it is really worthwhile to administer escazol or not, because sometimes regeneration is very complicated, and I imagine that in other cases and in other clinical situations, it can be very similar.

[00:58:15]Okay, doctor, thank you very much. Well, with that, we'll finish the questions. However, those that we did n't have time to answer, Dr. Pedras will be answering them via chat, right? I'll give the floor to Dr. Mariel.

[00:58:30]Thank you very much, Dr. Reina. Well, after that interesting chat, Dr. Pedraz, We still have many areas of opportunity to develop along these lines, and of course, we also invite our colleagues to get in touch with you. In fact, any questions or concerns can be addressed through our email addresses. And, of course, given your experience with a student from the University of Sonora in your laboratory, we appreciate that the Mexican presence is visible there in Spain, and especially in your lab. I, for one, would be delighted to receive emails, have my questions answered, and discuss future collaborations. We are available at any time.

[00:59:28]Thank you very much, Dr. Luis.

[00:59:31]Well, at this moment, thanking you also for this magnificent presentation, I would like to read the recognition that the Center for Research in Food and Development offers to Dr. Pedrás for his valuable presentation, " Design and Evaluation of Inks and Bio-inks for 3D Bioprinting." This was within the framework of the fifth symposium on polymeric biomaterials. [ Signature] Recognition to our director, Dr. Graciela Caire Juvera, Director General of the SAT, and it is scheduled for Hermosillo, Sonora, on June 2, 2026.

[01:00:19][sigh] Dr. José Luis Pedrz, thank you very much for being with us at this edition of the symposium.

[01:00:27]Thank you very much.

[01:00:28]Thank you for the invitation.

[01:00:32]Thank you.

[01:00:35]Well, now, after Dr. José Luis Pedrz's presentation, I will now give the floor to Dr. Víctor Reina to make the presentation.

[01:00:48]Go ahead.

[01:00:49]Well, as a reminder for those joining the broadcast right now, the certificate of participation in the event will be obtained by registering via a link, which will be activated at this moment and will be posted in the chat.

[01:01:04]If you have problems registering, we can provide the email address. The symposium's email is [email protected].

[01:01:12]Contact us and we will send you the attendance registration for today. Right? For those who have had problems. Well, once that's cleared up, let's move on to the second presentation of the day, which will be given by Dr. José Luis, uh, sorry, José Basilio Heredia, who is a professor and researcher at SIAP, coordinator of SAT, Culiacán branch, and a tenured research professor since 1996. He is a member of the National System of Researchers ( Level 3) and the Mexican Academy of Sciences. He was awarded the 2025 César Ordorica Falomir Scientific Merit Award by Confie Sinaloa. He specializes in functional foods, nutraceuticals, antioxidants, and natural products against chronic degenerative diseases.

[01:02:11]He is responsible for the pilot plant at CAT Culiacán and teaches courses in phytochemistry, bioprocesses, and food biochemistry. He has directed more than 60 theses and published more than 150 scientific articles, in addition to books and specialized chapters. He is a reviewer for scientific journals and research projects, both nationally and internationally, and maintains academic collaborations with institutions of Mexico, the United States, Canada, Europe, and South Korea. And today, we have a presentation titled " Smart Copolymers with Oregano Extracts as a Possible Adjuvant in Colon Cancer." I'll now give the floor to Dr. José Basilio.

[01:03:03]Thank you very much, Dr. Víctor. Víctor Reina from Unizón. I also thank Dr. Tomás Madera for this invitation. Good morning, good afternoon to everyone in Spain and wherever you may be listening and watching. I'm very grateful for this opportunity to share part of this research project being carried out at this branch of the Ministry of Science here in northwestern Mexico. Today, I'm going to present the results of a doctoral research project. Yes, by a researcher, currently a postdoctoral collaborator at this branch, Dr. Melisa García Carrasco, and the work is on smart copolymers with oregano extracts as possible adjuvants for the treatment of colon cancer.

[01:04:02]Um, in general, check [clears throat] here it is. The central idea of ​​this presentation is to show how we have generated a natural extract from the Mexican oregano plant, one of the more than 60 species cultivated worldwide, largely known for their culinary uses.

[01:04:36]In this work, we can generate this extract and, through biopolymers, impart properties of stability, protection, and biological potential by integrating these smart polymers. In particular, and this summary is very brief, we evaluated cationic phenylated matrices capable of carrying these compounds. We focused on the hydrophilic component of the oregano. Many of the studies conducted with oregano, including culinary studies, focus on the chemotypes of essential oils. We are even working with a bio-waste, an industrial biomass, using this other group of more hydrophilic compounds.

[01:05:27]And with this, integrating, forming these matrices, uh, how can we protect these bioactives during gastrointestinal transit, thus promoting their activity in cell models, especially the one we chose for this research, colon cancer?

[01:05:48]To begin, well, it's important to remember this problem that affects us worldwide, in some regions more than others. Yes. Colon cancer is one of the most impactful types of cancer. It develops through multiple cellular processes, among them oxidative stress, which can stem from multiple factors. Also, inflammation and the activation of certain pathways such as cyclosporine and tumor necrosis factors. These create a cellular environment that can contribute to tumor progression.

[01:06:26]Hence the interest in generating this research in the search for biomolecules that can have a similar effect to conventional chemotherapy, which we will discuss a little later. And this is done using these polymeric systems.

[01:06:47]Currently, the main cancer treatments include surgery, radiotherapy, and chemotherapy.

[01:06:55]He says, "Although these strategies have been fundamental in the Clinical practice is also known to have a large number of limitations, including the side effects that these generate. In the case of conventional chemotherapy, for example, these side effects can exist in healthy tissues, especially gastrointestinal and even hematological effects, in addition to therapeutic resistance that can occur in some patients.

[01:07:27]Therefore, it is not necessarily just about replacing current treatments, but about generating complementary alternatives, or " coaching therapies," as they are also called, that can increase effectiveness, reduce adverse effects, and contribute to a better quality of life for patients in these health conditions.

[01:07:56]In this context, we have been using Lipia Graviolens, this Mexican oregano, one of the most commercially available worldwide, for more than 12-14 years in our work, in addition to European oregano, which is origano vulgare, another species, another genus, even a different family, and all of them are commercially available, as I mentioned, in that way.

[01:08:23]Furthermore, as we know, that striking flavor they generate in various foods and especially in certain diets worldwide, well, this is an important source of bioactive metabolites, mainly we were saying essential oils and polyphenolic compounds.

[01:08:42]Among these compounds, in the hydrophilic polyphenolic extract, we can find a large number of very important flavonoids.

[01:08:53]Different reports argue their effectiveness in important biological activities, such as hesperidin, naringen, phloritin, and circimaritin, which have been related to antioxidant, anti-inflammatory, and anticancer activity, among others.

[01:09:12]However, one of the main problems with phenolic compounds is that although they have a high biological potential, they usually exhibit low solubility in aqueous media.

[01:09:23][snort] They are sensitive to changes in pH and temperature, and also exhibit low bioaccessibility.

[01:09:30]This means that a significant portion of these compounds can degrade before reaching the site where we seek that biological effect, as is the case with color.

[01:09:44]For this reason, nanotechnology is also a very important tool for us, as it is for many areas of research.

[01:09:52]These nanoformulations could allow us to protect these sensitive compounds, improve their dispersion in biological media, and promote a more controlled release.

[01:10:05]Yes, one of the challenges for the pharmaceutical or biopharmaceutical industry worldwide today, especially with derivatives of bioactive products, from plant sources, among others. Furthermore, when these are designed as intelligent systems that respond to typical pH and temperature stimuli, typical in processes such as cancer or even some enzymes present in biological microenvironments, they can give us that extra advantage through these copolymers.

[01:10:40]In this particular work we used pegylated and cationic polymeric systems.

[01:10:46]On the one hand, eh P or polyethylene glycol is widely used for its biocompatibility, its hydrophilicity and ability to improve the stability of delivery systems.

[01:11:00]On the other hand, cationic polymers, such as those derived from chitosan or PDAM, can interact with phenolic compounds through hydrogen bonds or celestoptatic interactions.

[01:11:13]These interactions are key to favoring the loading of the extract, this extract of interest in our oregano compound, in the matrix that we are choosing for that design.

[01:11:28]The methodology we use begins with obtaining the hydrophilic extract, this particularly phenolic one, of the Lipe graviolinis, obtained from the mountains of the state of Durango. Yes. In a town known as El Mesquitillo or in a village called Santa Gertrudis, this plant material was dried, pulverized, and subsequently subjected to ethanolic extraction.

[01:11:52]Then, the extract was incorporated into the polymer matrices by means of a loading process under agitation, thus allowing these compounds of interest to interact with the copolymers.

[01:12:06]Subsequently, the systems were characterized using different techniques. One of them, nuclear magnetic resonance, allowed us to confirm the structure of the eh copolymers that were synthesized.

[01:12:19]In the case of the system based on chitosan modified with PECMA, signals associated with both chitosan and PCECMA chains were observed, thus confirming the formation of the material.

[01:12:32]Furthermore, for the PE PEDAM system, the magnetic resonance characterization also allowed to corroborate the composition of the copolymer obtained by polymerization of this controlled radical synthesis. Ras.

[01:12:51]Another important technique was thermogravimetric analysis or TGA. Yes, this analysis allowed us to observe that by loading the phenolic compounds within the matrices, we could observe this modification through their thermal behavior, which suggests that the matrices not only serve as transport vehicles, but can also help protect the phenolic compounds, as seen in these figures, against the different degradation processes.

[01:13:26]In addition, we evaluated the stability of the systems in aqueous media. As these results show, free phonolic compounds tend to be more unstable over time, while pegylated systems maintain greater stability.

[01:13:43]This result is very relevant to us, as it can have implications for a biological application, given its functionality. It is not enough for the compound to be active; it must also be preserved during storage or even during its transit in the target organism, the organism of interest.

[01:14:06]We also determined the content of flavonoid compounds using liquid chromatography coupled with mass spectrometry, which allowed us to identify and quantify the specific compounds present in the extract and also in the loaded formulations.

[01:14:25]Among the main compounds observed were naningenin, spiridin, chloritin, and circaritin.

[01:14:33]A very important point is that after simulated digestion, the encapsulated systems retained a higher proportion of phenolic compounds compared to the free extract, as can be seen in this figure, in this table. This leads us to another important part of this work, which was the controlled release.

[01:14:53]The systems evaluated showed pH-sensitive behavior, which is fundamental, since the gastrointestinal tract has different pH values. For example, we know the stomach is acidic, while the intestine and colon have slightly basic conditions, closer to neutrality.

[01:15:13]The idea is that the system protects these bioactive compounds, phenolics in the case of oregano, in the gastric environment, favoring their release under more compatible conditions in the colon.

[01:15:27]Thus, the results indicate that woven matrices can protect compounds during gastrointestinal passage, promoting their availability in later stages.

[01:15:39]In particular, PEC PEDEN showed greater protection during the gastric phase, while the chitosan-based system modified with PECMA shows a significant release of these compounds under intestinal and/or colonic conditions.

[01:15:58]After this physicochemical and release characterization, the biological effect of the formulations was evaluated. For this purpose, two cell models were used, a line of colorectal adenocarcinoma cells or KQ2 and a line of normal colored fibroblasts known as CCD1.

[01:16:20]This comparison is very important, as it allowed us to evaluate not only the activity in tumor cells, but also the selectivity in healthy cells.

[01:16:32]These cells, for example, in healthy cells, the loaded systems we see here showed no cytotoxicity at concentrations less than or equal to 500 microg per milliliter. This is very important for us, as it indicates that the formulations can maintain an adequate safety profile in non- tumor cells, at least under the conditions evaluated in vitro.

[01:16:58]In contrast, cao cells, tumor cells, show significant antiproliferative activity, especially at 500 microg per milliliter, with a time-dependent effect. In other words, as the exposure time increased from 24 to 72 hours, the effect on the viability of cancer cells increased, suggesting that the progressive release of these phenolic compounds from the matrices may contribute to maintaining their biological activity for a longer time.

[01:17:39]Another relevant aspect that we carried out was the comparison against the five-floracyl. What is this compound?

[01:17:45]Well, it's a drug that is widely used in the treatment of colorectal cancer in chemotherapy.

[01:17:51]After 72 hours we were able to observe that our loaded nanoformulations showed comparable activity to five fluoroacyl in cancer cells, K2 cells, but had a lower cytotoxic effect on normal cells. This does not mean that the formulations will replace chemotherapy; however, they can and should be considered as adjuvant strategies with the potential to complement existing treatments. We also directly compared the two nanoformulations, seeing the advantages they had that were of interest to us.

[01:18:33]For example, the eh system based on chitosan modified with PECMA has as its strength the use of a biodegradable natural biopolymer with an affinity for phenolic compounds.

[01:18:44]In contrast, the PEC PEDIAM system offers greater molecular control due to its synthesis by RAV polymerization and its pH sensitivity associated with the presence of tertiary amino groups.

[01:18:59]In general terms, both systems exhibit loading efficiencies greater than 90%, sizes in the nanometric range, and the ability to release compounds under compatible conditions in an intestinal and/or colonic environment.

[01:19:14]Furthermore, they show antiproliferative activity in Caco2 and low cytotoxicity in colon fibroblast cells, supporting their potential as selective platforms.

[01:19:27]From a design perspective, these materials can be considered as intelligent pH-sensitive systems.

[01:19:37]In a possible scenario where they can be administered orally, the formulation should protect the phenolic compounds in the stomach, prevent their premature degradation, and thus what we are most looking for is to promote a controlled release at the colon level. This would allow for an increased local concentration of bioactives, reducing unnecessary exposure in other tissues.

[01:20:02]Therefore, the main contribution of this work is to demonstrate that the phenolic compounds of Mexican oregano can be stabilized and enhanced by conical matrix elements.

[01:20:16]We observed that encapsulation improves its stability, protects its antioxidant activity, promotes its controlled release, and allows us to observe an important antiproliferative effect in these selected colon cancer cells.

[01:20:32]In conclusion, we observe that these systems represent a promising strategy for the development of bioactive formulations of a nutraceutical, even supplemental or biopharmaceutical type, which is the purpose of all research in this context, especially with bioactives of natural origin with possible application as co-adjuvants in tail cancer.

[01:21:01]Even so, we must consider that these studies correspond to in vitro research, which requires further research with preclinical and clinical trials, vidity availability studies, safety studies and regulatory evaluation, obviously before considering a clinical application.

[01:21:26]With that said, I greatly appreciate your attention, but not before sending my thanks to the research group involved in this project.

[01:21:37]Starting with Dr. Melisa García, she is a researcher in the postdoctoral stay program for Mexico here at SEAD, in the Culecán sub-office. to Dr. Ángel Icea Clavería of the National Technological Institute of Mexico in Tijuana campus, to Dr. Lorenzo Antonio Picos Corrales, also to the work group that I rely on a lot in this work that we carry out in the functional and nutritional foods laboratory here at the Culiacán sub-headquarters. And I'd like to thank everyone for attending, and the organizing committee again for this opportunity to share. Um, excuse me briefly, here's my part of the research we carried out on this topic with experts in these lines of research. I look forward to your comments. Thank you.

[01:22:35]Thank you very much, Dr. José Basilio.

[01:22:37]Heredia. Thank you for this interesting and very complete talk/presentation that you have given us at this symposium and about this line of research that you are developing there at the Culiacá sub-headquarters.

[01:22:52]Well then, let's move on to the section for questions, comments, observations, everything we have to express here in this forum. To everyone who participated, if you have any questions, you can post them here in the chat on the different platforms where we are broadcasting.

[01:23:15]Well, Dr. Basilio, if you'll allow me, I'd like to take this opportunity to ask a question regarding what you mentioned about the polymeric matrix you 're using.

[01:23:28]The fact that the bioactive compound, the extract that is inside this biopolymeric matrix, has had the opportunity to show, I think it did, but could you tell us about the stability that is achieved in the biomaterial, how long can it maintain those required characteristics, doctor, before moving on to the biodegradation process that occurs? Can you tell us something about that, please?

[01:24:05]Yes, doctor. In this work, the study was carried out over a period of 24 to 72 hours, a time very similar to what could be expected in a conventional drug treatment with that frequency with which it should be administered to people already compromised in their state of health. So, it was a simulation of what would happen under those conditions.

[01:24:37]Okay. Okay. Yes. And above all, the fact that you were able to achieve this copolymerization with healthy chitosan is very interesting. Hey, why look for a healthy kit? No, I don't know if you were curious enough to use it and no other police officer saw it. Yes, especially because of the support in the literature, doctor. Uh, this was a doctoral project. So, we had, uh, there was already a precedent in previous work in collaboration with Dr. Licea in Tijuana and a continuation of these activities. Uh, there's a lot of information about the insurance, about a matrix that's very, very easy to work with. Yes, above all we wanted to evaluate the interaction that already exists with this type of metabolite of interest to us, the phenolic compounds. We work with different phytochemicals in this research group, alkaloids, terpenoids, but polyphenols and especially derivatives of this biomass represent a very large area of ​​interest for us. In addition, the agricultural sector in this region of the country generates a large amount of biomass in the fields, which we are looking for ways to not only obtain and extract with green technologies, but also to protect. Yes, we are trying to take that next step through these projects a few years ago, especially with these working interactions with experts in the area of biopolymers.

[01:26:20]Mm. Yes, yes, of course. Well, we have comments from the audience here, and our colleague Jorge Mercado from CTV sent them a very cordial greeting; he's very well known there in this coordination at the CTO. Thank you very much, Jorge, thank you for being here with us. Okay, we have another question from Noemí, Jardón. The proliferative mechanism of action in biological compounds could be attributed to an antioxidant or anti-inflammatory action.

[01:26:56]Any comments, professor?

[01:26:59]Yes. From the research we've conducted with different polymers, from matestrine to various rubbers at the micro or nano encapsulation level, we've seen that the compounds, especially these care products, can have dual activity. These phenolics, many of them flavonoids, which we have focused on quite a bit, and well, our matrix of study of oregano for so many years now.

[01:27:26]Yes, we are checking that this action may be, firstly, an antioxidant action, as most phenomena are oxidative stress, which must be regulated. Let's see a homeostasis in the case of the uh to avoid that triggering of that particular pathway when we talk about the induction in response to stress. So, first there's that antioxidant action, but in the same way they can induce the action of an inflammatory process to modulate it, right?

[01:28:07]Not to stop it completely, but to prepare the organism, to prepare the cells to confront any situation in which that tissue, that organ, is exposed.

[01:28:19]Perfect. Excellent. Excellent. Very good, professor.

[01:28:24]Complementary, one method of the other.

[01:28:26]Yes of course. Well, Isabel Jiménez, one of your students in Culiacán, also sends her greetings.

[01:28:35]Perfect. We have another comment from Manuel Gutiérrez. What influence does the type of positive or negative charge of the polymer's functional groups have on the encapsulation capacity of the bioactive? I think that's an interesting question. Yes, it is very important, very important, since the liberation itself will depend on this, which is one of the characteristics we are looking for, beyond stability as well. So, in this project, we developed it further, focusing on the bioassay aspect, but the load, how do we define it? Uh, we've even been working on it with eutectic mixtures, right? With eutectic solvents. We have some projects there for wound healing, which is another collaboration we have with Dr. Josué Mota from CFAT in Querétaro, at UNAM. So, these types of loads, in this case, Manuel Gutiérrez, a very important question because depending on how you generate that matrix, that's how the answer you get in the test you're carrying out will directly be. So, if you have to evaluate it, it depends on what your target is, what the objective is, whether it's a cell or some modulation of a biological system.

[01:30:04]Excellent. Very good. Very good. Yes, we are familiar with the work that Dr. Mot has done at CFAT, and it's very interesting that there is this collaboration between our center and other centers, especially with UNAM. Very good, very good. And we also have greetings from Andrés Pacheco, another student who has also been there in Culiacán.

[01:30:27]And well, here in our chat, our colleague Dr. Victor Reina also wants to ask a question. Are gastric simulations considered, or only the variables of different pH levels and temperatures? What are these tests like, doctor?

[01:30:51]We perform gastric simulation precisely with that, Dr. Victor, uh, only with the variables of pH and temperature, which are related in many cases to events of tumor progression, right? the formation of that distortion of those cancerous cells, that change in pH, that change in temperature, and based on that, it's as if we expose these charged polymers and try to make that correlation, nothing more, and at that level.

[01:31:24]Okay. Okay. Very good, very good. Well, taking advantage of this, doctor, we have also considered introducing these extracts, for example, into other types of biomaterials. We're talking about nanofibers, we're talking about processes like electrospin or electrospray, which is also another way of encapsulating. I don't know, I don't know if the group has already considered it. We have n't done it yet, doctor. Um, as I was saying, uh, this line of research is of great interest to us in terms of collaborations. Hopefully, as is always intended with these events, these symposia, these approaches will be made. Uh, we currently have all that knowledge more developed in the phytochemical part, in the green extraction part, uh in the part of polymers, biopolymers in particular. We are new, we don't depend much on collaborations like the one with you, doctor, we can do with Dr. Victor and the other collaborations I already mentioned.

[01:32:29]So, we are very interested in being able to protect, to stabilize, to carry in a programmed way, why not say it, these bioactives, since without this we run the risk of even, and I'm going to dare to say it, there are no nutritionists in the session, but many times a diet or a food plan is not enough if your bioactive compounds that you seek to have in your regimen will not be able to be absorbed, will not be able to be metabolized and deliver that function. And don't even get me started on the supplements, right? This huge global industry is growing in enormous quantities because of the way it is marketed. However, how much of that can we actually take advantage of? Can our system really be efficient? And the other thing that I do n't want to go into too much detail about is the probiotics part, which is so strong right now, this whole idea that with this it's going to change your microbiota and it's going to have an impact on your health, well, we're really sure that they're going to be absorbed, that they're going to generate, to perform that function. I feel that this topic, doctor, interests me greatly as well, and I want to continue working on the subject of biopolymers and these methodologies. With this I close this part, what you mentioned, uh, very willing and to collaborate wherever those methodologies, those systems are found and through them, right?, the training of human capital that we can carry out on that path.

[01:34:09]Well, it was very welcome to be here in the Hidalgo sub-city, where we are counting these Incas. Well, we're going to close with the presentation by Dr. José Basilo Heredia, and now our colleague Dr. Víctor Reina has the floor.

[01:34:30]Go ahead, doctor.

[01:34:33]Thank you very much, doctor. Well, with this we will conclude the presentation of Dr. José Basilio, granting him recognition for his valuable participation.

[01:34:45]In this case, I will allow myself to read it.

[01:34:50]The Research, Food and Development Center grants this recognition to Dr. José Basilio Heredia for his valuable participation with the work entitled Intelligent Copolymers with oregano extract as a possible adjuvant in C. cancer presented at the fifth edition of the symposium on biomaterials and polymers, a document issued in the city of Hermosillo, Sonora, Mexico, today June 2, 2026 and is signed by Dr. Graciela Caire Juvera, general director of Leo la palabra al dr. Mayera, por algunos asuntos.

[01:35:28]Thank you so much. Thank you. Thank you, doctor. Basil. Well, [clears throat] with this we will conclude the presentations we have had today, which we hope you have enjoyed and of course we invite you to join us tomorrow starting at 9 a.m.

[01:35:49]Hermosillo, Sonora time, 10 a.m.

[01:35:52]Mexico City time. Well, I'm also going to give the floor to my colleague Víctor Reina because he has some very important messages. Go ahead, doctor.

[01:36:02]Thank you very much, and just a reminder to those who had any issues or couldn't attend the session, it will be available on Facebook Live at the Seat Sens City address for those who had that problem, right? And also for those who had doubts or have any comments, you can send them to us at [email protected].

[01:36:27]Well, with that we'll be concluding today's session and we invite you to continue tomorrow where we'll have the presentations, which will be the same as today, there will be two. Uh, number one, the first one would be antimicrobial nanomaterials engineering, multifunctional strategies to combat resistant pathogens, which will be led by Dr. Beatriz Liliana España Sánchez from the Institute of Advanced Materials for Sustainable Manufacturing at Tecnológico de Monterrey.

[01:36:59]And we also have the second presentation entitled murine model as tools for the study of materials with biological activity. This will be led by Dr. Luis Fernando López Soto, from the Department of Medicine and Health Sciences at the University of Sonora. Well, that concludes today's events, and thank you very much, right? See you tomorrow.

[01:37:43]Government of Mexico.