Chromatography in Forensic Science : Identification of Drugs, Poisons and Alcohol in Blood and Urine

[00:00:04]Get Hello everyone. Today our will be presenting on chromatography in therapeutic science identification of drugs, poisons and alcohol in blood and my name is and I will begin by introducing the benefit of chromatography explaining its application in photography is an analytical technique used to separate identify and analyze the components of a question. It works by separating substances that interact with different places because different substances they can be separated and identified individually. The principle of chromatography is based on the different instruction of substances to two places the stationary base and the mobile base.

[00:01:13]Companies that are more strongly attached to the stationary pace move more slowly while components that they that are more attracted to the mobile pace move fast. This difference in movement allows the mixture to separates into two components. Stationary face is the part that speaks things such as silicia or paper. It interacts with the sample components. Mobile paste is a liquid or gas that must strengthen precision phase and generate the sample alone. Together these two phase separation process visible.

[00:01:47]Chromatography is important because it provides accurate and reliable identification of substances and complex mixtures. It is what used in many ways including food safety, environmental testing and science.

[00:02:04]In our presentation, we will focus on its application in forensic science.

[00:02:08]Chromatography is used to analyze blood and human samples to identify drugs, poisons and alcohol. This information helps forensic science investigating cases involving drug abuse, poisoning, impaired driving, unexplained death.

[00:02:24]That introduction, I will now hand over to the next presenter who will explain how therapy is used in exercise. Today I will present the application of chromatography in forensic science especially its role in identifying drugs, poisons and alcohol in blood and urine samples. For the background of the application, chromatography is an example technique used in forensic toxicology. It helps investigator to detect and analyze substance such as drugs, poisons and alcohol in biological samples. This techniques is useful in cases involving drug abuse, poisoning, overdose and drunk driving accidents. It works by separating complex mixture into individual compounds making identification easier and more accurate.

[00:03:06]Why chromatography is used?

[00:03:08]Chromatography is widely used because it has several advantages. First, it is highly sensitive meaning it can detect even very small amounts of substance.

[00:03:16]Second, it is highly selective and can separate compounds with similar structures. Third, it provides accurate identification through retention times and other analytical data. Lastly, it can measure the concentration of substance in complex samples like blood and urine. Because of these advantages, chromatography is one of the most reliable methods in forensics investigations.

[00:03:38]These are the types of chromatography that been used in forensic toxicology.

[00:03:44]The first type is case chromatography or GC. It is mainly used for volatile compounds which are substance that easily evaporate such as alcohol and certain solvents. The second type is high performance liquid chromatography or we call it as HLC. It is used for nonvolatile and heat sensitive compounds. This method is commonly applied in detecting prescription drugs, illegal drugs, poisons and drug metabolities. And the third one we have thin layer chromatography or TLC. It is a simple and inexpective screening technique. LC is mainly used for preliminary drug testing and poison screening before more advanced analysis are performed. You must be wondering the theory of how separation occurs. The principles of chromatography is based on the interaction between two phases. the stationary phase and the mobile phase.

[00:04:29]Compounds that are more strongly attracted to the stationary phase move more slowly while compounds that are more attracted to mobile phase move faster. Because different substance move at different speeds, they become separated and can be identified individually. For examples, in GC separation depends mainly on volatility.

[00:04:45]In HLC and TLC, separation is large based on polarity. All right, let's talk about methodology. When a forensic scientist gets a raw blood or urine sample, we can't just inject it straight into our instruments. The proteins and fats will instantly ruin the system. So, step one is a chemical cleanup called solid phase extraction SP which you can see on the slide. We pour the messy sample into a specialized criridge. This cartridge act like a chemical magnet trapping our hidden suspects the drugs or poisons while letting all the biological waste wash right out. A final rinse releases our now crystal clear concentrated sample. Now that it's clean, we have to separate the chemical crowd. Depending on the culprit, we take one of two analytical highways. For volatile targets like alcohol, we use gas chromatography. For heavy heat sensitive toxins or elicit drugs, we use high performance liquid chromatography which is HLC. As the diagram shows, a mobile phase forces our sample through a tightly packed column because different chemicals travels at different speeds based on their structure. They spread out by the end of the line. A chaotic mixture is perfectly separated into pure individual compound. So what does the final data look like? When those separated chemicals cross the finish line, they hit a detector creating a graph called chromatoggram. We read this using two main clues. First, retention time, how long the chemical took to pass through the column. Since every drug has a signature speed, this identifies what it is. Second, peak area. The bigger the spike on the graph, the higher the concentration of the poison in the system. Pairing this with a mass spectrometer give us an undeniable chemical fingerprint. The ultimate gotcha moment in a forensic lab.

[00:06:50]So now we move on to the advantages of chromatography in forensic sciences.

[00:06:54]First of all, chromatography has high sensitivity in which chromatography can detect very small amounts of drugs, poisons or alcohol in blood and urine.

[00:07:05]And then it has high accuracy and reliability in which it produces reliable results that can be used as scientific evidence in court. And it also separates complex biological samples because blood and urine contains many compounds and chromatography separates the target substances from other components. Chromatography can also identify multiple substances simultaneously in which a single analysis can detect different drugs, poisons and alcohol metabolites. Last but not least, chromatography is a widely accepted method in forensic laboratories in which techniques such as GCMS, gas chromatography, mass spectrometry and LCMS, liquid chromatography and the mass spectrometry are considered to gold standard in forensic toxicology.

[00:07:50]Now we move on to the limitations of chromatography in forensic science.

[00:07:54]First of all, chromatography requires expensive equipment in which advanced instruments like GCMS and LCMS are costly. It also requires trained personnel in which skill analysis are needed to operate the instruments and interpret the results. Chromatography in forensic science also requires timeconuming sample preparation in which blood and urine often require expression and purification before analysis. Also, not every substance can be analyzed by one method. Some compounds require gas chromatography while others require liquid chromatography.

[00:08:26]Last but not least, the results depend on proper sampling collection and storage.

[00:08:31]in which for handling may affect the accuracy of the analysis.

[00:08:36]In conclusion, chromatography is a powerful analytical technique used to separate, identify and analyze the components of complex mixtures. In forensic science, it plays a vital role in detecting drugs, poisons, and alcohol in biological samples such as blood and urine. Its high accuracy, sensitivity, and reliability makes it an essential tool for forensic investigations, toxicology, and legal proceedings.

[00:08:59]Although advanced chromatographic techniques require specialized equipment and trained personnel, they remain one of the most trusted methods for providing scientific evidence and ensuring accurate forensic analysis.