CHM256 APPLICATION OF THIN LAYER CHROMATOGRAPHY

[00:00:00]group will present on the topic of the application of thin layer chromatography or TLC. So without further ado, let's get started.

[00:00:09]So what is chromatography? Well, chromatography is a separation technique used to separate compounds of the mixture based on the different rates at which they move through the stationary phase and the mobile phase. In thin layer chromatography or TLC, there is a thin layer of silica gel or aluminina that is coated on a glass plastic or an aluminum plate. The mobile phase is a suitable solvent that moves up the plate through the capillary action.

[00:00:37]So TLC is widely used because it is simple, fast, low cost and requires only a small amount of samples. It is used in pharmaceutical analysis, food testing and forensic science. It is used for preliminary screening before more advanced techniques such as HLC. It also helps chemists to quickly determine whether a mixture contains one or more compounds. Not only that, it is also widely used in teaching laboratories as an experimental technique.

[00:01:07]So the theory of TLC is that it is given by the formula RF which equals to the distance traveled by the compound divided by the distance traveled by the sol. The core principle of TLC is that compounds with stronger interactions with the stationary phase will take longer time to move and compounds with weaker interactions will move further and therefore faster. So the solvent is used to determine the separation of the compound. So selecting the correct solvent is important to achieve a good separation. So the movement of each compound is represented by the RF or retention factor. It ranges from 0 to one and that also means that some compounds may have similar RF values. So comparison with standards are actually necessary.

[00:01:52]Next part is methodology. Stepby-step practical process. First dry a pre-cut TLC plate to remove moisture. This help the compound stick to its better. The secondly is use a tiny tube to put a small concentrate dot of your mixture near this bottoms of the plate. So more place the plate upright in a covered chamber filled with a small amount of liquid solvent. Make sure liquid level is a below your sample dot so it doesn't wash away. Furthermore, the liquid will clean up the plate naturally as it rise.

[00:02:33]it carries the mixture with it and separating it into different spots. So last but not least, take the plate out and immediately mark how hide the liquid cream. So if the spots are invisible, look at them under UV light or spray them with specific chemical to make them show up. Lastly, make sure the distance the solvent travel and the distance each spot travel. divide the spot distance by the solvent distance to get the RF value which help identify the compound you can see here. So this example of the result where TLC analysis is the separation of plant distance traveled by solvent 8.9 where pigment A travels 6.4 we put our data into the formula RF 6.4 over 8.9 = to 0.8 8 for pigment B travel 4.6 4. CMS RF 4.3 over 8.9 equal to 0.5.

[00:03:38]So comparison of this RF value with the reference value helps in the identification of the compounds.

[00:03:44]However, it is important to note that RF values alone are not always sufficient for identification. So as they might change depending on experimental condition such as solvent type, temperature and flat material.

[00:03:59]>> Moving on to application of thin layer chromatography which is TLC. So TLC or stand for thin layer chromatography is a simple fast and low cost method used to separate identify and monitor different substant in mixture.

[00:04:17]One of its most important uses is in food analyst. TLC help detect food addictive, preservative, coloring and contaminants to make sure food is safe to eat. It also used to analyze food components such as vitamin, sugar and fat. Because of this, TLC is widely used in food quality control. The researcher wanted us to understand that food content mixture of compounds.

[00:04:45]Chromatography can separate this compound chemical has practical application in everyday life. We divide our material into four groups. The first one is beverage leaf and fruit vegetable and citrus. Most of the material is extracted using enamel. Tomatoes and carrots were extracted using ethil acetate because they are contain non-polar compound that do not dissolve well in internal.

[00:05:12]Now let's look at our first result. Uh different food produce different pattern. This is because each food has different chemical composition.

[00:05:22]So on the left is group two which is includes spinach, tree leaves and blueberries.

[00:05:29]Spinach and tree leaves produce many colorful spot on the TLC plate. This show that contains several different pigment and chemical compounds.

[00:05:40]On the right is group three which include carrot and tomatoes. This sample produce a bright orange spot near the solvent fronts. This indicate the present of non-polar pigment called carotenoid such as beta caroten and lycopen. So overalls this result show that SLC can separate and identify different plant pigment based on their chemical properties.

[00:06:04]>> Next is result two which is blue spot after CM standing. After treatment with CM stand compound appear as blue spot.

[00:06:13]Different food samples show different numbers and positions of spot. This confirm that each food extract content at different mixtures of chemical. As you can see the A1 we have beverage we use coffee and green tea and the B1 uh which is the leaf and fruit we use pineatch leaf blueberries and the C1 we have vegetable we use red cabbage tomato and carrots and the D1 we use uh ch peels we have lemon peels, lime peels and also orange peels. Next is result three which is mix and match experiment.

[00:06:53]Extract from different group and analyze them together. Sample that we use is orange peels, spinach, carrots and also coffee. The core spot lens show all spot from the individual sample confirming that TLC successfully separated compounds from multiple food sources.

[00:07:15]Why do different food produce different spot? It is because it contains different chemical compounds. For example, tea is contain poly panels and caffeine. Spinach contain chlorophyll.

[00:07:27]Tomato contains lycopine.

[00:07:30]Carrots contain B carotene. Uh chills contain essential oil. And so it become like different me polarities. They travel different distance of the TLC plates producing the separate. Why were tomato and carrot spot near the solvent front? It is because the solvent system contain a relative non-polar component contain non-polar keratenoid pigment dissolve well in the mobile paste and travel further up the plate. This is why an orange pot appear near the solvent front. Our TLC analysis was successful by separating the compound in food extracts. Each sample show its own unique pattern. We use a ceric ammanium molidate cam stand to make the invisible compound appear as blue spot on the TLC plate. The cospot experiment also shown that TLC can separate compound from different sample on the same plate.

[00:08:36]Overall, this proved that the TLC is a simple, fast and effective method for separating and identifying compound. In conclusion, thin layer chromatography TLC is a simple, fast and useful method for separating and identifying compound.

[00:08:54]It work by using the different interaction of substance with the stationary and mobile faces. From the food extract case study, we saw how different pigment were separated and identified. Overall, TLC is an important technique that is widely used in food analysis, quality control and many other laboratory application. So that's all from our group. Thank you.