Introduction
The purpose of experiment was to identify an unknown analgesic drug using thin-layer chromatography (TLC). Using the thin-layer chromatography to determine the composition of the Acetaminophen, Aspirin, Caffeine and Salicylamide, then compared with unknown analgesics.
Experiment Scheme Acetaminophen Aspirin Caffeine Salicylamide
C8H9NO C9H8O4 C8H10N C7H7NO
Figure 1. The Chemical structure of Acetaminophen, Aspirin, Caffeine and Calicylamide.
Obtain two TLC plates and 12 capillary micropipettes. Using a lead pencil lightly draw a line across the plates about 1 cm from the bottom. Then lightly mark off five same distance intervals on the line. These point use to spot samples. …show more content…
We start from left to right spot acetaminophen first, then aspirin, caffeine, salicylamide and reference. And the sample one we start from left to right: Anacin Excedrin Bufferin Tylenol and reference. It is important that the spots have to be small. Then put reference plate in a wide mouthed screwcap jar with 0.5% glacial acetic in ethyl acetate about 0.5cm depth. Wait for solvent rose to about 0.5cm from the top, take the reference plate out and using a lead pencil, mark the position of the solvent front. Then dry it, and observe it under a short-wavelength UV lamp. Mark the spot you have seen with pencil. We using a ruler to measure the distance that each spot has traveled and record on notebook. We did the same steps for the sample …show more content…
Reagents/products and respective chemical data
Solvent front
(mm) Distance (mm) Rf UV light I2
Acetaminophen 60 25 0.42 Red Yellow
Aspirin 60 38 0.63 Blue
Caffeine 60 10 0.17 Red
Salicylamide 60 42 0.70 Blue Yellow
Reference 60 10, 26, 42 0.17,0.43,0.70 Red,Red,Blue Yellow Anacin 55 9 0.16 Red Yellow
Excedrin 55 9,24 0.16,0.44 Red
Bufferin 55 36 0.65 Red
Tylenol 55 25 0.45 Red
Reference 55 9,24,41 0.16,0.44,0.75 Red Yellow
Table 2. experimental data, Solvent front, Distance, Rf.
Discussion According to Table 2, it was found that Anacin contains caffeine. This is because the Rf values for Anacin were found to be 0.16 on sample plate. We found the Rf values for caffeine was 0.17 on reference plate. So we found that Anacin contains caffeine. The Rf values for Excedrin were 0.16 and 0.44 on sample plate. Compare with reference plate, we found Excedrin contains caffeine and acetaminophen. Because of the Rf values for caffeine and acetaminophen were 0.17 and 0.42. It is similar with the Rf values of Excedrin. The Rf value for Bufferin was 0.65. I found the similar on can match with Bufferin was Aspirin (Rf=0.63). So Bufferin contains aspirin. Tylenol (Rf=0.45) contains acetaminophen
The purpose of experiment was to identify an unknown analgesic drug using thin-layer chromatography (TLC). Using the thin-layer chromatography to determine the composition of the Acetaminophen, Aspirin, Caffeine and Salicylamide, then compared with unknown analgesics.
Experiment Scheme Acetaminophen Aspirin Caffeine Salicylamide
C8H9NO C9H8O4 C8H10N C7H7NO
Figure 1. The Chemical structure of Acetaminophen, Aspirin, Caffeine and Calicylamide.
Obtain two TLC plates and 12 capillary micropipettes. Using a lead pencil lightly draw a line across the plates about 1 cm from the bottom. Then lightly mark off five same distance intervals on the line. These point use to spot samples. …show more content…
We start from left to right spot acetaminophen first, then aspirin, caffeine, salicylamide and reference. And the sample one we start from left to right: Anacin Excedrin Bufferin Tylenol and reference. It is important that the spots have to be small. Then put reference plate in a wide mouthed screwcap jar with 0.5% glacial acetic in ethyl acetate about 0.5cm depth. Wait for solvent rose to about 0.5cm from the top, take the reference plate out and using a lead pencil, mark the position of the solvent front. Then dry it, and observe it under a short-wavelength UV lamp. Mark the spot you have seen with pencil. We using a ruler to measure the distance that each spot has traveled and record on notebook. We did the same steps for the sample …show more content…
Reagents/products and respective chemical data
Solvent front
(mm) Distance (mm) Rf UV light I2
Acetaminophen 60 25 0.42 Red Yellow
Aspirin 60 38 0.63 Blue
Caffeine 60 10 0.17 Red
Salicylamide 60 42 0.70 Blue Yellow
Reference 60 10, 26, 42 0.17,0.43,0.70 Red,Red,Blue Yellow Anacin 55 9 0.16 Red Yellow
Excedrin 55 9,24 0.16,0.44 Red
Bufferin 55 36 0.65 Red
Tylenol 55 25 0.45 Red
Reference 55 9,24,41 0.16,0.44,0.75 Red Yellow
Table 2. experimental data, Solvent front, Distance, Rf.
Discussion According to Table 2, it was found that Anacin contains caffeine. This is because the Rf values for Anacin were found to be 0.16 on sample plate. We found the Rf values for caffeine was 0.17 on reference plate. So we found that Anacin contains caffeine. The Rf values for Excedrin were 0.16 and 0.44 on sample plate. Compare with reference plate, we found Excedrin contains caffeine and acetaminophen. Because of the Rf values for caffeine and acetaminophen were 0.17 and 0.42. It is similar with the Rf values of Excedrin. The Rf value for Bufferin was 0.65. I found the similar on can match with Bufferin was Aspirin (Rf=0.63). So Bufferin contains aspirin. Tylenol (Rf=0.45) contains acetaminophen