Yiming Zhang September 13, 2017 TLC Analysis of Analgesic Drugs Introduction The purpose of this experiment was to determine the composition of the four counter analgesics on the counter by a method which called thin-layer chromatography (TLC). According to the appearing of the distance they have traveled we can identify if the unknown mixture contained acetaminophen, aspirin, caffeine or salicylamide. Experimental scheme Acetaminophen(Ac) Aspirin(Asp) Caffeine(Cf) Salicylamide(Sal) First, prepared enough micropipets for furture use to spot on TLC plates. Four unknown analgesics and one reference mixture(mixture of acetaminophen, aspirin, caffeine or salicylamide.) would be spotted on two TLC plates. …show more content…
The principle of the differences of the distance showed are due to the solvibility of different analgestic. Some analgesic are having the similar distance appeared on the TLC plates, under this circumstances, we can identify them by put them into iodine jar for further observing. We can compare and analysis the data from the Table 2 and 3 to indentify what are exactly in the unknown mixture.Also, there were some fault I made during this experiment, which if I do this experiment again I will avoid. For example I had spotted the analgesic spot too large, which would lead a difficulty to observe and analysis. Of course, we can’t make the spots even too small, if we need, we are not willing to observe. I think it is an interesting experiment, I have done same one before when I was in China, but we didn’t have the short wavelengh UV lamp due to the limited condition. This time I worked with my American teammates and have gained a lot. Question 1. The spots will tail and overlap one and another after developed. Hard for us to observe and distinguish. 2. The ink of the ballpoint pen will be disolved in the solvent which would interfere experimental