TLC Analysis of Analgesic Drugs
This experiment is somewhat different
from what is described in your book. We will only
determine whether two unknowns contain Aspirin, Acetaminophen, and/or Caffeine.
The exact procedure will be given in lab. For your information I have included
a brief outline here.
Modified Procedure:
- Using two plates- developed in ethyl acetate
- First plate - Standard Solutions
- Solution 1: Acetaminophen in a 50:50 mixture of
ethanol-methylene chloride
- Solution 2: Aspirin in a 50:50 mixture of
ethanol-methylene chloride
- Solution 3: Caffeine in a 50:50 mixture of
ethanol-methylene chloride
- Second Plate
- Unknown A
- Standard Reference mixtures of Solutions 1, 2, and 3.
- Unknown B
- Calculate the Rf values of each analgesic, then compare the Rf values
of each of the constituents of the unknown to the standards. Identify the
commercial product using the table on page 56.
- Rf = (Distance traveled by the spot) / (distance traveled by the solvent)
- The Rf value of each chemical is characteristic for the solvent system
used.
Additional Information:
Thin Layer Chromatography Video: http://yip5.chem.wfu.edu/yip/Video/TLC.MOV
(1804K)
A Description of Chromatography: http://www.silcom.com/~toad/chromo/chroma.htm
