Chrom

Thin Layer Chromatography

Aim: To understand, develop and correctly set up the concept of how Thin Layer Chromatography works and use it to separate two drugs of different polarity.

Introduction: This is an introduction to chromatography, using the thin layer chromatography as an example. Thin Layer is an analytical technique to determine the composition of a mixture. This analytical technique is one of the many processes that are used in forensic science. The thin Layer chromatography is a method which can be used on a wide variety of materials and it’s based on silica gel as stationary phase and the mixture of solvents as mobile phase. TLC is an analytical tool widely used because of its simplicity. It’s performed on the analytical scale, meaning the monitoring of the progress of reaction or on the preparative scale to purify small amount of compounds. .A chromatography is used to separate mixtures of substances into their own components. Usually the mobile phase flows through the stationary phase and then carries the components. Different components travel at different rates. The 3 mixtures that were used in the experiment were cocaine, methanol and benzyl. Cocaine is an alkaloid. The chemical name for cocaine is benzoylmethyl-ecogine. The cocaine chemical structure consists three parts: lipophilic group, hydrophilic group and an aliphatic group (Sabino, 2011). Benzoylecogonine is a topical analgesic and it’s the main metabolite of cocaine. It’s the corresponding or carboxylic acid of cocaine and it’s a methyl ester (Evans, 1979). Methanol is an alcohol compound, which contains three hydrogen atoms and one carbon atoms which makes the methyl group (CH3).

Method: First of the TLC tank was prepared with the mobile phase (MeOH/ conc. NH3, 100/1.5 by volume). Then the UV active chromatographic plate was marked by a pencil so it could show the Methanol solution, Cocaine solution and the Benzoylecogonine solution. Each of Methanol, Cocaine solution and the...