Thin Layer Chromatography
Title: Thin Layer Chromatography
Chemical analysis is conducted on specific analytes (specific substance of interest in a mixture), however it is often found that these analytes must be separated for the chemical analysis to conduct their analysis.
Chromatography is a set up of laboratory a technique that is used to separate a chemical mixture. This technique is very useful as it allows us to follow the course of the reaction and separation of the product from the mixture. There are preparative and analytical Chromatography conducted, function of a preparative Chromatography is to separate the mixture for further usage allowing purification. Analytical Chromatography is done to evaluate the concentration of analyte is the small amount of solute.
The main component of the Chromatography consist of the mobile phase and also stationary phase. We can describe the mobile phase as the phase that moves through the stationary phase. The mobile phase can be a liquid, gas or a supercritical fluid.The mobile phase carries along the analyte that is needed to be separated or analyzed through a stationary phase which has different degree where the mixtures are absorbed at various rate.
The aim for part 1 of the Thin Layer Chromatography is to learn the technique and visualization of the colorless compound. Secondly, is to identify the unknown compound based on the comparisons made with standard compound.
The aim of separation technique by Thin Layer Chromatography is to separate the mixture of individual compounds from the spinach leaf sample used. Material and apparatus:
Part 1 : Analysis of Analgesic Drugs
Measuring cylinder 10 & 5 ml
The standard sample consisting of Aspirin ,Acetaminophen ,Caffeine ,Unknown A and Unknown B was prepared. Firstly, TLC plate were spotted where a 5cm x 10 cm plate was used. The TLC place was set down with the silica gel coating facing upward on a clean dray surface. Secondly use a blunt 2B pencil to make a line horizontally that is 1 cm away from the bottom edge. A second line was drawn 5 cm from the top edge horizontally. On the bottom line make 5 dots where the first dot is 0.9 cm from the left edge and consequent dots that are 0.8 cm away from each other. 5 analgesics were spotted with the arrangement starting from Acetaminophen ,Caffeine ,Unknown A ,Aspirin and Unknown B. 5 to 7 spots were made and the concentration was examined under the Ultra violet light. The developing chamber was than prepared using a 250 ml beaker were 10 ml of ethyl acetate and 5 ml of hexane are measure and poured. 5 drops of acetic acid was than added to the mixture, the TLC plate is than placed in and sealed with aluminium foil. The TLC plate was removed when the solvent reached the top horizontal line and view under Ultra violet light with 250 nm and 350 nm wavelengths. The visible spots were recorded and placed in the Iodine vapor chamber. The Brown spots visible are than recorded.
Part 2: Thin Layer Chromatography for components of spinach. Material:
9.5 cm3 CH2Cl2
0.5 cm3 CH3OH
10 cm Acetone
4 cm petroleum spirit
2.5 cm x 10 cm TLC Plate
Measuring cylinder 10 & 5 ml
Pastel and mortar
10 cm vial
Firstly, TLC plate was prepared using a 2.5cm x 10 cm plate. The TLC place was set down with the silica gel coating facing upward on a clean dray surface. Secondly use a blunt 2B pencil to make a line horizontally that is 1 cm...
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