Chromatography Methods Sample Clauses

Chromatography Methods. Generally, TLC, LC and other chromatographic methods are extremely effective separation methods, but they can be long and tedious. Furthermore, it is limited to small scale work involving less than 1 g unless appropriate facilities are available. The above methods should only serve as a guide. Usually, methods (b) and (c) would be suitable. Also note that many problems could arise in the process of recovering the separated components (refer text). In principle, all the given amounts should be recoverable unless they are accidently thrown away or are extremely volatile. It may be wise to try a small-scale separation to assess on your separation method before scaling up. Compounds that are separated and purified should have good physical constants, e.g., m.p., b.p., etc., before it is sent for spectra analysis. Proceed to determine the elements present, run both NMR and IR spectra and do some wet tests to determine the functional type. Make at least one good derivative. If no derivative is possible, do a chemical transformation to give a product that can be easily characterised by NMR. Comparison of Rf values or retention times with standards under different conditions is also acceptable.