The recovery of alkaloids after their location on thin layer chromatograms

A method was developed for the recovery of 29 alkaloids from TLC plates after they had been complexed with either potassium iodoplatinate (for tertiary amines) or carbon disulphide (for primary and secondary amines). A comparison was made between the percentage recoveries of these alkaloids from 5 different types of TLC plate. In addition, the stability of these alkaloids on TLC plates over a 7 day period was studied. Assays were, where possible, carried out by UV spectrophotometry but gas chromatography was used for alkaloids which possessed low UV absorbtivity values. All the alkaloids extracted from TLC plates were examined by low resolution mass spectrometry.