Separation of eight alkaloids and meconic acid and quantitation of five principal alkaloids in gum opium by gradient reversed-phase high-performance liquid chromatography.

The separation of the five principal alkaloids (morphine, codeine, thebaine, noscapine and papaverine), three minor alkaloids (laudanosine, cryptopine and narceine), meconic acid and some unidentified constituents in gum opium samples has been achieved on a reversed-phase phenyl column by gradient high-performance liquid chromatography using a simple and inexpensive mobile phase system. The linear gradient programme was started at 5% and ended at 70% methanol in triethylammonium phosphate buffer in 20 min. The five principal alkaloids were also determined with good precision. The method requires minimum sample preparation and is suitable for routine analysis.

Spectrophotometric determination of 2-amino-3H-phenoxazin-3-one as a colouring matter in o-aminophenol.

A spectrophotometric method using 0.5M hydrochloric acid in methanol as solvent, has been used for the determination of 2-amino-3H-phenoxazin-3-one [APZ], occurring as a coloured impurity in o-aminophenol [OAP]. This impurity dissolves in the acid medium, giving a stable red solution which complies with Beer's law. The method can be applied to the determination of APZ in technical samples of OAP.