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A differential pulse polarographic method for the analysis of colchicine-containing dosage forms is described. The reduction of the tropolone carbonyl is useful for quantitative analysis in that the relationship of the colchicine concentration to the current is linear over the concentration range of 0 to approximately 50 micrograms/ml, with a slight negative deviation at higher concentration. The procedure involves no preliminary treatment, is simple and specific, and is applicable to the assay of composite tablets, individual tablets, and injectable solutions. Polarography is conduction on a solution of colchicine in pH 1.81 Britton-Robinson buffer with 0.01% alkylphenoxy polyethoxyethanol. The quantitative analysis is achieved using the method of standard addition. A relative standard deviation of 3.2% was obtained for tablets. The results agree with those obtained using the USP XIX method.

Unambiguous 1H- and 13C-nmr assignments of colchicine, beta-lumicolchicine, and gamma-lumicolchicine have been obtained using a combination of 1D- and 2D-nmr spectroscopic techniques. The data indicate that gamma-lumicolchicine is a stereoisomer of beta-lumicolchicine and provide definitive evidence for their stereochemical assignments.