Quantitative extraction of tubocurarine, gallamine, and decamethonium from biological materials

A procedure is described for quantitative extraction of tubocurarine, gallamine, and decamethonium from blood, urine, and tissue. Ion pairs of the drugs are formed with picric acid and are extracted into a dichloromethane/1-pentanol solvent. Qualitative analysis of the extract is effected using thin-layer chromatography. Quantitative analysis is accomplished by elution of TLC areas containing the drug, formation of the ion pair with sodium 9,10-dimethoxyanthracene-2-sulfonate, and analysis of the ion pair by spectrophotofluorometry.