Ion-pair extraction method for quantitation of a bisquaternary ammonium compound, pancuronium bromide.

Pancuronium bromide (PCBr), a neuro-muscular blocking agent, was determined quantitatively in aqueous solution by ion-pair extraction. Separate determination of PCBr and degradation products was possible after thin layer chromatography. The procedure was developed by using a theoretical approach. Favorable conditions were calculated from the ion-pair extraction constant. The drug was determined with bromothymol blue at pH 9.0, using one extraction in the direct procedure and 2 successive extractions in the combined elution-extraction process after thin layer chromatography. In the direct method, 0.100 mg PCBr was determined with a reproducibility of +/- 1.0%.