title: Determination of oxyphenonium bromide in plasma and urine by means of ion-pair extraction, derivatization and gas chromatography-electron-capture detection.
abstract: A sensitive and selective method for the determination of the quaternary ammonium compound oxyphenonium bromide (Antrenyl), a drug with strong anticholinergic properties, in human plasma and urine is described. The method is based on ion-pair extraction of the cation with perchlorate, a re-extraction according to ion-pair principles with tetrapentylammonium as the counter ion, hydrolysis to cyclohexylphenylglycolic acid, derivatization of this acid to its pentafluorobenzyl ester and determination of the ester by gas chromatography and electron-capture detection. Quantitation is possible down to 2 ng/ml of oxyphenonium bromide using 1 ml of plasma and down to 200 ng/ml using 0.1 ml of urine. The method described can also be applied to other anticholinergic drugs with an ester function.
mesh_terms: D000818:Animals; D002849:Chromatography, Gas / Q000379:methods; D002852:Chromatography, Ion Exchange; D006801:Humans; D010115:Oxyphenonium / Q000032:analysis* / Q000097:blood / Q000652:urine; D000644:Quaternary Ammonium Compounds / Q000032:analysis*
chemical_list: D000644:Quaternary Ammonium Compounds; D010115:Oxyphenonium