title: High-performance liquid chromatography of the antihistamine pyrilamine and its N-oxide using electrochemical detection.
abstract: The electrochemical behavior of the over-the-counter antihistamine drug pyrilamine and its N-oxide analogue, have been studied by several voltammetric methods. Cyclic voltammograms of pyrilamine maleate in 0.1 M ammonium acetate at pH 7.0 indicated a quasi-reversible electrode process by observing a wave at + 0.85 V and + 1.30 V in the initial anodic sweep followed by a wave at - 1.30 V versus Ag/AgCl. Differential pulse and hydrodynamic voltammetry of pyrilamine and the N-oxide were examined to determine oxidation potentials for use in high-performance liquid chromatography with electrochemical detection (HPLC-ED). Differentiation between pyrilamine and its N-oxide was achieved in HPLC-ED analyses at a detection potential of + 0.7 V and + 0.9 V versus Ag/AgCl with tandem ultraviolet detection at 254 nm. Utility of the HPLC-ED method was demonstrated by the analysis of pyrilamine and the N-oxide in microbial biotransformation samples.
authors.affiliation: Food and Drug Administration, National Center for Toxicological Research, Jefferson, AR 72079.
authors.forename: S M
authors.initials: SM
authors.lastname: Billedeau
authors.forename: C L
authors.initials: CL
authors.lastname: Holder
authors.forename: T A
authors.initials: TA
authors.lastname: Getek
mesh_terms: D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003497:Cyclic N-Oxides / Q000032:analysis*; D004563:Electrochemistry / Q000379:methods; D009090:Mucorales / Q000378:metabolism; D011738:Pyrilamine / Q000031:analogs & derivatives* / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D003497:Cyclic N-Oxides; C049169:pyrilamine N-oxide; D011738:Pyrilamine