Determination of phenazopyridine in human plasma by GC-MS and its pharmacokinetics.
A sensitive, selective, and simple gas chromatography-mass spectrometry method is developed for quantitation of phenazopyridine (PAP) in human plasma using internal standard (diazepam). PAP and IS are extracted from plasma by liquid-liquid extraction and analyzed on a DB-5MS column with mass selective detector. Excellent linearity is found between 5-500 ng/mL (r = 0.9992, n = 7) for PAP in human plasma. The limit of detection is 0.3 ng/mL. Intra- and Inter-day precisions expressed as the relative standard deviation for the method are 1.37-6.69% and 1.24-6.01%, respectively. Extraction efficiency is more than 90%, and recoveries are in the range of 92.65-96.21%. This method is successfully applied for the pharmacokinetics and bioequivalence of 2 formulations of PAP in 18 healthy male volunteers who received a single 200 mg dose of each formulation.
Li
Kai-jun
KJ
Department of Pharmacy, Affiliated Dongfeng General Hospital, Yunyang Medical College, Hubei 442008 PR China.
Chen
Qin-hua
QH
Zhang
Zhuo
Z
Zhou
Peng
P
Li
Peng
P
Liu
Jia
J
Zhu
Jun
J
D000700:Analgesics / Q000097:blood* / Q000493:pharmacokinetics; D001682:Biological Availability; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D010621:Phenazopyridine / Q000097:blood* / Q000493:pharmacokinetics; D012015:Reference Standards; D013810:Therapeutic Equivalency
D000700:Analgesics; D010621:Phenazopyridine