Assay for nipecotic acid in small blood samples by gas chromatography-mass spectroscopy.
An analytical method for nipecotic acid quantification in rat blood was developed utilizing a stable isotope internal standard and capillary gas chromatography-mass spectroscopy. The method involves a solid phase extraction step followed by a two-step derivatization. The analytes are separated by capillary gas chromatography and detected by selected ion monitoring of their base peaks at 180 and 185 m/z, respectively. The assay has a limit of detection (LOD) of 10 ng/ml and a limit of quantification of 26 ng/ml in 200 microl of rat whole blood. The linear range of the assay covers from 26 to 6500 ng/ml (r2=0.9996, n=9). The coefficient of variation was less than 10% at concentrations of 50, 1000 and 5000 ng/ml. The assay was used to characterize the pharmacokinetics of R-(-)-nipecotic acid in a rat. R-(-)-nipecotic acid clearance was 4.2 ml/min, its half-life was 1.5h and its volume of distribution at steady state was 325 ml.
Wang
Hongna
H
Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA.
Hussain
Anwar A
AA
Pyrek
Jan St
JS
Goodman
Jack
J
Wedlund
Peter J
PJ
D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods / Q000592:standards; D009557:Nipecotic Acids / Q000097:blood* / Q000592:standards; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D013678:Technology, Pharmaceutical / Q000379:methods* / Q000592:standards
D009557:Nipecotic Acids; C030278:nipecotic acid