Determination of a novel indolylpiperazine anti-migraine agent in rat, monkey, mouse and rabbit plasma by high-performance liquid chromatography with electrochemical detection.
A specific, accurate, precise and reproducible assay for the quantitation of a novel indolylpiperazine anti-migraine agent (I) in plasma from various animal species is described. The method involves addition of internal standard (I.S.) and 1.0 M sodium carbonate to the plasma sample, vortex-mixing and extraction with ethylene dichloride. The organic layer is then back-extracted in a buffer consisting of 0.1 M tetramethylammonium hydroxide (TMAH), pH 3.0 and 0.1 M (NH4)2HPO4, pH 3.0, in water. The aqueous layer is injected on to a Zorbax cyano analytical column with a mobile phase consisting of acetonitrile, methanol and water (15:5:80, v/v/v) with 0.01 M TMAH, pH 3.0 and 0.01 M (NH4)2HPO4, pH 3.0. The eluate is monitored by electrochemical detection at 0.9 V (guard cell), 0.5 V (detector 1) and 0.8 V (detector 2). The retention times of I and I.S. were 7 and 10 min, respectively. In drug-free control plasma, there were no interfering peaks seen at the retention times of I or I.S. The standard curve was linear over the concentration range of 5-500 ng/ml in rat, monkey, mouse and rabbit plasma. The lower limit of quantitation in all four matrices was 5.0 ng/ml. Within- and between-assay variability of quality control samples was less than 9% relative standard deviation and the predicted concentration of the quality control samples deviated by less than 15% from the nominal concentration. The stability of I was established for up to 36 h in the autosampler tray, up to 10 months in plasma at -20 degrees C and up to 2 h in plasma at room temperature. The assay is validated for determination of I in plasma.
Marathe
P H
PH
Department of Metabolism and Pharmacokinetics, Bristol-Myers Squibb Company, Princeton, NJ 08543, USA.
Larkin
K D
KD
Duncan
G F
GF
Greene
D S
DS
Barbhaiya
R H
RH
D000818:Animals; D002021:Buffers; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D004355:Drug Stability; D004563:Electrochemistry; D000882:Haplorhini; D006863:Hydrogen-Ion Concentration; D007211:Indoles / Q000097:blood* / Q000493:pharmacokinetics; D007700:Kinetics; D051379:Mice; D008881:Migraine Disorders / Q000188:drug therapy*; D000644:Quaternary Ammonium Compounds; D011817:Rabbits; D051381:Rats; D012680:Sensitivity and Specificity; D013449:Sulfonamides / Q000097:blood* / Q000493:pharmacokinetics; D014363:Tryptamines
D002021:Buffers; D007211:Indoles; D000644:Quaternary Ammonium Compounds; D013449:Sulfonamides; D014363:Tryptamines; C103231:avitriptan; C027917:tetramethylammonium