title: A highly sensitive LC-MS/MS method for the determination of S-raclopride in rat plasma: application to a pharmacokinetic study in rats.
abstract: A highly sensitive and rapid assay method has been developed and validated for the estimation of S-(-)-raclopride (S-RCP) in rat plasma with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive ion mode. The assay procedure involves a simple liquid-liquid extraction technique for extraction of S-RCP and phenacetin (internal standard, IS) from rat plasma. Chromatographic separation was achieved with 0.2% formic acid : acetonitrile (80:20, v/v) at a flow rate of 0.30 mL/min on a Phenomenex Prodigy C(18) column with a total run time of 4.5 min. The MS/MS ion transitions monitored were 347.2 → 112.1 for S-RCP and 180.1 → 110.1 for IS. Method validation and pre-clinical sample analysis were performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.05 ng/mL and the linearity range was extended from 0.05 to 152 ng/mL in rat plasma. The intra-day and inter-day precisions were 0.23-10.5 and 3.74-7.29%, respectively. This novel method was applied to a pharmacokinetic study of S-RCP in rats.
authors.affiliation: Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, 2nd Stage, Industrial Suburb, Yeshwanthpur, Bangalore-560 022, India.
authors.forename: P S
authors.initials: PS
authors.lastname: Suresh
authors.forename: Ravindra Ramachandra
authors.initials: RR
authors.lastname: Punde
authors.forename: Manish
authors.initials: M
authors.lastname: Gupta
authors.forename: Abhishek
authors.initials: A
authors.lastname: Dixit
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Giri
authors.forename: Sriram
authors.initials: S
authors.lastname: Rajagopal
authors.forename: Ramesh
authors.initials: R
authors.lastname: Mullangi
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D016014:Linear Models; D008297:Male; D020891:Raclopride / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D020891:Raclopride