title: LC-APCI mass spectrometric method development and validation for the determination of atovaquone in human plasma.
abstract: A newly developed LC-APCI mass spectrometric method is described for human plasma determination of atovaquone using lapachol internal standard. A single-step protein precipitation technique for plasma extraction of atovaquone achieving mean recovery of 94.17% (CV 8%) without compromising sensitivity (limit of quantitation 50.3 ng/mL) or linearity (50.3 ng/mL-23924.6 ng/mL) is delineated in this paper. Heated nebulizer in negative multiple reaction monitoring mode was employed with transitions m/z 365.2 --> m/z 337.1 and m/z 240.9 --> m/z 185.7 for atovaquone and lapachol respectively in this liquid chromatographic-tandem mass spectrometric method. Excellent chromatographic separation on a Synergi 4 micro Polar-RP 80A (150 x 2.0 mm) column, using 100 microL of plasma extraction volume along with 10 microL of injection load, completing analysis run-time within 2.5 min, highlights this simple yet unique bioanalytical method. The developed method can be successfully applied to pharmacokinetic studies on atovaquone suspension administered in healthy volunteers or HIV-infected patients. Moreover full method validation results not published before are presented and discussed in detail for the first time in this article.
authors.affiliation: Department of Clinical Pharmacology and Pharmacokinetics, Ranbaxy Laboratories Ltd, Gurgaon, Haryana, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Gurule
authors.forename: Dipanjan
authors.initials: D
authors.lastname: Goswami
authors.forename: Arshad H
authors.initials: AH
authors.lastname: Khuroo
authors.forename: Tausif
authors.initials: T
authors.lastname: Monif
mesh_terms: D000890:Anti-Infective Agents / Q000097:blood*; D053626:Atovaquone / Q000097:blood*; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D009285:Naphthoquinones; D012015:Reference Standards; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000890:Anti-Infective Agents; D009285:Naphthoquinones; C008252:lapachol; D053626:Atovaquone