title: Determination of efavirenz in human plasma by high-performance liquid chromatography with ultraviolet detection.
abstract: Efavirenz is a non-nucleoside reverse transcriptase inhibitor for the treatment of the HIV infection. A simple, high-performance liquid chromatographic method has been developed and validated for the quantitative determination of efavirenz in human plasma. The method involved solid-phase extraction of the drug and the internal standard (L-737,354) from 300 microl of human plasma. The analysis was via UV detection at 250 nm using a reversed-phase C8 analytical column and a isocratic mobile phase consisting of phosphate buffer (pH 5.75)-acetonitrile that resolved the drug and internal standard from endogenous matrix components and potential coadministered drugs. Within- and between-day precisions were less than 8.6% for all quality control samples. The lower limit of quantification was 0.1 microg/ml. Recovery of efavirenz from human plasma was greater than 83%. This validated assay is being used in pharmacokinetic studies with efavirenz.
authors.affiliation: Clinical Pharmacology Service (UASP, Unitat d'Avaluació, Suport i Prevenció), Hospital Clinic, Barcelona, Spain. msarasa@clinic.ub.es
authors.forename: M
authors.initials: M
authors.lastname: Saras-Nacenta
authors.forename: Y
authors.initials: Y
authors.lastname: López-Púa
authors.forename: L F
authors.initials: LF
authors.lastname: Lípez-Cortés
authors.forename: J
authors.initials: J
authors.lastname: Mallolas
authors.forename: J M
authors.initials: JM
authors.lastname: Gatell
authors.forename: X
authors.initials: X
authors.lastname: Carné
mesh_terms: D000480:Alkynes; D048588:Benzoxazines; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003521:Cyclopropanes; D006801:Humans; D010078:Oxazines / Q000097:blood* / Q000493:pharmacokinetics; D012015:Reference Standards; D015203:Reproducibility of Results; D018894:Reverse Transcriptase Inhibitors / Q000097:blood* / Q000493:pharmacokinetics; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000480:Alkynes; D048588:Benzoxazines; D003521:Cyclopropanes; D010078:Oxazines; D018894:Reverse Transcriptase Inhibitors; C098320:efavirenz