title: Development of HPLC-UV method for rapid and sensitive analysis of topically applied tetracaine: its comparison with a CZE method.
abstract: Topically applied tetracaine is a local anaesthetic. A novel HPLC method for the rapid and sensitive analysis of tetracaine was developed and compared with a short end direction capillary zone electrophoresis (CZE) method. The method was developed and validated for the separation and quantification of tetracaine in skin samples removed by 'tape-stripping'. Tetracaine was extracted from tape with 100% methanol, which was then diluted to 50% with water for injection. Tetracaine and the internal standard, procaine, were separated on a reversed-phase Luna PFP(2), 3 µm, 150 × 4.6 mm column at ambient temperature using isocratic elution with KH2 PO4 buffer (pH 2.5) and methanol (35:65, v/v). The flow rate was 1 mL/min, with detection at 312 nm. The limit of quantification for tetracaine was 0.03 µg/mL. Calibration lines were linear with r(2) values >0.99. The within- and between-assay imprecision and the percentage of inaccuracy for the QC samples including lower and upper limits of quantitation were <6 and <10%. The absolute mean recovery of tetracaine was >92%. Compared with CZE, the mean percentage error and the absolute mean percentage error were 0.62 and 6.29, respectively. The two methods were compared in a number of pharmacokinetic studies.
authors.affiliation: Clinical Pharmacology, William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London, EC1M6BQ, UK.
authors.forename: Faisal
authors.initials: F
authors.lastname: Al-Otaibi
authors.forename: Essam
authors.initials: E
authors.lastname: Ghazaly
authors.forename: Atholl
authors.initials: A
authors.lastname: Johnston
authors.forename: David
authors.initials: D
authors.lastname: Perrett
mesh_terms: D000779:Anesthetics, Local / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D019075:Electrophoresis, Capillary / Q000379:methods*; D012680:Sensitivity and Specificity; D013748:Tetracaine / Q000032:analysis*
chemical_list: D000779:Anesthetics, Local; D013748:Tetracaine
keywords: CZE; HPLC; Method comparison; Method development; Tetracaine; tape-stripping