title: Development and validation of an automated solid phase extraction and liquid chromatographic method for the determination of piperaquine in urine.
abstract: A sensitive and specific bioanalytical method for determination of piperaquine in urine by automated solid-phase extraction (SPE) and liquid chromatography (LC) has been developed and validated. Buffered urine samples (containing internal standard) were loaded onto mixed phase (cation-exchange and octylsilica) SPE columns using an ASPEC XL SPE robot. Chromatographic separation was achieved on a Chromolith Performance RP-18e (100 mm x 4.6 mm I.D.) LC column with phosphate buffer (pH 2.5; 0.1 mol/L)-acetonitrile (92:8, v/v). Piperaquine was analysed at a flow rate of 3 mL/min with UV detection at 347 nm. A linear regression model on log-log transformed data was used for quantification. Within-day precision for piperaquine was 1.3% at 5000 ng/mL and 6.6% at 50 ng/mL. Between-day precision for piperaquine was 3.7% at 5000 ng/mL and 7.2% at 50 ng/mL. Total-assay precision for piperaquine over 4 days using five replicates each day (n = 20) was 4.0%, 5.2% and 9.8% at 5000, 500 and 50 ng/mL, respectively. The lower limit of quantification (LLOQ) was set to 3 ng/mL using 1 mL of urine, which could be lowered to 0.33 ng/mL when using 9 mL of urine and an increased injection volume.
authors.affiliation: Department of Pharmacology, Sahlgrenska Academy, Göteborg, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Tarning
authors.forename: T
authors.initials: T
authors.lastname: Singtoroj
authors.forename: A
authors.initials: A
authors.lastname: Annerberg
authors.forename: M
authors.initials: M
authors.lastname: Ashton
authors.forename: Y
authors.initials: Y
authors.lastname: Bergqvist
authors.forename: N J
authors.initials: NJ
authors.lastname: White
authors.forename: N P J
authors.initials: NP
authors.lastname: Day
authors.forename: N
authors.initials: N
authors.lastname: Lindegardh
mesh_terms: D000818:Animals; D002626:Chemistry, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D011786:Quality Control; D011804:Quinolines / Q000652:urine*; D012044:Regression Analysis; D015203:Reproducibility of Results; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D013997:Time Factors; D014466:Ultraviolet Rays; D016482:Urinalysis / Q000295:instrumentation* / Q000379:methods*; D010879:Piperazines
chemical_list: D011804:Quinolines; C034759:piperaquine; D010879:Piperazines