title: Dried blood spot assay for estimation of metronidazole concentrations in rats and its application in single animal drug pharmacokinetic study.
abstract: An HPLC-UV-dried blood spot (DBS) method for the estimation of metronidazole (MTZ) in rat whole blood is reported. Method employs Ahlstrom 226 sample collection paper and DBS samples were prepared by spotting with 30 μl of whole blood (spiked calibration standards/quality control samples/in vivo study samples). A 6mm disc was punched from each DBS and extraction was carried out using water containing the internal standard (tinidazole). The calibration for MTZ was linear over 2.5-50 μg/ml concentration range. Accuracy (% bias) and precision (expressed as % Coefficient of variation) values for within and between day were <20% at the lower level quality control sample (LQC) and <15% at all other concentrations tested. The limit of quantification (LOQ) of the method was 2.5 μg/ml. The validated method was applied for the analysis of in vivo pharmacokinetic (PK) study samples after intravenous administration of MTZ to a rat. Whole blood PK parameters observed in this study were in compliance with literature based PK parameters. The DBS sampling approach was found to be useful in a single animal pharmacokinetic study.
authors.affiliation: PKPD Core Facility, School of Pharmacy, Medical Biology Centre, Queen’s University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom. prashantkole@gmail.com
authors.forename: Prashant Laxman
authors.initials: PL
authors.lastname: Kole
authors.forename: Rita
authors.initials: R
authors.lastname: Majithia
authors.forename: Thakur Raghu Raj
authors.initials: TR
authors.lastname: Singh
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Garland
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Migalska
authors.forename: Ryan F
authors.initials: RF
authors.lastname: Donnelly
authors.forename: James
authors.initials: J
authors.lastname: McElnay
mesh_terms: D000818:Animals; D001800:Blood Specimen Collection; D002851:Chromatography, High Pressure Liquid; D003890:Desiccation; D016018:Least-Squares Analysis; D008795:Metronidazole / Q000097:blood* / Q000493:pharmacokinetics; D051381:Rats; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014011:Tinidazole / Q000032:analysis
chemical_list: D014011:Tinidazole; D008795:Metronidazole