Revista de técnicas analíticas y bioanalíticas

Abstracto

A Novel Method for Determination of Fenofibric Acid in Human Plasma using HPLC-UV: Application to a Pharmacokinetic Study of New Formulations

Iltaf Shah, James Barker, Stephen J Barton and Declan P Naughton

A high performance liquid chromatography method for the determination of fenofibric acid (FA), the active form of fenofibrate (FBT) in human plasma was developed and validated with 500 μL of human plasma using 4’-chloro- 5-fluro-2-hydroxybenzophenone (CFHB) as internal standard (IS). The assay procedure involved a simple one step liquid/liquid extraction of FA and IS from human plasma into ethyl acetate. The organic layer was separated and evaporated under a gentle stream of nitrogen at 40°C. The residue was reconstituted in the mobile phase and injected on a Symmetry ShieldïÂ?Â?RP18 (150×4.60 mm) 5 μm column. Separation of FA and IS was achieved with a mobile phase consisting of acetonitrile: 0.02 M phosphoric acid (50:50 v/v) at a flow rate of 1 mL/min. Nominal retention times of FA and IS were 6.1 and 9.1 ± 0.5 min, respectively. Absolute recovery of FA using a single step liquid/liquid method was 79.8%. A calibration curve was established for a range of concentrations 0.05 to 10.0 μg/mL with a regression coefficient (r2) of 0.9988. The lower limit of quantification (LLOQ) of FA was 0.05 μg/mL. The intraand inter-day precision for the measurement of FA quality control samples (0.05, 0.12, 1.20 and 8.20 μg/mL), were in the range 4.6-16.9% and 4.4-17.2% relative standard deviations respectively. The accuracy in the measurement of QC samples for FA was in the range of 82.0-104.3% (intra-day) to 95.0-104.9% (inter-day). The method developed was successfully used to investigate the pharmacokinetics and bioequivalence between a micronized Lipidil-Micro™ capsule formulation and a nanonised fenofibrate Lipidil-EZ™ tablet formulation.