Automated determination of a novel anti-inflammatory drug in plasma using batch robotic sample preparation and HPLC

摘要

A Zymark XP Robot has been adapted to extract a novel anti-inflammatory drug (CI-1004) and internal standard (IS) from rat plasma using a batch robotic solid-phase extraction system. Under computer control, the robot automatically conditions, loads, washes, and elutes up to 144 solid-phase cartridges in parallel. The system incorporates a miniature pressure transducer to monitor and control manifold vacuum, thereby controlling solvent flow through the cartridges. Liquid chromatographic separation was achieved isocratically on a Zorbax Rx-C8 analytical column (4.6 mm i.d. × 250 mm). Mobile phase consisted of 65:35 (v/v) acetonitrile and 20 mM ammonium acetate (pH = 4.0). Column effluent was monitored spectrophotometrically at 360 nm. Specificity, chromatographic performance parameters, system repeatability, recovery from matrix, linearity, precision, and accuracy were evaluated. No interfering peaks were observed at the retention time of CI-1004 throughout the validation process. Peak-height ratios were proportional to CI-1004 in rat plasma over the concentration range of 7.5-5000 ng/mL. The system is capable of extracting 100 plasma samples in approximately 5 hours. © 1996 John Wiley & Sons, Inc.