Validation of an HPLC method for determination of pentoxifylline in human plasma and its application to pharmacokinetic study.

ABSTRACT

An HPLC method suitable for routine determination of pentoxifylline in human plasma has been adapted and validated. Sample preparation was done by solid-phase extraction. Chloramphenicol was used as the internal standard. The linear range was from 15-400 ng/mL (r2 = 0.9994), with a limit of quantitation of 15 ng/mL. The limit of detection was found to be 5 ng/mL. The intra- and interday accuracy ranged from 98.0 to 110.2% and the coefficient of variation was not more than 8.8% for both intra- and interday precision. The absolute recoveries of pentoxifylline and chloramphenicol from human plasma were >97%. The method was validated with excellent specificity, accuracy, precision, recovery, and stability. The pharmacokinetic study of a generic pentoxifylline 400 mg tablet in healthy Thai male volunteers after a single dose administration was determined by this developed assay.