A Simple HPLC Bioanalytical Method for the Determination of Doxorubicin Hydrochloride in Rat Plasma: Application to Pharmacokinetic Studies

Purpose: To develop a simple, accurate, and precise high performance chromatography (HPLC) method with spectrophotometric detection for the determination of doxorubicin hydrochloride in rat plasma.
Methods: Doxorubicin hydrochloride and daunorubicin hydrochloride (internal standard, IS) were separated on a C₁₈ reversed-phase HPLC column. Following protein precipitation extraction, chromatographic separation was accomplished with a mobile phase consisting of acetonitrile: water at ratio of 30:70 (pH 3.0), and the drug was detected at 233 nm using a UV detector at flow rate of 1.0 ml/min and ambient temperature.
Results: Linearity was obtained over the range 1.0 – 50.0 μg/ml for doxorubicin hydrochloride with lower limit of quantitation of 1.0 μg/ml. For each level of quality control samples, inter- and intra-day precision (% CV) was < 9.6 and 5.1 %, respectively. Stability of doxorubicin hydrochloride in plasma was within the acceptance limit (± 15 %) with no evidence of degradation during sample processing and 30 days storage in a deep freezer at -70 ± 5 °C. Absolutes extraction recovery of drug from plasma was ≥ 86 %.
Conclusion: The method is highly selective and rugged for the determination of doxorubicin hydrochloride in rat plasma and should be suitable for conducting pharmacokinetic studies and therapeutic drug monitoring.