Determination of manassantin B in rat plasma using a high performance liquid chromatography with fluorescence detection and its quantitative application to pharmacokinetic study

• A simple and sensitive analytical method of manassantin B in plasma was developed.
• HPLC with fluorescence detector was adopted for its quantitative analysis.
• Precision and accuracy values in all tests were within the acceptable ranges.
• Developed method was successfully applied to pharmacokinetic study in rats.

A simple, sensitive, rapid, and reproducible analytical method of manassantin B in rat plasma by high performance liquid chromatography with fluorescence detection (HPLC-FL) was developed for its application to pharmacokinetic study in rats. Valsartan (VST) was used as an internal standard (IS) in this quantitative analytical method. Manassantin B and VST were extracted by simple and efficient protein precipitation method. Manassantin B was detected at 282/322 nm (excitation/emission) wavelengths using FL detector. The chromatographic separation was obtained with reverse phase C18 column and the mobile phase composed of potassium phosphate buffer containing 0.025% trifluoroacetic acid (pH 2.5; 5 mM) and acetonitrile including 0.025% trifluoroacetic acid (20:80, v/v) at 1.0 mL/min flow rate. The linearity was established at 25.0–10000 ng/mL and the lower limit of detection (LLOD) was 7 ng/mL. The intra- and inter-day accuracy and precision values of manassantin B were within ± 15% of the theroretical values and <9% from the nominal concentrations, respectively. Accuracy and precision values of manassantin B after stability tests were also within the acceptable ranges. Developed assay was also successfully applied to pharmacokinetic study after intravenous administration of manassantin B in rats.