RESUMEN
OBJECTIVE: To determine the bufalin concentration in rats' plasma by establishing a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method, and to evaluate and compare the pharmacokinetic characteristics of bufalin-loaded bovine serum albumin nanoparticles (bufalin-BSA-NP) and bufalin. METHODS: Thirty Wistar rats were randomly divided into six groups with five rats in each group, and administered with a single dose of 0.6, 0.3 and 0.15 mg/kg of bufalin-BSA-NP or bufalin, respectively. After the administration, blood samples were collected from the orbital venous plexus at designed time points (1, 5, 8, 10, 15, 20, 30, 45, 60, 120, 180, 300 and 480 min). The concentration of bufalin in plasma at different sampling time points was determined by HPLC-MS/MS. The pharmacokinetic parameters were calculated and compared. RESULTS: The established HPLC-MS/MS method had high linearity, precision and accuracy. The blood plasma area under curve, the mean retention time and the terminal half life of bufalin-BSA-NP were 1.19 to 1.81, 2.12 to 3.61 and 2.17 to 2.94 times of bufalin, respectively. CONCLUSION: Bufalin-BSA-NP has the function of sustained release thus to prolong the bufalin remaining in blood.