Development Of An Automatic On-line Solid Phase Extraction Column Switching Liquid Chromatography Tandem Mass Spectrometry System, And Its Application To Pharmacokinetic Study

AIM: To develop and optimize an automatic on-line solid phase extraction column switching LC/MS/MS systerm for quantitation of puerarin in biomatrix samples, and to study the non-clinical pharmacokinetics of puerarin phospholipid complex after po administration in beagles.METHODS: Puerarin was analyzed by the automatic on-line solid phase extraction column switching LC/MS/MS systerm with a linear ion trap mass spectrometer, LTQ-MS, operating in selective reaction monitoring (SRM) acquisition mode. The SRM detection setup for the analyte peurarin was m/z 415.3→295.2 PK parameters were caculated by non-comparment model statistical moment.RESULTS AND CONCLUSIONS: 1. The automatic on-line SPE-LC/MS/MS system to quantitates puerarin in serum samples, is on-line spilling injection mode, SPE extraction column was a narrow I.D. column(50 mm×2.1 mm I.D.), packed with Zorbax C₁₈, and this systerm needed no complicated pretreatment procedures of samples. The single run time of an individual sample was 6.5 min. 2. The analytical speed of the automatic on-line SPE-LC/MS/MS system was rapid, and the specificity, linearity, sensitivity, precision and stability of the methodology reached the requirements of PK study. Results showed that the developed method was feasible and reliable to be applied in preclinical or clinical PK studies of puerarin. 3. After a single po administration of puerarin phospholipid complex at different dosage levels in beagles, the maximum concentration (C_max) and the area under concentration-time curve (AUC) exhibited a parallel manner depending on different dosage levels, but there was difference between intermediate and high dosage levels of t_1/2, and low dosage level of CL existed different from intermediate and high dosage levels of CL, which indicated that the pharmacokinetics of the puerarin phospholipid complex behaved a non-linear characteristic within the dosage range studied. 4. After po administration at 220 mg·kg^-1 PLC for 3 consecutive days (once daily), there was little difference between the serum puerarin concentrations of the same time points after the first or the last dose (P > 0.05), and the same was PK parameters (P > 0.05). It suggested that there was no accumulation tendency after multiple doses via the given dosage, route and the times. 5. The average bioavailability of PLC aftrer po administration at 55 mg·kg^-1 PLC was about 15.7±3.8...