ABSTRACT
OBJECTIVE: To develop a sensitive and specific LC-MS/MS method for the determination of pilsicainide in human plasma and urine. METHODS: The samples were processed by LLE(liquid-liquid extraction), acetonitrile-ammonium acetate(0.1‰ formic acid)-water was used as the mobile phase with isocratic elution(25:37.5:37.5 in plasma, 35:6:59 in u-rine), and separation was carried out on Welch Material Ultimate AQ-C18 column(2.100 × 100 mm, 3.5 μm), setting the flow rate as 0.35 mL · min-1, the column temperature at 25°C. The injection volume was 5 μL. ESI under positive ion mode and multiple reaction monitoring scan(MRM) were used for quantitative analysis with m/z 213.4 → 110.2 for pilsicainide and m/z 287.4 → 110.2 for internal standard, methyl-pilsicainide. RESULTS: The linear ranges of the calibration curves for pilsicainide were 1-1200 μg · L-1 for plasma and 1-150 mg · L-1 for urine. The limitation of detection were 1 μg · L-1 for plasma and 1 mg · L-1 for urine. The correlation coefficient was between 0.9962 and 0.9991. The extraction recoveries, matrix effects, and intra-/inter-assay precisions all met the requirements of pharmacokinetic studies. This approach was applied to determine pilsicainide concentrations in human plasma and urine in a clinical pharmacokinetic research. CONCLUSION: This approach possesses convenience, accuracy, high sensitivity and good reproducibility, which can meet the requirements of pharmacokinetic studies.
ABSTRACT
OBJECTIVE:To establish a RP-HPLC analytical method for the determination of pazufloxacin mesilate in human plasma and urine.METHODS:The plasma proteins were precipitated with methanol and the supernatant liquid ob-tained from the serum centrifugate was subjected to chromatographic analysis.The supernatant liquid obtained from the diluted urine centrifugate was subjected to sample introduction.The analytical column was Diamonsil C 18 ,the mobile phase consisted of acetonitrile-0.05mol/L potassium dihydrogen phosphate(containing1%tetrabutylammonium bromide)(8∶92,V/V)with a flow rate at1.4ml/min,excitation wavelength at320nm and emission wavelength at400nm.RESULTS:The linear range of pazufloxacin mesilate in both plasma and urine was31.25～10000ng/ml(r=0.9999).The relative recoveries of pazu-floxacin mesilate in human plasma and urine were97.77%～99.87%and98.31%～100.82%,respectively with RSD less than1.0%～3.0%.CONCLUSION:This method is accurate,reliable and simple and it is suitable for the pharmacokinetic study and routine monitoring of blood concentration of pazufloxacin mesilate.
ABSTRACT
OBJECTIVE:To study the pharmacokinetics of balofloxacin tablets in Chinese healthy volunteers.METHODS:A single dose of 100 or 200 mg balofloxacin tablets were given to 12 healthy volunteers in a randomized crossover design.Concentrations of balofloxacin in plasma and urine were determined by HPLC with data processed by DAS(drug and statistics)software.RESULTS:After administration of balofloxacin 100 mg and 200 mg,the Cmax were(0.970?0.245)?g?mL-1 and(1.849?0.466)?g?mL-1;the tmax were(1.25?1.10)h and(1.24?0.81)h;the t1/2 were(7.14?1.01)h and(7.11?0.72)h;the AUC0～36 were(7.309?1.368)?g?h?mL-1 and(15.214?1.727)?g?h?mL-1;AUC0～∞ were(7.531?1.386)?g?h?mL-1 and(15.695?1.762)?g?h?mL-1;the accumulative eliminating rates within 36 h in urine were(64.47?11.56)% and(63.24?11.93)%,respectively.CONCLUSION:The pharmacokinetics of balofloxacin in healthy volunteer after oral administration was characterized by high peak concentration and long half life.The method is sensitive,accurate,reliable and specific,and can satisfy the requirements for pharmaceutical study.