摘要
Benapenem is a new parenteral beta-lactam antibacterial with a broad antibacterial spectrum. In the present study, we developed and validated a simple, rapid and sensitive assay method using D6-benapenem as internal standard(IS) after one-step precipitation with methanol to determine benapenem in the plasma of infected mice. Separation was achieved on a reverse phase C18 column with a mobile phase composed of acetonitrile containing 0.2% formic acid–water(0.2% formic acid) and 10 mmol/L ammonium acetate in gradient elution mode. A triple quadrupole tandem mass spectrometer with electrospray ionization source was used as detector and operated by multiple reaction monitoring(MRM) in the positive ion mode. Calibration curves were linear(r>0.99) between 10 and 2000 ng/m L. The quantitative limit was 10 ng/m L, and the intra-and inter-precisions were <4.85% and <1.47%, respectively. The extraction recovery of benapenem and IS was 97.07%–107.09% and 92.47%–111.59%, respectively. The intra-and inter-accuracies were –9.70%– –11.00%, and the matrix effects of benapenem and IS were 85.68%–92.04% and 83.17%–92.04%, respectively. The method was successfully applied to the preclinical pharmacokinetic(PK) studies of benapenem. We also developed a two-compartment model to characterize the PK profiles of benapenem in infected mice, which could provide a better understanding of the PK properties of benapenem.
百纳培南是一类新型的广谱β-内酰胺类经肠外给药抗菌药物。本研究建立了一种简便、快速、灵敏的液质联用方法用于测定感染小鼠血浆中百纳培南的浓度。采用百纳培南氘代内标,血浆样品经甲醇进行蛋白沉淀处理后,采用乙腈(含0.2%甲酸)–10 m M乙酸铵溶液(含0.2%甲酸)作为流动相,采用C18反相色谱柱进行梯度洗脱分离。使用三重四级杆串联质谱,电喷雾正离子模式、多反应监测技术进行检测。标准曲线在10~2000 ng/m L范围内线性良好(r>0.99),定量下限为10ng/m L,批内及批间精密度分别<4.85%和<1.47%。百纳培南和内标的提取回收率分别为97.07%~107.09%和92.47%~111.59%。批内及批间准确度为–9.70%~–11.00%,百纳培南和内标的基质效应分别为85.68%~92.04%和83.17%~92.04%。该方法已成功应用于百纳培南的临床前药代动力学研究。此外,我们还建立了一个二室模型来描述百纳培南在感染小鼠体内的药物动力学行为,以更好地了解其药动学特征。
基金
National Natural Science Foundation of China(Grant No.81803614)
