Bioanalysis of six antibiotics from volumetricmicrosamples: a new tool for precisiondosing in critically ill children: supplementary materials

Background: Volumetric absorptive microsamples (VAMS) can support pharmacokinetic /
pharmacodynamic studies. We present the bioanalytical method development for the simultaneous
quantification of ampicillin, cefepime, ceftriaxone, meropenem, piperacillin, tazobactam , and
vancomycin from VAMS. Methods & results: Optimal extraction, chromatographic , andmass spectrometry
conditions were identified. Maximum extraction recoveries included 100 μl of water for rehydration and
methanol for protein precipitation. Chromatographic separation used Phenomenex Kinetex™ Polar C18
column with a mobile phase comprising water/acetonitrile with formic acid and was fully validated.
Hematocrit effects were only observed for vancomycin. Samples were stable for 90 days at -80◦C except
for meropenem, which was stable for 60 days. Conclusion: Multiple antibiotics can be assayed from a
single VAMS sample to facilitate pharmacokinetic/pharmacodynamic studies.

背景：体积吸收微量取样（Volumetric absorptive microsamples, VAMS）可用于支持药代动力学/药效动力学研究。本研究针对从VAMS样本中同时定量测定氨苄西林、头孢吡肟、头孢曲松、美罗培南、哌拉西林、他唑巴坦及万古霉素的生物分析方法开发进行了阐述。方法与结果：研究确定了最优的提取、色谱及质谱分析条件。当采用100 μL水进行复溶、甲醇进行蛋白沉淀时，可获得最高的提取回收率。色谱分离采用菲罗门Kinetex™ Polar C18色谱柱，流动相为含甲酸的水/乙腈体系，该方法已完成完整验证。仅万古霉素受血细胞比容影响。样本在-80℃下可稳定保存90天，美罗培南除外，其仅可稳定保存60天。结论：仅需单个体积吸收微量取样样本，即可完成多种抗生素的含量测定，可为药代动力学/药效动力学研究提供便利。