Cheng Xiaoliang, Liu Kunhong, Liu Yong, Wang Maoyi, Ma Ying
Department of Pharmacy, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China.
School of Pharmacy, Nanchang University, Nanchang, China.
Rapid Commun Mass Spectrom. 2018 Jul 15;32(13):1068-1074. doi: 10.1002/rcm.8100. Epub 2018 May 27.
A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for quantification of caspofungin in dried blood spots (DBS) was developed and validated.
The DBS samples were prepared by spotting whole blood onto Whatman 903 filter paper, drying at room temperature and extracting with 50% methanol and further cleaned by protein precipitation with acetonitrile. Roxithromycin was selected as internal standard, and the separation of the analytes with endogenous ingredients was accomplished on a Hypersil GOLD aQ column with a mobile phase composed of 0.1% formic acid (v/v) and methanol in gradient mode. The detection of the analytes was performed on a triple quadrupole mass spectrometer in positive electrospray ionization mode, and the following selective reaction monitoring (SRM) transitions were monitored: m/z 547.6 → 538.7 and 837.4→ 679.4 for quantification of caspofungin and the internal standard, respectively.
The total analytical time was 8 min for each run. The calibration curve exhibited a good linearity over the range from 0.2 to 20 μg/mL and the lower limit of quantification (LLOQ) was 0.2 μg/mL for caspofungin in DBS. The recoveries of caspofungin ranged from 62.64% to 76.69%, and no obvious matrix effect was observed. The intra- and inter-day precision and accuracy were within acceptable limits, and caspofungin in DBS was stable after storage at room temperature for 24 h and at -80°C for 30 days. There was no evident effect of the hematocrit value on the analysis of caspofungin.
The proposed method presents an alternative to the conventional venous sampling method, and was successfully utilized for pharmacokinetics study of caspofungin in ICU patients.
建立并验证了一种用于定量干血斑（DBS）中卡泊芬净的液相色谱/串联质谱（LC/MS/MS）方法。
通过将全血点样到沃特曼903滤纸上制备DBS样品，室温干燥，用50%甲醇萃取，再用乙腈进行蛋白沉淀进一步净化。选择罗红霉素作为内标，在Hypersil GOLD aQ柱上以梯度模式由0.1%甲酸（v/v）和甲醇组成的流动相实现分析物与内源性成分的分离。在三重四极杆质谱仪上以正电喷雾电离模式进行分析物检测，监测以下选择性反应监测（SRM）转换：分别用于定量卡泊芬净和内标的m/z 547.6→538.7和837.4→679.4。
每次运行的总分析时间为8分钟。校准曲线在0.2至20μg/mL范围内呈现良好线性，DBS中卡泊芬净的定量下限（LLOQ）为0.2μg/mL。卡泊芬净的回收率在62.64%至76.69%之间，未观察到明显的基质效应。日内和日间精密度及准确度均在可接受范围内，DBS中的卡泊芬净在室温下储存24小时和在-80°C下储存30天后稳定。血细胞比容值对卡泊芬净分析无明显影响。
所提出的方法为传统静脉采样方法提供了一种替代方法，并成功用于ICU患者中卡泊芬净的药代动力学研究。
