Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Clinical Pharmacology of Antibiotics, Health and Family Planning Commission, Shanghai, China; National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China.
Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China; Key Laboratory of Clinical Pharmacology of Antibiotics, Health and Family Planning Commission, Shanghai, China; National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2022 Mar 1;1192:123131. doi: 10.1016/j.jchromb.2022.123131. Epub 2022 Feb 2.
Polymyxin B, a last line antibiotic for extensively drug resistant gram-negative bacteria, therapeutic drug monitoring (TDM) is recommended to minimize its nephrotoxicity and improve efficacy. In the present study, we developed a novel quantification method of polymyxin B in dried blood spots (DBS) using liquid chromatography coupled with mass spectrometry (LC-MS/MS), which was performed on a Shimadzu Prominence HPLC system coupled with a 4500 triple quadrupole mass spectrometer. An aliquot of 50 μL whole blood sample was spotted on Whatman 903® paper cards. Each DBS sample was cut off into a 6 mm diameter disc and extracted by acetonitrile in water (30% in volume, containing 6% formic acid, v/v). Both intra and inter-batch accuracy was in the range of 92.6%-111.0% for polymyxin B1 and 91.5%-111.5% for polymyxin B2. The precision was in the range of 5.2%-12.2% for polymyxin B1 and 4.9%-13.1% for polymyxin B2. The matrix effects for polymyxin B1 and polymyxin B2 at low, medium and high concentrations were ranged from 102.2%-107.9% and 99.8%-106.2%, respectively. The extraction recoveries were >85.4%. Stability results showed that DBS cards can be transported at room temperature within 2 days and was stable in sealed plastic bags for 38 days at -70 °C. Bland-Altman analysis demonstrated that concentrations of polymyxin B measured in DBS and plasma methods were in moderate agreement with 95.1% samples within the 95% confidence interval of limits of agreement. The DBS method was successfully applied in clinic for TDM of polymyxin B, which can be an alternative approach in clinic.
多粘菌素 B 是一种用于治疗广泛耐药革兰氏阴性菌的最后一线抗生素，推荐进行治疗药物监测 (TDM) 以最大程度降低其肾毒性并提高疗效。本研究建立了一种新的多粘菌素 B 在干血斑 (DBS) 中的定量方法，采用液相色谱-串联质谱 (LC-MS/MS) 进行分析，该方法在 Shimadzu Prominence HPLC 系统上与 4500 三重四极杆质谱联用。取 50 μL 全血样本点在 Whatman 903® 滤纸卡上。每个 DBS 样本切成 6mm 直径的圆片，用乙腈-水 (体积比 30%，含 6%甲酸，v/v) 提取。多粘菌素 B1 和多粘菌素 B2 的批内和批间准确度均在 92.6%-111.0%范围内，精密度均在 5.2%-12.2%范围内。多粘菌素 B1 和多粘菌素 B2 的低、中、高浓度的基质效应分别在 102.2%-107.9%和 99.8%-106.2%范围内。提取回收率均大于 85.4%。稳定性结果表明，DBS 卡可在室温下运输 2 天，在 -70°C 下密封塑料袋中可稳定 38 天。Bland-Altman 分析表明，DBS 和血浆方法测定的多粘菌素 B 浓度在 95%置信区间的限差内有 95.1%的样品具有中等一致性。该 DBS 方法已成功应用于多粘菌素 B 的 TDM，可作为临床替代方法。
