The purpose of this work was to develop and validate an HPLC-MS/MS method suitable for quantifying two important cardiovascular drugs, milrinone and dobutamine, in neonatal and paediatric patients’ blood plasma samples. Sufficiently low LLOQ levels were required to obtain adequate pharmacokinetic data for the evaluation of optimal dosing. Since the specifics of the patient group set some restrictions on the available sample volume, the method was designed to use only 20 µL of plasma for the analysis. Analytes were separated chromatographically in a biphenyl column using a conventional water-methanol-formic acid eluent with the addition of ammonium fluoride. The latter provided a significant signal enhancement in positive ion mode detection for both analytes allowing the LLOQ to reach below 1 ng/mL. Matrix matched calibration was linear in the range of 1–300 ng/mL, between-run accuracy remained within 107–115%, and precision within 4.8–7.4% for both analytes over the calibration range (including LLOQ level). Dobutamine degradation in plasma samples was prevented by the usage of ascorbic acid. The method was applied to plasma samples of neonates from two pharmacokinetic/pharmacodynamics studies (n = 38).

这项工作的目的是开发和验证一种 HPLC-MS/MS 方法，适用于定量新生儿和儿科患者血浆样本中两种重要的心血管药物米力农和多巴酚丁胺。需要足够低的 LLOQ 水平才能获得足够的药代动力学数据来评估最佳剂量。由于患者组的具体情况对可用样本量设置了一些限制，因此该方法设计为仅使用 20 µL 血浆进行分析。在联苯柱中使用常规的水-甲醇-甲酸洗脱液并添加氟化铵对分析物进行色谱分离。后者在正离子模式检测中为两种分析物提供了显着的信号增强，使 LLOQ 达到 1 ng/mL 以下。基质匹配校准在 1–300 ng/mL 范围内呈线性，运行间准确度保持在 107–115% 范围内，两种分析物在校准范围（包括 LLOQ 水平）内的精密度在 4.8–7.4% 范围内。使用抗坏血酸可以防止血浆样品中的多巴酚丁胺降解。该方法适用于两项药代动力学/药效学研究 (n = 38) 的新生儿血浆样本。