In the present study, we developed a simple and rapid analytical method for the quantification of bupivacaine hydrochloride in human biopsy samples of adipose, muscle, neural, connective and cartilage tissue using liquid chromatography-mass spectrometry. Anesthetics were extracted from the tissue samples using 0.1% formic acid in acetonitrile for protein denaturation and hexane for removal of lipophilic impurities. Analytes were separated adequately on Phenomenex Luna Omega polar C18 column using a gradient mobile phase 0.1% formic acid in water and 0.1% formic acid in acetonitrile. The lower limits of quantification were ≤ 97 ng g⁻¹ tissue for all studied tissues. Intra-day recoveries were between 48.2% and 82.1% with relative standard deviations (RSDs) between 1.47% and 14.28%, whereas inter-day recoveries were between 52.2% and 77.6% with RSDs between 2.98% and 14.79%. The calibration curve showed a linear fit with R² higher than 0.99 in the concentration range from 0.16 to 100 μg g⁻¹. Lidocaine hydrochloride was tested as internal standard because its recoveries and matrix effects were comparable to bupivacaine hydrochloride. Post-analytical corrections of measured bupivacaine tissue concentrations can accordingly be made based on recovery of lidocaine as internal standard, with recoveries between 51.2% and 86.9% and RSDs between 1.99% and 16.88%. The developed method could be used to study time-dependent spread of bupivacaine locally or to more distant locations across tissue barriers.

中文翻译：

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使用高效液相色谱和质谱法测定人体活检样本中的布比卡因组织浓度

在本研究中，我们开发了一种简单快速的分析方法，用于使用液相色谱-质谱法对人体脂肪、肌肉、神经、结缔组织和软骨组织活检样本中的盐酸布比卡因进行定量。从组织样本中提取麻醉剂，使用 0.1% 甲酸乙腈溶液进行蛋白质变性，使用己烷去除亲脂性杂质。在 Phenomenex Luna Omega 极性 C18 色谱柱上，使用 0.1% 甲酸水溶液和 0​​.1% 甲酸乙腈梯度流动相充分分离分析物。定量下限≤ 97 ng g ^-1组织用于所有研究的组织。日内回收率介于 48.2% 和 82.1% 之间，相对标准偏差 (RSD) 介于 1.47% 和 14.28% 之间，而日间回收率介于 52.2% 和 77.6% 之间，RSD 介于 2.98% 和 14.79% 之间。校准曲线显示线性拟合，R ²在 0.16 至 100 μg g ^-1的浓度范围内高于 0.99. 将盐酸利多卡因作为内标进行测试，因为其回收率和基质效应与盐酸布比卡因相当。因此，可以根据作为内标的利多卡因的回收率对测量的布比卡因组织浓度进行分析后校正，回收率介于 51.2% 和 86.9% 之间，RSD 介于 1.99% 和 16.88% 之间。开发的方法可用于研究布比卡因在局部或跨组织屏障到更远位置的时间依赖性传播。