Vanillic acid, a phenolic compound isolated from Angelica sinensis and green tea, exhibits excellent antioxidant and anti-inflammatory activities. In this study, a rapid and sensitive ultra-high-performance liquid chromatography tandem mass spectrometry method was established and validated for the determination of vanillic acid in rat plasma. Plasma samples were prepared by protein precipitation with acetonitrile. Chromatographic separation was performed on a Zorbax RRHD Eclipse Plus C₁₈ column (2.1 × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.3 ml/min, using mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). Vanillic acid and caffeic acid (internal standard, IS) were quantified by multiple reaction monitoring in negative ion mode. The method was fully validated according to the US Food and Drug Administration guidelines. The calibration curve was linear over the range of 2–1,000 ng/ml with a correlation coefficient of >0.99. The carryover, matrix effect, extraction recovery, dilution effect, intra- and interday precision and accuracy were within acceptable limits. The method was then applied to a pharmacokinetic study of vanillic acid in rats. After oral administration at doses of 2, 5 and 10 mg/kg, the plasma concentration reached peaks of 0.42 ± 0.09, 0.73 ± 0.21 and 0.92 ± 0.28 μg/ml at the time of 0.55–0.64 h, respectively. The oral bioavailability was calculated as 25.3–36.2% in rat plasma. The result provided pre-clinical information for further application of vanillic acid.

中文翻译：

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一种快速灵敏的 LC-MS/MS 方法测定大鼠血浆中香草酸及其药代动力学研究

香草酸是一种从当归和绿茶中分离出来的酚类化合物，具有出色的抗氧化和抗炎活性。本研究建立并验证了一种快速灵敏的超高效液相色谱串联质谱法用于大鼠血浆中香草酸的测定。通过用乙腈沉淀蛋白质来制备血浆样品。_{在 Zorbax RRHD Eclipse Plus C 18}上进行色谱分离色谱柱 (2.1 × 100 mm, 1.8 μm)，梯度洗脱，流速为 0.3 ml/min，流动相由 0.1% 甲酸 (A) 和乙腈 (B) 组成。香草酸和咖啡酸（内标，IS）通过负离子模式下的多反应监测进行定量。该方法已根据美国食品和药物管理局指南进行了充分验证。校准曲线在 2–1,000 ng/ml 范围内呈线性，相关系数 >0.99。残留、基质效应、萃取回收率、稀释效应、日内和日间精密度和准确度均在可接受的范围内。然后将该方法应用于大鼠中香草酸的药代动力学研究。以2、5和10 mg/kg剂量口服给药后，血浆浓度达到峰值0.42±0.09、0.73±0.21和0.92±0。在 0.55-0.64 小时时分别为 28 μg/ml。大鼠血浆中的口服生物利用度计算为 25.3-36.2%。该结果为进一步应用香草酸提供了临床前信息。