Fast, selective, and sensitive ultra-high performance liquid chromatography method with tandem mass spectrometry detection for the determination of quercetin and its metabolites with various physico-chemical properties such as molecular weight, lipophilicity, and acid-base properties has been developed. These compounds included small hydrophilic phenolic acids and more lipophilic metabolites with preserved flavonoid structure in small amount of rat plasma. The developed method enables selective separation of phenolic acids and a pair of isomers tamarixetin and isorhamnetin with satisfactory peak shapes and a high sensitivity using mass spectrometry detection. In addition, two sample preparation procedures including protein precipitation and microextraction in packed sorbent (MEPS) were optimized. The sample acidification included in protein precipitation as well as optimizing of MEPS sorbents and elution solvents improved isolation of quercetin and related compounds from rat plasma. Finally, both methods developed for sample preparation were fully validated to demonstrate sufficient accuracy and precision and acceptable matrix effects. Both sample preparation approaches combined with mass spectrometry-based quantification allowed the simultaneous determination of quercetin and its metabolites from a small amount of biological samples of only 50 μL. Due to the fast and non-selective parallel sample preparation, the protein precipitation was eventually applied to plasma samples derived from pharmacokinetic studies.

已经开发了一种快速，选择性和灵敏的串联质谱检测超高效液相色谱法，用于测定槲皮素及其代谢物，这些槲皮素及其代谢物具有多种理化性质，例如分子量，亲脂性和酸碱性质。这些化合物在少量大鼠血浆中包括小的亲水性酚酸和更多的具有保留类黄酮结构的亲脂性代谢物。所开发的方法能够通过质谱检测法选择性分离酚酸和一对异构体他马西汀和异鼠李素，并具有令人满意的峰形和高灵敏度。此外，还优化了两种样品制备程序，包括蛋白质沉淀和装填吸附剂（MEPS）中的微萃取。蛋白质沉淀中的样品酸化以及MEPS吸附剂和洗脱溶剂的优化改善了从大鼠血浆中分离槲皮素和相关化合物的能力。最后，为样品制备开发的两种方法均经过充分验证，以证明足够的准确性和精密度以及可接受的基质效应。两种样品前处理方法与基于质谱的定量方法相结合，可从少量仅50μL的生物样品中同时测定槲皮素及其代谢物。由于快速且非选择性的平行样品制备，最终将蛋白质沉淀应用于源自药代动力学研究的血浆样品。