Liao Chunhui, Qin Ziyi, Xu Jinju, Lan Tian, Shi Shuyun, Guo Ying
College of Chemistry and Chemical Engineering, Central South University, Changsha, 410083, Hunan, China.
Department of Clinical Pharmacology, Xiangya Hospital, Hunan Key Laboratory of Pharmacogenetics, Central South University, Changsha, 410078, Hunan, China.
Mikrochim Acta. 2025 May 29;192(6):386. doi: 10.1007/s00604-025-07158-1.
MnO nanozyme-based strategy is for the first time exploited for dual-mode colorimetric and fluorescence determination of antioxidant activity and HPLC - UV - MS/MS profiling of antioxidants. MnO nanosheets (MnO NS) with outstanding oxidase-like property can trigger rhodamine B (RhB) chromogenic reaction, leading to design an accurate, selective, and sensitive dual-mode colorimetric and fluorescence method for total antioxidant capacity (TAC) determination. Additionally, antioxidants in complex extract can react with MnO NS catalytic reactive oxygen species (ROS) intermediates (•O and O), which deduced the HPLC peaks decreased or disappeared. And screened antioxidants can be identified by MS/MS analysis. As proof of concept, antioxidant levels of four flavonoids (quercetin, rutin, hesperidin, and nobiletin) with different substituent groups and six samples (peels, pulps, and juices for two citrus cultivars ChunJian tangerine and Debao navel orange) were successfully measured. Nineteen flavonoids with ROS scavenging activity from citrus samples have been screened out and characterized. Especially, polymethoxyflavones, nonactive in DPPH•/ABTS•-based assays, presented certain ROS scavenging activity. Together, this study provided a novel and efficient platform to accurately and selectively measure and screen physiological antioxidants in real complex samples, revealing its great promise and convenient applications in future.
基于MnO纳米酶的策略首次被用于抗氧化活性的双模式比色法和荧光法测定以及抗氧化剂的HPLC - UV - MS/MS分析。具有出色类氧化酶性质的MnO纳米片（MnO NS）可引发罗丹明B（RhB）显色反应，从而设计出一种准确、选择性高且灵敏的双模式比色法和荧光法来测定总抗氧化能力（TAC）。此外，复杂提取物中的抗氧化剂可与MnO NS催化的活性氧（ROS）中间体（•O和O）发生反应，这导致HPLC峰减少或消失。并且通过MS/MS分析可鉴定筛选出的抗氧化剂。作为概念验证，成功测定了具有不同取代基的四种黄酮类化合物（槲皮素、芦丁、橙皮苷和川陈皮素）以及六个样品（两个柑橘品种春见蜜橘和德保脐橙的果皮、果肉和果汁）中的抗氧化剂水平。已从柑橘样品中筛选并鉴定出19种具有ROS清除活性的黄酮类化合物。特别是，在基于DPPH•/ABTS•的测定中无活性的多甲氧基黄酮表现出一定的ROS清除活性。总之，本研究提供了一个新颖且高效的平台，用于准确、选择性地测量和筛选实际复杂样品中的生理性抗氧化剂，揭示了其在未来的巨大潜力和便捷应用。
