Natural products with aggregation-induced emission properties: from discovery to their multifunctional applications

来自于天然产物的聚集诱导发光(AIE)材料具有无需化学合成、生物兼容性好、天然可降解、药理活性等优点, 正在逐渐成为环境监测、生物成像和疾病诊断等领域的有力工具. 本文综述了目前从天然产物中发现的AIE材料, 包括黄连素等生物碱、槲皮素等类黄酮多酚、丹宁酸等非类黄酮多酚以及其他皂苷、维生素等天然化合物. 这些材料的发光机制主要有分子运动受限(RIM)、扭转分子内电荷转移(TICT)、激发态分子内质子转移(ESIPT)、J-聚集、簇发光(CTE)等. 基于显著的AIE特性, 这些天然产物表现出在pH、离子及生物标志物传感、细胞成像和生物诊疗等领域的巨大应用潜力. 期望本文能够加深对聚集诱导发光现象的理解, 启发对来源于天然产物的AIE分子的探索及新应用的开发. Aggregation-induced emission (AIE) materials derived from natural products have the advantages of non-synthetic, good biocompatibility, natural degradation and pharmacological activity, and are gradually becoming a powerful tool in environmental monitoring, biological imaging and disease diagnosis. Here, we review AIE materials discovered from natural products, including alkaloids such as berberine, flavonoid polyphenols such as quercetin, non-flavonoid polyphenols such as tannic acid, and other natural compounds such as saponins and vitamins. AIE mechanisms of these materials include restriction of intramolecular/intermolecular motion (RIM), torsional intramolecular charge transfer (TICT), excited state intramolecular proton transfer (ESIPT), J-aggregate and clusterization-triggered emission (CTE). Based on remarkable AIE properties, these natural products show great potential in the fields of pH, ion and biomarker sensing, cell imaging and biological diagnosis and treatment. This paper is expected to deepen the understanding of aggregation-induced luminescence, inspire the exploration of AIE molecules from natural products and develop new applications. © 2022 Scientia Sinica Chimica. All rights reserved.