文献类型：期刊文献

英文题名：An AIE-active probe for monitoring calcium-rich biological environment with high signal-to-noise and long-term retention in situ

作者：Li, Xiangyu[1,2];Pan, Chao[1,2];Cao, Jun[3];Liu, Zhenxing[1,2];Zhu, Zhirong[1,2];Yan, Chenxu[1,2];Zhao, Weijun[1,2];Zhu, Wei-Hong[1,2];Wang, Qi[1,2,4]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Inst Fine Chem, Feringa Nobel Prize Scientist Joint Res Ctr, Frontiers Sci Ctr Materiobiol & Dynam Chem,Sch Che, Shanghai 200237, Peoples R China;[3]Dahua Hosp, Dept Intervent Oncol, Shanghai 200237, Peoples R China;[4]East China Univ Sci & Technol, Shanghai 200237, Peoples R China

年份：2022

卷号：289

外文期刊名：BIOMATERIALS

收录：;EI(收录号：20223912799483);WOS:【SCI-EXPANDED(收录号:WOS:000863454600001)】；

基金：This work was supported by National Key Research and Development Program of China (2021YFA0910000), NSFC Science Center Program (21788102), NSFC/China (22222803, 91959202, and 21974047), Shanghai Municipal Science and Technology Major Project (2018SHZDZX03).

语种：英文

外文关键词：Fluorescence imaging; Aggregation-induced emission; Overloaded calcium probe; Long-term retention; Bone microfracture

摘要：Fluorescent probe is a first-line method for qualitative and quantitative detection of calcium ions (Ca2+) in or-ganisms. However, the high affinity and aggregate-caused quenching (ACQ) characteristics of commercially available probes have restricted the detection limit to low concentrations from nM to mu M, unavailable to detect higher Ca2+ concentrations from mu M to mM in situ. Here, we develop a Ca2+ probe of TCM-4COOH with aggregation-induced emission (AIE) activity and desirable affinity, exhibiting a linear response to concentrated Ca2+ at mM level. The rapid binding between the TCM-4COOH and Ca2+ results in dramatic enhancement in fluorescence with high S/N ratio, and the nature that the chelates are not easy to diffuse from the cells endows the probe with long-term imaging ability in organisms. In the molecular design, the multiple iminodiacetic carboxyl groups ensure the good water solubility and pH biocompatibility of TCM-4COOH, resulting in negligible background fluorescence and high signal-to-noise (S/N) ratio. Moreover, the relatively dispersed carboxyl groups and the electron-withdrawing effect of TCM building block jointly adjust the probe affinity to Ca2+, thereby broadening the upper detection limit. In addition, to obtain better cell membrane penetrability, TCM-4COOH was modified with acetoxymethyl ester, which unit can be cleaved by endogenous esterase to release TCM-4COOH, so as to detect intracellular calcium ions. Benefit from the reasonable design of fluorophore and chelating groups, the AIE-active sensor TCM-4COOH can achieve long-term in-situ retention in visualizing calcium-overloaded cells and bone microcracks, especially providing a unique platform to broaden the upper limit of Ca2+ detection in biological environments.