Shen Jiajia, Shao Kuanchun, Zhang Wenlong, He Yaning
Department of Chemical Engineering, Key Laboratory of Advanced Materials (MOE), Tsinghua University, Beijing 100084, China.
ACS Macro Lett. 2021 Jun 15;10(6):702-707. doi: 10.1021/acsmacrolett.1c00183. Epub 2021 May 19.
In recent years, stimuli-responsive in situ self-assembly fluorescent probes for tumor imaging, which leverage the advantage of efficient penetrability and satisfactory accumulation, have attracted much attention. In this work, we rationally integrate charge switchable azobenzene moiety and long wavelength aggregation-induced emission fluorogens (AIEgens) into one water-soluble polymer to construct the hypoxia-triggered in situ self-assembly fluorescent probe for tumor imaging. Due to the good water solubility and the quenching effect of azobenzene moiety, the AIEgens containing polymer showed no significant fluorescence. Under a tumor hypoxic environment, the enzymatic reduction of azobenzene triggered cationic quaternary ammonium converting into anionic carboxylate. Then self-assembly nanoparticles were obtained, driven by the electrostatic interaction between negatively charged carboxylate ion and positively charged AIEgens, which emitted a strong orange-red fluorescence.
近年来，用于肿瘤成像的刺激响应型原位自组装荧光探针利用了高效穿透性和良好富集性的优势，备受关注。在本研究中，我们将电荷可切换的偶氮苯部分与长波长聚集诱导发光荧光团（AIEgens）合理整合到一种水溶性聚合物中，构建了用于肿瘤成像的缺氧触发原位自组装荧光探针。由于良好的水溶性和偶氮苯部分的猝灭作用，含AIEgens的聚合物无明显荧光。在肿瘤缺氧环境下，偶氮苯的酶促还原触发阳离子季铵转化为阴离子羧酸盐。然后，在带负电荷的羧酸根离子与带正电荷的AIEgens之间的静电相互作用驱动下，形成自组装纳米颗粒，发出强烈的橙红色荧光。
