He Xiaolong, Wang Beibei, Li Xuefeng, Dong Jinfeng
Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University Wuhan 430072 P. R. China
RSC Adv. 2019 Sep 6;9(48):28102-28111. doi: 10.1039/c9ra05997k. eCollection 2019 Sep 3.
Herein, a new family of aggregation-induced emission (AIE) amphiphilic copolymers, named poly(-(2-methacryloyloxyethyl)pyrrolidone)--poly(lauryl methacrylate--1-ethenyl-4-(1,2,2-triphenylethenyl)benzene), PNMP --P(LMA --TPE ), was developed by the reversible addition-fragmentation chain transfer (RAFT) polymerization method. The polymerization degree of the NMP segment was kept constant at 35, whereas that of the LMA segment ranged from 9 to 55 with the polymerization degree ratio / of the LMA and TPE segments being around 9. As a result, the PNMP --P(LMA --TPE ) copolymer gradually transformed from being water soluble to oil soluble with an increase in the length of the P(LMA --TPE ) segment. Moreover, these copolymers could form self-organized normal and reverse assemblies in both water and -dodecane. Various morphologies, including spherical micelles, worm-like micelles and vesicles, were confirmed by the transmission electron microscopy (TEM) observation. Specifically, the micelle-to-vesicle transition worm-like micelles occurred in the aqueous solution upon increasing the length of the P(LMA --TPE ) segment, whereas the reverse transition occurred in -dodecane. Because of the presence of the AIE-active TPE segment, both the aqueous and the -dodecane solutions of PNMP --P(LMA --TPE ) were highly luminescent, and their fluorescence quantum yields significantly depended on the polarity of the solvent and the morphology of the assemblies. Due to the strong luminescence properties of PNMP --P(LMA --TPE ) assemblies, these AIE-active amphiphilic copolymers acted as excellent bioimaging probes with high efficiency.
在此，通过可逆加成-断裂链转移（RAFT）聚合法开发了一种新型的聚集诱导发光（AIE）两亲共聚物，命名为聚（-（2-甲基丙烯酰氧基乙基）吡咯烷酮）-聚（甲基丙烯酸月桂酯-1-乙烯基-4-（1,2,2-三苯乙烯基）苯），PNMP - P（LMA - TPE）。NMP链段的聚合度保持恒定为35，而LMA链段的聚合度范围为9至55，LMA和TPE链段的聚合度比/约为9。结果，随着P（LMA - TPE）链段长度的增加，PNMP - P（LMA - TPE）共聚物逐渐从水溶性转变为油溶性。此外，这些共聚物可以在水和正十二烷中形成自组装的正相和反相聚集体。通过透射电子显微镜（TEM）观察证实了包括球形胶束、蠕虫状胶束和囊泡在内的各种形态。具体而言，随着P（LMA - TPE）链段长度的增加，在水溶液中发生了胶束到囊泡的转变以及蠕虫状胶束的形成，而在正十二烷中发生了相反的转变。由于存在AIE活性的TPE链段，PNMP - P（LMA - TPE）的水溶液和正十二烷溶液都具有很强的发光性，并且它们的荧光量子产率显著取决于溶剂的极性和聚集体的形态。由于PNMP - P（LMA - TPE）聚集体具有很强的发光特性，这些AIE活性两亲共聚物作为高效的生物成像探针发挥了出色的作用。
