MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
Analyst. 2011 Jun 7;136(11):2315-21. doi: 10.1039/c0an00813c. Epub 2011 Apr 14.
Herein, BSA-tetraphenylethene derivative conjugates with aggregation-induced emission (AIE) properties were constructed and used as fluorescent probes for label-free detection of protease and α1-antitrypsin. Conjugated AIE probes were formed based on the electrostatic induced assembly between an ammonium cation of quaternized tetraphenylethene salt and carboxyl anion groups of BSA. While water soluble quaternized tetraphenylethene salt showed very low fluorescence in its well-dispersed state, obvious enhancement in the fluorescence of the aggregated tetraphenylethene derivative on the BSA templates was achieved due to the abnormal aggregation-induced emission properties of tetraphenylethene. These BSA-tetraphenylethene derivative conjugates enabled label-free detection of protease. In the presence of trypsin, the BSA templates were enzymatically hydrolyzed and the conjugates decomposed. Therefore the quaternized tetraphenylethene molecules became increasingly isolated from each other. Accordingly, the aggregation to dispersing state change of tetraphenylethene derivative resulted in an obvious decrease in the fluorescence of the conjugates probes and enabled the sensitive and selective detection of trypsin. Furthermore, upon addition of α1-antitrypsin, the enzymatic activity of trypsin was inhibited and the fluorescence was consequently preserved. Sensitive detection of α1-antitrypsin was thus realised. The protein-tetraphenylethene derivative conjugates with aggregation-induced emission properties therefore show great promise for the monitoring of biological processes and cancer diagnostics with simplicity, high sensitivity, and rapid response.
本文构建了具有聚集诱导发光 (AIE) 性质的 BSA-四苯乙烯衍生物缀合物，并将其用作无标记检测蛋白酶和 α1-抗胰蛋白酶的荧光探针。缀合的 AIE 探针是基于季铵化四苯乙烯盐的铵阳离子与 BSA 的羧基阴离子之间的静电诱导组装形成的。虽然水溶性季铵化四苯乙烯盐在其良好分散状态下显示出非常低的荧光，但由于四苯乙烯的异常聚集诱导发光性质，聚集的四苯乙烯衍生物在 BSA 模板上的荧光得到明显增强。这些 BSA-四苯乙烯衍生物缀合物能够无标记检测蛋白酶。在存在胰蛋白酶的情况下，BSA 模板被酶解，缀合物分解。因此，季铵化四苯乙烯分子彼此之间变得越来越孤立。相应地，四苯乙烯衍生物的聚集到分散状态的变化导致缀合物探针的荧光明显降低，从而能够对胰蛋白酶进行灵敏和选择性检测。此外，加入α1-抗胰蛋白酶后，胰蛋白酶的酶活性被抑制，荧光得以保留。因此实现了对α1-抗胰蛋白酶的灵敏检测。具有聚集诱导发光性质的蛋白质-四苯乙烯衍生物缀合物因此具有简单、高灵敏度和快速响应的优点，有望用于监测生物过程和癌症诊断。
