Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Shida Road 1#, Nanchong 637009, China.
Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Shida Road 1#, Nanchong 637009, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Mar 5;268:120653. doi: 10.1016/j.saa.2021.120653. Epub 2021 Nov 22.
In this work, a bifunctional peptide-based fluorescent probe L containing a tetrapeptide scaffold (Pro-Gly-His-Trp-NH) and a dansyl group was synthesized using solid phase peptide synthesis (SPPS) technology. As designed, L, based on a FRET mechanism, exhibited high selectivity, excellent ratiometric signals, and fast response to Zn in aqueous solutions at an excitation wavelength of 280 nm. In addition, when excited at 320 nm, L exhibited a fluorescent "turn-on" response towards Zn based on PET mechanism. More importantly, the stoichiometry of L and Zn was determined to be 2:1 by fluorescent titration, Job's plot method, and ESI-MS spectrometry. The association constant for Zn ions was determined to be 6.26 × 10 M, while the limit of detection (LOD) of L was estimated as 5.43 nM, which is a much lower value than WHO and EPA guidelines for drinking water. Moreover, L was successfully applied to detect both Zn and Cu in living cells due to good biocompatibility and excellent low toxicity.
在这项工作中，我们使用固相肽合成（SPPS）技术合成了一种基于四肽骨架（Pro-Gly-His-Trp-NH）和丹磺酰基的双功能肽基荧光探针 L。根据设计，L 基于 FRET 机制，在激发波长为 280nm 的水溶液中对 Zn 表现出高选择性、优异的比率信号和快速响应。此外，当在 320nm 激发时，L 基于 PET 机制对 Zn 表现出荧光“开启”响应。更重要的是，通过荧光滴定、Job 图法和 ESI-MS 光谱法确定了 L 与 Zn 的计量比为 2:1。Zn 离子的结合常数确定为 6.26×10 M，而 L 的检测限（LOD）估计为 5.43nM，远低于世界卫生组织和美国环保署饮用水标准。此外，由于良好的生物相容性和优异的低毒性，L 成功地应用于活细胞中 Zn 和 Cu 的检测。
