Key Laboratory for Advanced Materials, Shanghai Key Laboratory of Functional Materials Chemistry, Joint International Laboratory for Precision Chemistry, Frontiers Science Center for Materiobiology & Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, P. R. China.
Department of Chemistry, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt.
Anal Chem. 2022 Oct 18;94(41):14280-14289. doi: 10.1021/acs.analchem.2c02814. Epub 2022 Oct 6.
The redox homeostasis in living cells is greatly crucial for maintaining the redox biological function, whereas accurate and dynamic detection of intracellular redox states still remains challenging. Herein, a reversible surface-enhanced Raman scattering (SERS) nanosensor based on covalent organic frameworks (COFs) was prepared to dynamically monitor the redox processes in living cells. The nanosensor was fabricated by modifying the redox-responsive Raman reporter molecule, 2-Mercaptobenzoquione (2-MBQ), on the surface of gold nanoparticles (AuNPs), followed by the in situ coating of COFs shell. 2-MBQ molecules can repeatedly and quickly undergo reduction and oxidation when successively treated with ascorbic acid (AA) and hypochlorite (ClO) (as models of reductive and oxidative species, respectively), which resulted in the reciprocating changes of SERS spectra at 900 cm. The construction of the COFs shell provided the nanosensor with great stability and anti-interference capability, thus reliably visualizing the dynamics of intracellular redox species like AA and ClO by SERS nanosensor. Taken together, the proposed SERS strategy opens up the prospects to investigate the signal transduction pathways and pathological processes related with redox dynamics.
活细胞中的氧化还原平衡对维持氧化还原生物功能至关重要，然而，精确和动态地检测细胞内的氧化还原状态仍然具有挑战性。在此，我们制备了一种基于共价有机框架（COFs）的可逆表面增强拉曼散射（SERS）纳米传感器，以动态监测活细胞中的氧化还原过程。该纳米传感器是通过将氧化还原响应性拉曼报告分子 2-巯基苯并喹啉（2-MBQ）修饰在金纳米粒子（AuNPs）表面，然后原位包覆 COFs 壳层而制备的。当 2-MBQ 分子分别与抗坏血酸（AA）和次氯酸根（ClO）（分别作为还原性和氧化性物质的模型）连续处理时，2-MBQ 分子可以反复且快速地经历还原和氧化，这导致在 900cm 处的 SERS 光谱发生往复变化。COFs 壳层的构建为纳米传感器提供了极好的稳定性和抗干扰能力，从而可以通过 SERS 纳米传感器可靠地可视化 AA 和 ClO 等细胞内氧化还原物质的动力学。总之，所提出的 SERS 策略为研究与氧化还原动力学相关的信号转导途径和病理过程开辟了前景。
