Zhu Xueyi, Ma Ning, Wan Yizhen, Wang Lu, Zhang Yu, Yan Chengyu, Qian Weiping
State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
Analyst. 2023 Feb 27;148(5):1024-1031. doi: 10.1039/d2an02079c.
Immobilizing ligands is a crucial part of preparing optical sensors and directly connected to the sensitivity, stability, and other characteristics of sensors. In this work, an ordered porous layer interferometry (OPLI) system that can monitor the covalent coupling process of ligands in real time was developed. Films of silica colloidal crystal (SCC), as optical interference substrates, were surface modified by three different reagents: chloroacetic acid, glutaric anhydride, and carboxymethyl dextran. protein A (SPA), the ligand, was immobilized on SCC films. The covalent coupling process of SPA and SCC films can be dynamically monitored by the OPLI system. In addition, the three different strategies were evaluated by comparing the efficiency of the sensors prepared by different methods for binding Immunoglobulin G (IgG). The glutaric anhydride-modified sensor offers apparent advantages in terms of bound IgG quantity and affinity. This system provides a simple and intuitive way to determine the efficiency of different covalent coupling strategies. Furthermore, the sensor covalently coupled with SPA also excels in the determination of IgG content in complex systems such as milk. At the same time, the covalent coupling gives the sensor the ability to be stored stably over time.
固定化配体是制备光学传感器的关键部分，并且与传感器的灵敏度、稳定性及其他特性直接相关。在这项工作中，开发了一种能够实时监测配体共价偶联过程的有序多孔层干涉术（OPLI）系统。作为光学干涉基底的二氧化硅胶体晶体（SCC）薄膜，通过三种不同的试剂进行表面改性：氯乙酸、戊二酸酐和羧甲基葡聚糖。将配体蛋白A（SPA）固定在SCC薄膜上。OPLI系统可以动态监测SPA与SCC薄膜的共价偶联过程。此外，通过比较不同方法制备的传感器结合免疫球蛋白G（IgG）的效率，对这三种不同策略进行了评估。戊二酸酐改性的传感器在结合IgG的量和亲和力方面具有明显优势。该系统提供了一种简单直观的方法来确定不同共价偶联策略的效率。此外，与SPA共价偶联的传感器在测定牛奶等复杂体系中的IgG含量方面也表现出色。同时，共价偶联使传感器能够随时间稳定储存。
