Qilu University of Technology (Shandong Academy of Sciences), Shandong Analysis and Test Center, Jinan, 250014, China; School of Pharmaceutical Sciences, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, China.
Qilu University of Technology (Shandong Academy of Sciences), Shandong Analysis and Test Center, Jinan, 250014, China; Department of General Surgery, The First Afffliated Hospital of Shandong First Medical University, Jinan, 250014, China.
Biosens Bioelectron. 2023 Apr 1;225:115112. doi: 10.1016/j.bios.2023.115112. Epub 2023 Jan 28.
Gel-sol transition-based biosensors are a promising and popular alternative for portable, cost-effective, and user-friendly point-of-care testing (POCT). However, the improvement of sensitivity and practicability is highly demanded. In this work, a Fe-NC single-atom catalyst (SAC) is successfully synthesized and used as a signal amplification element for highly sensitive gel-sol transition-based biosensing. The Fe-NC SAC owns excellent peroxidase-like activity of 188 U/mg due to its definite atomically active centers and maximum atomic utilization of active metal atoms. As a proof-of-concept, the Fe-NC SAC is uniformly encapsulated in gelatin hydrogel to obtain a hydrogel sensor that allows colorimetric detection of trypsin based on gel-sol transition. The gelatin hydrogel network collapses derived from the hydrolysis by trypsin, and thereby the released Fe-NC SAC leads to the colorimetric sensing process. The designed hydrogel sensor offers a low detection limit of 1 ng/mL with a range from 1 to 100 ng/mL toward trypsin detection, exhibiting excellent selectivity and sensitivity, and well-performed practical detection in human serum. This work offers a successful paradigm for designing a promising SACs-related detection strategy and paves a new way to develop high-performance gel-sol transition-based sensors and various POCT applications.
基于凝胶-溶胶转变的生物传感器是一种有前途且受欢迎的替代方案，适用于便携式、经济实惠且用户友好的即时检测（POCT）。然而，人们强烈需要提高其灵敏度和实用性。在这项工作中，成功合成了一种 Fe-NC 单原子催化剂（SAC），并将其用作基于凝胶-溶胶转变的高灵敏度生物传感的信号放大元件。由于其确定的原子活性中心和最大的活性金属原子原子利用率，Fe-NC SAC 具有出色的过氧化物酶样活性，为 188 U/mg。作为概念验证，将 Fe-NC SAC 均匀包裹在明胶水凝胶中，得到一种水凝胶传感器，可基于凝胶-溶胶转变进行胰蛋白酶的比色检测。明胶水凝胶网络由于胰蛋白酶的水解而崩溃，从而释放出 Fe-NC SAC，从而引发比色传感过程。设计的水凝胶传感器对胰蛋白酶的检测具有低至 1 ng/mL 的检测限，检测范围为 1 至 100 ng/mL，具有出色的选择性和灵敏度，在人血清中的实际检测效果良好。这项工作为设计有前途的 SAC 相关检测策略提供了一个成功范例，并为开发高性能凝胶-溶胶转变传感器和各种 POCT 应用开辟了新途径。
