Mn-Etched Zeolitic Imidazolate Framework-67 Nanostructures for Biomimetic Superoxide Anion Sensing

作者：Fang Shi, Zhuanzhuan Shi, Zhuo Zou, Xiaoshuai Wu, Zhengyang Liu, Liang Liu, Qianqian Fu, Yuan Li, Wei Sun, Chunxian Guo, Chang Ming Li · 发表于：ACS Applied Nano Materials · 年份：2022 · DOI：10.1021/acsanm.2c00295 · 被引用次数：19 · 研究领域：Advanced Nanomaterials in Catalysis、Electrochemical sensors and biosensors、Advanced biosensing and bioanalysis techniques

It is a great challenge to detect superoxide anions (O 2 •– ) with low level concentrations and short half-life in biological systems. Herein, mild and facile Mn etching for zeolitic imidazolate framework-67 (ZIF-67) was used to synthesize Mn/ZIF-67 with a hydrangea-like nanostructure for biomimetic sensing of O 2 •– released from living cells. The tailored optimal Mn/ZIF-67 sensor achieves a high selectivity, a fast response time (1.6 s), a broad linear detection range (1.5 nM–10 μM), an ultralow detection limit (0.8 nM), and a remarkably high sensitivity (439.2 μA μM –1 cm –2 ) that ranks the best among all reported conventional Mn- and Co-compound-based nanozymes such as Co 2 P and Mn 3 (PO 4 ) 2 . The excellent sensing performances are attributed to the Mn etching-generating hydrangea-like nanostructure for a significantly increased reaction surface area and coordinating Mn 2+ with Co 2+ to raise the oxidation state of Co 2+ for fast electron transfer during the oxidation of O 2 •– . This work holds great potential for a highly sensitive O 2 •– nanozyme sensor in practical clinical diagnosis and bioscience research, while shedding fundamental light on designs of sensitive nanozyme sensors by incorporating two metal ions with largely different negativity for an efficient electrocatalytic process, thereby possessing universal significance.