Bio-inspired nanozyme: a hydratase mimic in a zeolitic imidazolate framework. Issue 13 (19th March 2019)

• Record Type: Journal Article
• Authors: Chen, Jinxing; Huang, Liang; Wang, Qingqing; Wu, Weiwei; Zhang, He; Fang, Youxing; Dong, Shaojun
• Is Part Of: Nanoscale. Volume 11:Issue 13(2019)
• Page Start: 5960
• Page End: 5966
• Publication Date: 2019-03-19
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c9nr01093a
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : ZIF-8 possesses intrinsic CA-like activity and exhibits promiscuous esterase and acetylcholinesterase activities. The enzymatic activities of ZIF-8 are attributed to the bionic constituent units. Abstract : Nanozymes provide comparative advantages over natural enzymes and conventional artificial enzymes for catalytic reactions. However, nanozymes are only suitable for limited types of reactions, whose catalytic principles are not yet fully revealed. Herein, a new nanozyme based on a bionic zeolitic imidazolate framework is proposed. Zeolitic imidazolate framework-8 (ZIF-8) possesses a similar geometric structure to that of the active center of human carbonic anhydrase II (hCAII) and exhibits catalytic performance analogous to that of the hCAII. The less imidazolate coordinated zinc cations on the external surface of ZIF-8 can act as Lewis acid sites, lowering the p K a of Zn-bound H2 O molecules from 14 to 8.4, which facilitates the deprotonation of H2 O molecules and generation of zinc-bound hydroxide nucleophiles. The esterase-like ZIF-8 nanozyme shows a similar affinity to p -nitrophenyl acetate compared with hCAII. The ZIF-8 nanozyme also promotes CO2 hydration and acetylthiocholine hydrolysis reaction, and a series of ZIFs are also found with intrinsic enzyme-like activities due to similar compositions and spatial structures. These results imply that the bionic nanoparticles can be developed to fabricate a new generation of nanozymes by mimicking the active sites of natural enzymes.