Chang_2025_Small.Methods__e01470

Organophosphorus (OP) nerve agents cause neurotoxicity through irreversible inhibition of acetylcholinesterase (AChE), while conventional therapeutic strategies are inadequate to fully restore cholinergic function. Artificial enzymes with AChE-like activity are urgently needed to provide sustainable catalytic capacity to address this limitation. Guided by the acid-base synergistic catalytic mechanism of the ester hydrolysis reaction, the 29-ZIF-8/SA composite with excellent AChE-like activity is successfully constructed by a defect engineering strategy with sodium alginate (SA) as a modulator. The mechanistic studies demonstrate that the basic site -OH groups introduced by SA, combined with the Lewis acid sites Zn(2+) of ZIF-8, acted synergistically to form a bifunctional catalytic active site that enhances hydrolytic activity. Meanwhile, SA mediates the rapid formation of mesoporous architectures, improving substrate accessibility and mass transfer efficiency. In addition, 29-ZIF-8/SA demonstrates excellent environmental stability under harsh conditions and resists the inhibitory effect of methyl parathion (MP) on AChE activity. In vitro and in vivo experiments show that the 29-ZIF-8/SA composite exhibits cytoprotective properties to effectively attenuate MP-induced neurotoxicity. This work not only presents a designable method for the construction of highly active hydrolases, which are rarely reported, but also offers a new approach for nanozymes-based treatment of acute OP poisoning.