Optimization of Nanostructured Copper Sulfide to Achieve Enhanced Enzyme-Mimic Activities for Improving Anti-Infection Performance

Abstract

Advanced antibacterial methods are urgently needed to deal with possible infectious diseases. As promising alternatives to antibiotics, enzyme-mimic nanocatalysts face bottlenecks of low activities and indistinct catalytic mechanisms, which seriously restrict their development for anti-infection treatment. Herein, metastable copper sulfide (Cu 2-x S) nanozymes with diversiform sizes and compositions were selected to adjust the electronic structure for enhancing enzyme-mimic activities. The assynthesized large and thin nanoplates (L/TN nanoplates), with the stoichiometric ratio of Cu 1.25 S, were proven to possess the optimal peroxidase (POD)-mimic activity. Using quantum mechanics, it was theoretically revealed that the sulfur vacancies could alter the electronic structure of copper active sites and thus reduce the reaction energy barrier of H 2 O 2 to•OH to promote the PODmimic performance. Moreover, through enhanced enzyme-mimic activities, L/TN nanoplates achieved efficient depletion of glutathione and ascorbic acid for improving antibacterial performances. Further, synergizing with the NIR irradiation, the satisfactory destruction capability for bacteria and biofilm was achieved for L/TN nanoplates under an inflammatory level of hydrogen peroxide (50 μM). Altogether, this work provides a deeper understanding of geometrical and electronic properties-dependent antibacterial performance, and paves the way toward precise compositions and structures engineering of nanozymes.

Hyaluronic Acid-Based CuS Nanoenzyme Biodegradable Microneedles for Treating Deep Cutaneous Fungal Infection without Drug Resistance

“…Recently, nanoenzyme (NE) as special nanotechnology has attracted extensive attention in the field of antibacterial for its good stability, low production cost, and the ability to simulate the activity of natural enzymes . Especially, copper sulfide nanoenzyme (CuS NE) has good oxidase-like and peroxidase-like activities, , which can achieve effective antimicrobial activity and avoid drug resistance by producing reactive oxygen species (ROS). − However, the ROS produced by CuS NE has the defects of short half-life and difficult diffusion, which limits its application. Interestingly, PAF-26, as an antimicrobial peptide with only six amino acid residues, has good antifungal and cell-penetrating activities and is not easy to develop drug resistance. , More importantly, the ability of PAF-26 to penetrate cell envelope (cell wall and/or plasma membrane) , can facilitate CuS NE-generated ROS to enter fungi and overcome the defects of ROS.…”

Activity Regulating Strategies of Nanozymes for Biomedical Applications

“…Vacancy engineering is a competently approach to improve the inherent properties of the nanozymes catalytic activity, especially for regulating the electronic structure of the active site. [34] Chen and co-workers described MoS 2 nanozymes of both S vacancies (V S ) and Mo vacancies (V Mo ) with abundant active edge sites exposure. [35] The intermediates •OH desorbed on V Mo and V S lattice would be more accessible along with the larger exothermic process than MoS 2 and MoS 2 (V S ), thus leading to the enhanced catalytic activity of three types of enzymes (OXD-, POD-, and CAT-like).…”

Metal and Metal Oxide Nanomaterials for Fighting Planktonic Bacteria and Biofilms: A Review Emphasizing on Mechanistic Aspects

“…Otherwise, the surviving bacteria will form a new biofilm by choosing a suitable substrate to colonize again, causing a more serious infection [ 119 ]. Metal-based nanozymes catalyze the conversion of H 2 O 2 to the more toxic ROS through typical peroxidase-like reaction, which have attracted tremendous attention in antibiofilm therapy [ 120 , 121 , 122 ]. For example, Kumar et al eradicated biofilm using mixed FeCo-oxide-based surface-textured nanostructures with magnetocatalytic activity [ 116 ].…”