Nanoarchitectonics of Bimetallic Cu-/Co-Doped Nitrogen-Carbon Nanozyme-Functionalized Hydrogel with NIR-Responsive Phototherapy for Synergistic Mitigation of Drug-Resistant Bacterial Infections.

Superbug infections and transmission have become major challenges in the contemporary medical field. The development of novel antibacterial strategies to efficiently treat bacterial infections and conquer the problem of antimicrobial resistance (AMR) is extremely important. In this paper, a bimetallic CuCo-doped nitrogen-carbon nanozyme-functionalized hydrogel (CuCo/NC-HG) has been successfully constructed. It exhibits photoresponsive-enhanced enzymatic effects under near-infrared (NIR) irradiation (808 nm) with strong peroxidase (POD)-like and oxidase (OXD)-like activities. Upon NIR irradiation, CuCo/NC-HG possesses photodynamic activity for producing singlet oxygen(1O2), and it also has a high photothermal conversion effect, which not only facilitates the elimination of bacteria but also improves the efficiency of reactive oxygen species (ROS) production and accelerates the consumption of GSH. CuCo/NC-HG shows a lower hemolytic rate and better cytocompatibility than CuCo/NC and possesses a positive charge and macroporous skeleton for restricting negatively charged bacteria in the range of ROS destruction, strengthening the antibacterial efficiency. Comparatively, CuCo/NC and CuCo/NC-HG have stronger bactericidal ability against methicillin-resistant Staphylococcus aureus (MRSA) and ampicillin-resistant Escherichia coli (AmprE. coli) through destroying the cell membranes with a negligible occurrence of AMR. More importantly, CuCo/NC-HG plus NIR irradiation can exhibit satisfactory bactericidal performance in the absence of H2O2, avoiding the toxicity from high-concentration H2O2. In vivo evaluation has been conducted using a mouse wound infection model and histological analyses, and the results show that CuCo/NC-HG upon NIR irradiation can efficiently suppress bacterial infections and promote wound healing, without causing inflammation and tissue adhesions.

Cu2+@metal-organic framework-derived amphiphilic sandwich catalysts for enhanced hydrogenation selectivity of ketenes at the oil-water interface.

Selective catalysis has always been an essential process for manufacturing various fine chemicals, such as food additives, pharmaceuticals and perfumes. Practically, pure target products are difficult to obtain even after complex purification procedures during industrial production. The development of a cost-effective, highly chemoselective and long-life catalyst may be an attractive solution, but such a catalyst is elusive. Herein, a novel class of amphiphilic N-doped carbon (NC), featuring graphitic carbon (GC) and highly dispersed Cu@Co NPs, was fabricated via simple calcination of a Cu2+-doped bimetallic metal-organic framework (MOF) precusor directly. Compared with monometallic Co@GC/NC, the side reaction of CO bond hydrogenation is obviously restrained, and thus, pure target product can be systematically obtained by Cu@Co@GC/NC, highlighting the high selectivity of Cu. More importantly, an amphiphilic characteristic in Cu@Co@GC/NC is a significant knob to integrate organic substrates with water very well. This amphiphilic material shows great potential as a field-deployable pathway for dispersible metal catalysts in organic systems.

Photocatalytic cascade reactions and dye degradation over CdS-metal-organic framework hybrids.

Two bifunctional CdS-MOF composites have been designed and fabricated. The hybrids exhibited synergistic photocatalytic performance toward two cascade reactions under visible light integrating photooxidation activity of CdS and Lewis acids/bases of the MOF. The composite further promoted the photodegradation of dyes benefiting from effective electron transfer between the MOF and CdS.