Photoactive MOF-Derived Bimetallic Silver and Cobalt Nanocomposite with Enhanced Antibacterial Activity

Abstract

Conventional antibiotic-based treatment of bacterial infections remains one of the most difficult challenges in medicine because of the threat of multidrug resistance caused by indiscriminate abuse. To solve these problems, it is essential to develop an effective antibacterial agent that can be used at a small dose while minimizing the occurrence of multiple resistance. Metal–organic frameworks (MOFs), which are hyper-porous hybrid materials containing metal ions linked by organic ligands, have recently attracted attention because of their strong antibacterial activity through metal-ion release, unlike conventional antibiotics. In this study, we developed a photoactive MOF-derived cobalt–silver bimetallic nanocomposite (Ag@CoMOF) by simply depositing silver nanoparticles on a cobalt-based MOF through nanoscale galvanic replacement. The nanocomposite structure continuously releases antibacterial metal ions (i.e., Ag and Co ions) in the aqueous phase and exhibits a strong photothermal conversion effect of Ag nanoparticles, accompanied by a rapid temperature increase of 25–80 °C under near-infrared (NIR) irradiation. Using this MOF-based bimetallic nanocomposite, superior antibacterial activities were achieved by 22.1-fold for Escherichia coli and 18.3-fold for Bacillus subtilis enhanced inhibition of bacterial growth in a liquid culture environment compared with the generally used chemical antibiotics. In addition, we confirmed the synergistic enhancement of the antibacterial ability of the bimetallic nanocomposite induced by NIR-triggered photothermal heating and bacterial membrane disruption even when using a small amount of the nanocomposites. We envision that this novel antibacterial agent using MOF-based nanostructures will replace traditional antibiotics to circumvent multidrug resistance and present a new approach to antibiotic development.

Efficient visible-light-driven photocatalytic removal of Acid Blue 92, E. coli, and S. aureus over Ag-AgCl nanoparticles-decorated bismuth sulfide microparticles

“…As shown in figure 12, the cell walls of both gram-negative and grampositive bacteria were seriously damaged with the photocatalytic treatment. During the reaction time, reactive oxygen species, predominantly superoxide anion radicals, are generated in the medium, which efficiently attacks the outer shell of the bacterial cell wall and degrades it [59]. Due to the thicker and more tenacious cell wall structure, gram-positive bacteria indicate more persistency against such attacks, and the rate of photoinactivation is lower for these organisms, as revealed in figure 11.…”

Supramolecular Structure of the β-Cyclodextrin Metal–Organic Framework Optimizes Iodine Stability and Its Co-delivery with l-Menthol for Antibacterial Applications

“…Iodine (I 2 ) exhibits both antibacterial and virucidal activities and reduces the risk of bacterial resistance. I 2 can be used for sterilization by disrupting bacterial cell walls and protein structures. − As for virus inactivation, I 2 solution can rapidly inactivate SARS-CoV-2 in a brief contact time. , The antiviral effect of I 2 is directly related to its content . Moreover, I 2 administration in the URT is deemed to be relatively safe.…”

SiO2@AuAg/PDA hybrid nanospheres with photo-thermally enhanced synergistic antibacterial and catalytic activity

“…30 Kim found that Ag nanoparticles in cobalt-silver bimetallic nanocomposites exhibited strong photothermal conversion efficiency, which synergized with Ag and Co ions to achieve a signicant antimicrobial effect. 31 Although Ag + is effective in killing bacteria as a broad-spectrum antimicrobial agent, the severe biotoxicity also limits its application. Therefore, a bio-safe nanoplatform that not only balances the biocompatibility and toxicity but also possesses controllable photothermal antibacterial behavior is highly required.…”