Versatile molybdenum disulfide based antibacterial composites for in vitro enhanced sterilization and in vivo focal infection therapy

Abstract

Biologically, MoS2-based nanostructures have been intensely applied for the photothermal therapy of cancer, but rarely for antibacterial uses. In this contribution, a multifunctional chitosan (CS) functionalized magnetic MoS2 (abbreviated to CFM) was constructed to nonspecifically combat bacterial infection by integrating bacterial conjugation and enrichment, and NIR-triggered photothermal sterilization. Owing to the abundant introduced amino groups, the CFM complex offers a significantly enhanced conjugation efficiency without obvious specificity towards both Gram-positive and -negative bacteria compared to amino-free magnetic MoS2. The magnetic properties of CFM obtained from iron oxide facilitate the enrichment of a CFM-bacteria conjugate, improving the photothermal efficiency of CFM as a photothermal antibacterial agent. Specifically, after being trapped together with bacteria cells, CFM shows an enhanced in vitro photothermal sterilization ability. In vivo S. aureus-induced abscess treatment studies show faster healing when CFM is used as subcutaneous nano-localized heating sources with the assistance of an external magnet to concentrate the CFM-bacteria conjugate. This work establishes an innovative solution and a novel antimicrobial agent for combating bacterial infections without the use of antibiotics, which may open a new area of application and research for MoS2-based nanostructures.

Recent Progress in Two‐Dimensional Antimicrobial Nanomaterials

“…MoS 2 is another important building scaffold for photothermal‐based antibacterial nanomaterials. A multifunctional CFM nanocomposite with NIR absorbance has been fabricated . After binding to bacteria, the CFM nanocomposite can effectively damage the integrity of the bacterial cell membrane with NIR‐triggered hyperthermia.…”

“…After binding to bacteria, the CFM nanocomposite can effectively damage the integrity of the bacterial cell membrane with NIR‐triggered hyperthermia. The CFM nanocomposite exhibits a higher binding ability towards Gram‐positive bacteria than that to Gram‐negative bacteria (Figure B) . It is possible that the highly negatively charged membrane of Gram‐positive bacteria favors more powerful nonspecific electrostatic interactions with the material .…”

“…Fe 3 O 4 ‐functionalized, water‐dispersible, MoS 2 antibacterial nanocomposites were synthesized. Magnetic enrichment by Fe 3 O 4 NPs can improve the photothermal conversion efficiency of MoS 2 , which consequently improves the antibacterial performance . Similarly, PEG‐functionalized MoS 2 (PEG–MoS 2 ) was prepared through a one‐pot hydrothermal method.…”

Design, Synthesis, and Surface Modification of Materials Based on Transition‐Metal Dichalcogenides for Biomedical Applications

“…In addition to using one‐pot synthesis methods, multistep methods can also be employed to prepare TMDC nanocomposites with greatly improved performance. For example, many TMDC nanocomposites, such as MoS 2 /Fe 3 O 4 , WS 2 @Fe 3 O 4 , and iron‐oxide‐coated MoS 2 nanocomposites, have been prepared by multistep methods. TMDC nanoflakes have an advantage of efficient molecular binding and drug loading, as well as strong NIR and X‐ray absorbance, while Fe 3 O 4 possesses a good magnetic targeting ability.…”

“…In addition, to render TMDCs with hydrophilic properties, surface modification can also exert a great impact on their biological performance, such as improved cellular uptake and biodistribution and prolonged circulation time in the blood, as well as stabilized performance in a complex biomedium (e.g., plasma or cellular binding receptors) . Due to their large surface‐to‐volume ratio, it is easy to integrate TMDCs with other functional components to enrich their characteristics for various biomedical purposes, such as drug delivery, synergistic therapy, multimodal imaging, or highly sensitive biosensing . Such a large surface area also affords maximal interaction with the targeting site, so as to increase diagnostic sensitivity as well as therapeutic efficiency.…”