A NIR‐light‐driven Black Phosphorus Based Nanocomposite for Combating Bacteria

Abstract

Nanocomposites of semiconducting two‐dimensional (2D) materials provide advantageous for combating bacterial infections to overcome antibiotic resistance. In this study, the nanocomposites of 2D black phoshorus (BP) and silver nanoparticles (NPs) were prepared by anchoring as‐synthesized Ag NPs on few‐layer BP nanosheets via liquid self‐assembly method and used as a NIR‐light‐driven antibacterial agent against Gram‐negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and Gram‐positive bacteria (Enterococcus faecalis and Bacillus cereus). The BP/Ag nanocomposites showed excellent photothermal effect and oxidative stress ability to inhibit the initial logarithmic growth phase of E. faecalis and B. cereus. According to the bacterial growth curve, agar plate assay and live/dead viability test, as‐synthesized BP/Ag nanocomposites were found to be more effective antibacterial agent for Gram‐positive bacteria than Gram‐negative bacteria. The presented NIR‐light‐driven BP‐based nanoplatform can open a new avenue for avoiding bacterial resistance and combating pathogenic bacteria and also broad‐spectrum disinfection applications.

The Effects of Black Phosphorus‐Based Composites on Foodborne Pathogen Growth and Biofilm

“…The TEM image in Figure 1c reveals two distinct size ranges of Ag NPs, with an average particle size ranging from 4 to 9 nm. The as‐synthesized Au and Ag NPs were then successfully anchored onto the FLBP using a liquid‐phase self‐assembly technique [29] . resulting in the formation of BP/Au and BP/Ag nanocomposites.…”

“…Pristine BP nanosheets, BP/Ag and BP/Au nanocomposites were synthesized and fully characterized by our group as previously described. [11,29] Initially, bulk BP crystals were synthesized by using the vapor transport method and later transformed into few-layer black phosphorus (FLBP) through the ultrasoundassisted exfoliation in deoxygenated water. Transmision electron microscopy (TEM) images of pristine BP in Figure 1a revealed that the resulting dispersion possesses a thin layered 2D structure.…”

“…However, the growth inhibition was increased with NIR illumination, probably because of the photothermal and/or ROS generation, which could suppress bacterial growth, as previously reported. [11,29] Figure 2a,c indicates that the antibacterial effects of BP/Ag nanocomposites against both B. cereus and S. enteritidis were higher than that of bare BP nanosheets. Our prior study showed a plausible pathway which is the excited electrons on conduction band (CB) of BP nanosheets are transported to the d-band level of Ag NPs through Schottky junction.…”

“…Our prior study showed a plausible pathway which is the excited electrons on conduction band (CB) of BP nanosheets are transported to the d-band level of Ag NPs through Schottky junction. [29] The accumulated electron on Ag NPs creates ROS from molecular oxygen, thus antibacterial activity could be enhanced by the anchoring Ag NPs on BP nanosheets. As shown in Figure 2b,d, similar to BP/Ag, BP/Au nanocomposites had more antibacterial effect than that of free BP nanosheets against B. cereus and S. enteritidis.…”

“…The authors have cited additional references within the Supporting Information. [11,12,29,[49][50][51] Supporting Information includes bacterial growth curves at different concentrations of…”