Antibacterial Performance of a Gold‐Loaded g‐C₃N₄ Nanocomposite System in Visible Light‐Dark Dual Mode

Abstract

Semiconductor photocatalysis technology, which can kill pathogenic microorganisms in a green and broad‐spectrum way, is a new research field with great application potential. Due to the dependence on light, semiconductor materials have the problems of low utilization rate of sunlight and inactivation under dark conditions. A simple Au‐loaded g‐C3N4 (Au/g‐C3N4) nanocomposites was studied. Under dark conditions, the antibacterial efficiency of 1.2 % Au/g‐C3N4 reached 99.1 % relative to 105 CFU (Colony‐FormingUnits)/mL E. coli. Under light conditions, the antibacterial efficiency of 0.9 % Au/g‐C3N4 reached 94.1 % relative to 107 CFU/mL E. coli. The influence of contact time, Au loading and bacterial concentration on its antibacterial performance under dark conditions was discussed in detail. Through photoelectrochemistry, SEM, TEM and reactive oxygen species (ROS) detection the microscopic charge behaviour was revealed in the system, and a light‐dark dual‐mode antibacterial mechanism was proposed.

Sensitive Electrochemical Sensor for Gallic Acid Determination in Honey Based on g-C3N4/AuNPs Modified Carbon Paste Electrode

“…1. 34,37 Fourier transform infrared spectroscopy.-An additional proof for the synthesis of the g-C 3 N 4 and g-C 3 N 4 /AuNPs is given by their FTIR spectra. Figure 2 show the FTIR spectra of g-C 3 N 4 and g-C 3 N 4 /AuNPs samples.…”

Polyvinyl alcohol/chitosan nanofiber membranes loaded with oxygenated graphitic carbon nitride nanosheets for enhanced photocatalytic bacteriostasis

“…The inhibition zone diameter was measured by irradiation with simulated sunlight at 20,000 LUX for 10 min and then incubated under D50 fluorescent light (400–780 nm) in a bacterial incubator at 37°C for 24 h. The measurement of the inhibition zone is based on the average diameter of the transparent area 30 . To further study the magnitude of antibacterial rate, the plate counting method 31 was employed, 0.5 mL of the above bacterial suspension (10 7 CFU mL −1 ) was placed in a centrifuge tube with a quantitative liquid medium and diluted to 10 5 CFU mL −1 , and the UV‐sterilized nanofiber membrane (1 × 1 cm) was placed in the centrifuge tube and incubated in an oscillating shaker incubator with light (D50 fluorescent light, 400–780 nm) for 1 h before taking 100 μL for plate coating, and counted after incubation at 37°C for 24 h. The experiments for antibacterial properties were performed in triplicate. The antibacterial rate of the samples was calculated according to Equation (). where Κ is the antibacterial rate, %.…”

Chemically amplified molecular resins for shrinkage-controlled direct nanoimprint lithography of functional oxides: an application towards dark-light dual-mode antibacterial surfaces

“…[45][46][47] Recently, a few literature have reported photocatalytically-active materials that exhibit antibacterial activity under dark-light dual mode. [48][49][50][51][52] Nevertheless, such materials fall under the category of powders and hence, the development of dual mode-active coatable compositions could be highly beneficial and attractive for rendering numerous frequently touched surfaces with antibacterial properties, especially in high-risk areas like hospitals and public places. 53,54 Therefore, as a potential application of the oxide nanoimprinting route employed here, we chose the popular photocatalyst TiO 2 to further create heterojunction with AgBr.…”