A CuS@g-C₃N₄ heterojunction endows scaffold with synergetic antibacterial effect

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Graphitic carbon nitride (g-C3N4) shows promise for photodynamic antibacterial therapy but suffers from rapid electron-hole recombination and biofilm formation.
• These limitations hinder its effectiveness in combating bacterial infections.

Purpose of the Study:

• To synthesize a CuS@g-C3N4 nanoheterojunction to overcome the limitations of g-C3N4 for enhanced photodynamic antibacterial therapy.
• To integrate the nanoheterojunction into a poly-l-lactide (PLLA) scaffold for potential biomedical applications.

Main Methods:

• In-situ growth of copper sulfide (CuS) nanoparticles onto g-C3N4 to form CuS@g-C3N4 nanoheterojunctions.
• Incorporation of CuS@g-C3N4 nanoparticles into PLLA scaffolds.
• Photoelectrochemical analysis to assess charge separation efficiency.
• Thermal imaging to evaluate photothermal properties.
• Antibacterial assays against E. coli and S. aureus.

Main Results:

• The CuS@g-C3N4 nanoheterojunction significantly improved electron-hole separation, leading to a sevenfold increase in reactive oxygen species (ROS) production.
• The PLLA scaffold exhibited a strong photothermal effect, effectively disrupting bacterial biofilms by degrading extracellular DNA.
• The combined ROS generation and photothermal disruption resulted in high antibacterial rates of 97.2% against E. coli and 98.5% against S. aureus.

Conclusions:

• The developed CuS@g-C3N4 nanoheterojunction effectively enhances photodynamic antibacterial therapy by improving charge separation and leveraging photothermal effects.
• The PLLA scaffold incorporating this nanoheterojunction demonstrates significant potential for combating bacterial infections and preventing biofilm formation.