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Bacterial infection has traditionally been treated with antibiotics, but their overuse is leading to the development of antibiotic resistance. This may be mitigated by alternative approaches to prevent or treat bacterial infections without utilization of antibiotics. Among the alternatives is the use of photo-responsive antimicrobial nanoparticles and/or nanocomposites, which present unique properties activated by light. In this study, we explored the combined use of titanium oxide and polydopamine to create nanoparticles with photocatalytic and photothermal antibacterial properties triggered by visible or near-infrared light. Furthermore, as a proof-of-concept, these photo-responsive nanoparticles were combined with mussel-inspired catechol-modified hyaluronic acid hydrogels to form novel light-driven antibacterial nanocomposites. The materials were challenged with models of Gram-negative and Gram-positive bacteria. For visible light, the average percentage killed (PK) was 94.6 for E. coli and 92.3 for S. aureus. For near-infrared light, PK for E. coli reported 52.8 and 99.2 for S. aureus. These results confirm the exciting potential of these nanocomposites to prevent the development of antibiotic resistance and also to open the door for further studies to optimize their composition in order to increase their bactericidal efficacy for biomedical applications.
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This content will become publicly available on February 17, 2026
Photothermal–Photocatalytic Ternary Heterostructure for Solar Light-Driven Highly Efficient Degradation of Antimicrobial Agents and Inactivation of Superbugs
A significant proportion of antimicrobial agents, such as different antibiotics discharged into the environment via human and animal waste, poses significant problems for ecological balance and human health. Moreover, widespread overuse and misuse of antibiotics have led to antibiotic-resistant bacteria (superbugs), which is one of the biggest global health problems in the 21st century. Since the utilization of solar energy, which is an abundant and natural resource for the photocatalytic system, we report the design of a photothermal–photocatalytic dual-functional light absorber-based ternary heterostructure using plasmonic gold nanoparticle (AuNP)-anchored WO3 nanoplatelet (WO3 NPL)-decorated reduced graphene oxide (r-GO) (AuNP/WO3 NPL/r-GO), which exhibits strong absorption between 400 and 900 nm regions and has the capability for the sunlight-driven 100% degradation of doxycycline antibiotics. Herein, we show that due to the excellent photothermal performance of AuNP and r-GO in the heterostructure, the local temperature increased under 785 NIR nm light irradiation, which boosted the photocatalytic degradation reaction kinetics for doxycycline antibiotics via enhancing the transfer of “hot carriers” and the formation of reactive oxygen species (ROS). Furthermore, experimental data indicate that by integrating photothermal–photocatalytic materials, sunlight can be used for 100% doxycycline antibiotic degradation after 80 min of light irradiation. Moreover, we demonstrate that the ternary heterostructure can be used for sunlight-based 100% inactivation of carbapenem-resistant Enterobacteriaceae Escherichia coli (CRE E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) superbugs by just exposing them to light for 60 min. This study sheds light on the construction of photothermally assisted photocatalytic ternary heterostructures for high-efficiency sunlight-driven degradation of antibiotics and superbugs.
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- PAR ID:
- 10614812
- Publisher / Repository:
- acs.org
- Date Published:
- Journal Name:
- ACS Applied Bio Materials
- Volume:
- 8
- Issue:
- 2
- ISSN:
- 2576-6422
- Page Range / eLocation ID:
- 1732 to 1744
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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