Multi-modal antibacterial lignin-based nanocomposites with photothermal and free radical therapy for bacterial infection treatment

Area of Science:

• Biomaterials Science
• Nanotechnology
• Infectious Diseases

Background:

• Bacterial infections pose a significant global health threat, compounded by increasing antimicrobial resistance.
• Developing novel therapeutic strategies beyond conventional antibiotics is crucial.

Purpose of the Study:

• To develop and evaluate a smart, thermo-responsive antibacterial nanocomposite for synergistic therapy.
• To investigate the combined effects of photothermal therapy and free radical generation against bacterial infections.

Main Methods:

• Synthesis of lignin-stabilized gold nanoparticles (LNPs-AuNPs) forming sea urchin-like structures.
• Incorporation of an azo compound (AIPH) for oxygen-independent radical generation upon heating.
• In vitro and in vivo evaluations using bacterial cultures and a rat skin infection model.

Main Results:

• LNPs-AuNPs exhibited efficient photothermal conversion under near-infrared irradiation.
• The nanocomposite demonstrated synergistic antibacterial activity against Staphylococcus aureus and Escherichia coli.
• In vivo studies showed reduced inflammation and accelerated tissue healing in infected rat models.

Conclusions:

• The developed LNPs-Au/AIPH nanocomposite presents a promising antibiotic-free strategy for combating bacterial infections.
• This dual-mode nanoplatform offers enhanced therapeutic efficacy with potentially minimal side effects.
• Further research into this nanoplatform could lead to advanced treatments for resistant bacterial infections.