Near-Infrared Light-Triggered NO Nanogenerator for Gas-Enhanced Photodynamic Therapy and Low-Temperature Photothermal Therapy to Eliminate Biofilms

Abstract

Junjuan Li,1,* Yue Tian,2,* Qi Qin,2,* Zhaolei Ding,1 Xue Zhao,3 Wei Tan1 1Department of Respiratory Medicine, The First Affiliated Hospital of Weifang Medical University/Weifang People’s Hospital, Weifang, 261000, People’s Republic of China; 2School of Clinical Medicine, Weifang Medical University, Weifang, 261053, People’s Republic of China; 3Department of Laboratory Medicine, The First Affiliated Hospital of Weifang Medical University/Weifang People’s Hospital, Weifang, 261000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Wei Tan, Department of Respiratory Medicine, Weifang People’s Hospital, 151 Guangwen Street, Weifang, Shandong Province, 261000, People’s Republic of China, Email [email protected] Xue Zhao, Department of Laboratory Medicine, Weifang People’s Hospital, 151 Guangwen Street, Weifang, Shandong Province, 261000, People’s Republic of China, Email [email protected]: Owing to its noninvasive nature, broad-spectrum effectiveness, minimal bacterial resistance, and high efficiency, phototherapy has significant potential for antibiotic-free antibacterial interventions and combating antibacterial biofilms. However, finding effective strategies to mitigate the detrimental effects of excessive temperature and elevated concentrations of reactive oxygen species (ROS) remains a pressing issue that requires immediate attention.Methods: In this study, we designed a pH-responsive cationic polymer sodium nitroside dihydrate/branched polyethylenimine–indocyanine green@polyethylene glycol (SNP/PEI-ICG@PEG) nanoplatform using the electrostatic adsorption method and Schiff’s base reaction. Relevant testing techniques were applied to characterize and analyze SNP/PEI-ICG@PEG, proving the successful synthesis of the nanomaterials. In vivo and in vitro experiments were performed to evaluate the antimicrobial properties of SNP/[email protected]: The morphology and particle size of SNP/PEI-ICG@PEG were observed via TEM. The zeta potential and UV-visible (UV‐vis) results indicated the synthesis of the nanomaterials. The negligible cytotoxicity of up to 1 mg/mL of SNP/PEI-ICG@PEG in the presence or absence of light demonstrated its biosafety. Systematic in vivo and in vitro antimicrobial assays confirmed that SNP/PEI-ICG@PEG had good water solubility and biosafety and could be activated by near-infrared (NIR) light and synergistically treated using four therapeutic modes, photodynamic therapy (PDT), gaseous therapy (GT), mild photothermal therapy (PTT, 46 °C), and cation. Ultimately, the development of Gram-positive (G+) Staphylococcus aureus (S. aureus) and Gram-negative (G−) Escherichia coli (E. coli) were both completely killed in the free state, and the biofilm that had formed was eliminated.Conclusion: SNP/PEI-ICG@PEG demonstrated remarkable efficacy in achieving controlled multimodal synergistic antibacterial activity and biofilm infection treatment. The nanoplatform thus holds promise for future clinical applications.Keywords: cationic, mild photothermal, photodynamic, NO gas, antibacterial

Keywords

• mild photothermal
• photodynamic
• no gas
• antibacterial