Chitosan modified ultra-thin hollow nanoparticles for photosensitizer loading and enhancing photodynamic antibacterial activities

Int J Biol Macromol. 2021 Sep 1:186:839-848. doi: 10.1016/j.ijbiomac.2021.07.078. Epub 2021 Jul 17.

Abstract

Antibacterial photodynamic therapy (PDT) has attracted extremely attention due to not inducing bacteria to generate resistance. However, the poor utilization and low reactive oxygen species (ROS) field of photosensitizers hinder their further application for antibacterial. Here, we designed ultra-thin hollow silica nanoparticles (UHSN), followed by pore-engineering including covalent anchoring of chitosan (UHSN@CS) for enhanced loading and photodynamic property of photosensitizer. The UHSN@CS exhibit high loading efficiency (80.6%, pH = 6.0) and controllable pH-responsive release for Ce6. Additionally, UHSN@CS can enhance the ROS yield of photosensitizers and effectively adhere to S. aureus, thus enormously enhancing antibacterial performance toward bacteria. Moreover, UHSN@CS-Ce6 can obliterate mature S. aureus biofilm and cause an 81% decrease in the biomass, showing a better therapeutic effect than Ce6 (59.2%) under laser irradiation. In vivo results confirm that UHSN@CS-Ce6 is effective to promote infectious wound regeneration. As photodynamic-based nanoplatforms, UHSN@CS-Ce6 are potential antibacterial agents for skin infection therapy.

Keywords: Antibacterial; Chitosan; Hollow silica nanoparticles; Photodynamic therapy; Photosensitizer.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Biofilms / drug effects
  • Biofilms / growth & development
  • Chitosan / chemistry*
  • Chlorophyllides / chemistry
  • Chlorophyllides / pharmacology*
  • Cricetinae
  • Delayed-Action Preparations
  • Drug Carriers*
  • Drug Compounding
  • Hydrogen-Ion Concentration
  • Models, Animal
  • Nanoparticles*
  • Nanotechnology
  • Photochemotherapy*
  • Photosensitizing Agents / chemistry
  • Photosensitizing Agents / pharmacology*
  • Reactive Oxygen Species / metabolism
  • Staphylococcal Skin Infections / drug therapy*
  • Staphylococcal Skin Infections / microbiology
  • Staphylococcal Skin Infections / pathology
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / growth & development
  • Staphylococcus aureus / metabolism
  • Wound Healing / drug effects
  • Wound Infection / drug therapy*
  • Wound Infection / microbiology
  • Wound Infection / pathology

Substances

  • Anti-Bacterial Agents
  • Chlorophyllides
  • Delayed-Action Preparations
  • Drug Carriers
  • Photosensitizing Agents
  • Reactive Oxygen Species
  • phytochlorin
  • Chitosan