Visualizing Active Sites in Electrospun Photoactive Membranes via Fluorescence Lifetime Imaging

Angew Chem Int Ed Engl. 2024 Dec 9;63(50):e202414412. doi: 10.1002/anie.202414412. Epub 2024 Nov 7.

Abstract

Interest in antibacterial nanomaterials has surged in recent years, driven by the rise in antibiotic resistance among microbes. However, their practical application remains limited because many crucial properties have yet to be thoroughly investigated. In this study, we have developed novel nanofibrous membranes based on hydrophilic polyacrylonitrile (PAN) or hydrophobic polycaprolactone (PCL) with embedded hydrophilic or hydrophobic zinc(II)phthalocyanines (ZnPcs) as photosensitizers and investigated their water disinfection properties. Several key characteristics were evaluated to link the activity of the material and composition/structure. As demonstrated by reflectance UV/Vis spectroscopy, the aggregation states of dyes within the polymer support vary significantly. We have proposed and validated the use of fluorescence lifetime imaging (FLIM) for visualizing "active sites" in the membranes. The results of this study provide useful insights for the engineering of photoactive nanomaterials with tailor-made properties and highlight the crucial role of the nature of polymeric support in modulating the material's activity.

Keywords: antimicrobial resistance; electrospun nanomaterials; membranes; one-health; photodynamic inactivation; reactive oxygen species.

MeSH terms

  • Acrylic Resins / chemistry
  • Fluorescent Dyes / chemistry
  • Hydrophobic and Hydrophilic Interactions
  • Indoles / chemistry
  • Isoindoles
  • Membranes, Artificial
  • Nanofibers / chemistry
  • Optical Imaging*
  • Organometallic Compounds / chemistry
  • Photosensitizing Agents / chemistry
  • Photosensitizing Agents / pharmacology
  • Polyesters / chemistry
  • Zinc Compounds / chemistry

Substances

  • polyacrylonitrile
  • Indoles
  • Polyesters
  • polycaprolactone
  • Acrylic Resins
  • Organometallic Compounds
  • Zinc Compounds
  • Zn(II)-phthalocyanine
  • Isoindoles
  • Photosensitizing Agents
  • Membranes, Artificial
  • Fluorescent Dyes