NIR dye-based electrospun fibers for antimicrobial photodynamic therapy

Abstract

AbstractAntimicrobial photodynamic therapy (aPDT) has emerged as a promising strategy to improve antimicrobial treatment and face the antibiotic resistance to conventional therapy. Among the different photosensitizers, Near Infrared (NIR) polymethine dyes (Squaraines, SQs and Cyanines, CYs) have attracted considerable attention although, their poor aqueous solubility and stability still limit their application. Their incorporation inside nanoparticles (NPs) or into electrospun fibers, could help to prevent dye aggregation, protect their photochemical properties, and play a key role in the infection treatment.Cys and SQs were characterized before and after the incorporation, showing improved optical properties and photostability. In addition, their ability to produce Reactive Oxygen Species (ROS), responsible of bacterial death, was evaluated, proving that the ROS generation ability is preserved after the incorporation. Furthermore, in vitro antimicrobial studies against Gram-negative and Gram-positive models showed a good antimicrobial effect after the irradiation, confirming the potential of these nanophotosensitizers for aPDT in the local treatment of infections.