Near infrared-triggered diketopyrrolopyrrole nanoparticles for photothermal applications against bacterial infections

Abstract

Wound infection caused by bacteria is an important reason that affects the rapid healing of wounds, and the emergence of drug-resistant strains makes the treatment more complicated, which brings great challenges to surgeons. To this end, a DPP derivative (DPP-S) with donor-acceptor-donor (D-A-D) structure has been synthesized, which has near-infrared (NIR) absorption spectrum by introducing thione groups, and exhibits excellent photothermal properties under NIR laser irradiation. DPP-S mediated phototherapy can not only effectively inhibit and destroy Staphylococcus aureus and Escherichia coli biofilm, but also inhibit and destroy methicillin-resistant Staphylococcus aureus biofilm. In a mouse wound infection model, DPP-S-mediated photothermal therapy can effectively fight bacterial infection, promote the formation of new blood vessels and the deposition of collagen fibers, and thus accelerate wound healing. This discovery is of great significance for the development of new photothermal agents and also provides a new direction and possibility for the treatment of clinical infectious diseases.