Polydopamine-based nanospheres as nanoplatforms to kill Staphylococcus aureus and to promote wound healing by photothermal therapy

Bacterial infections have always been a threat when it comes to public health accounting for increased morbidity and mortality rates around the world. For the first time, Polydopamine is often used as an ocular surface drug delivery medium to treat some ocular surface diseases based on its good tissue affinity. Mesoporous polydopamine nanospheres (MPDA NPs) under photothermal therapy (PTT) are demonstrated as efficient therapeutic nanoplatforms for Staphylococcus aureus (S. aureus) infection and wound healing. MPDA NPs were found to exhibit excellent photothermal performance, significantly causing an increase in temperature within a short period of NIR-I exposure (808 nm, 1 W cm−2, 6 min). The MPDA NPs under the NIR irradiation remarkably eliminated S. aureus in vitro. Moreover, these synergistic effects turnouts to be phenomenal in vivo, effectively killing and healing S. aureus-infected abscesses in mice. These revealed the combined effect of the intrinsic antibacterial activity of MPDA NPs enhanced upon NIR-I exposure. Hence, MPDA NPs under NIR-I could prove excellent therapeutic nanoplatforms for bacteria-related infections and other biomedical applications.