Efficient penetration and in situ polymerization of dopamine in biofilms for the eradication.

Dopamine molecules with structural resemblance to exogenous quorum-sensing molecules could penetrate biofilm. Furthermore, the polymerization of these molecules in biofilm could be catalyzed by exogenous supplementary Ferrous ions. The in-situ polymerization of dopamine and following photothermal effect in planktonic bacteria dispersion and biofilm could be confirmed by in vitro results. Utilizing the bactericidal and anti-biofilm effect predominately from photothermal effect, the biofilm-related wound infection can be alleviated, followed by an accelerated healing process. [Display omitted] • The efficient penetration of dopamine into biofilms suggests the potential of bacterial secretion analogs for anti-biofilm strategies. • Dopamine polymerization within biofilm enables antibacterial and antibiofilm functions via contact-active and photothermal effects. • The photothermal effect of polydopamine effectively alleviates biofilm-related infections, thereby accelerating wound healing. Biofilm infections pose a significant clinical challenge, as conventional therapies and even emerging nanoparticles often exhibit limited penetration into biofilms. Herein, we proposed that dopamine, owing to its structural similarity to quorum-sensing molecules, can effectively diffuse into biofilms and undergo in situ polymerization assisted by ferrous ions. After confirming the ferrous-ion-accelerated polymerization of dopamine, we demonstrated that dopamine fully penetrated a 120 μm biofilm and then was in situ polymerized throughout the entire 3D biofilm structure. Consequently, upon 808 nm laser irradiation, the biofilm, along with the Pseudomonas aeruginosa it protected, was effectively eliminated, primarily by the photothermal effect of polydopamine. We finally verified the efficacy of this strategy in infected-wound rat models by observing the reduction in bacterial load, elimination of biofilm, and an accelerated healing process. This work indicates that analogs of bacteria secretions could serve as promising candidates for designing penetrable nanomaterials and suggests an alternative approach to combating biofilm-associated diseases. [ABSTRACT FROM AUTHOR]