Multifunctional nano-delivery system based on DNase I and photodynamic therapy for combatting enterococcus faecalis biofilm infections.

Persistent or refractory apical periodontitis is primarily caused by microbial retention, as conventional root canal treatment often fails to eliminate infections completely, and systemic antibiotic therapy is insufficient to achieve effective concentrations for eradicating bacterial biofilms within root canals. This highlights the urgent need for novel therapeutics offering safe and effective antimicrobial strategies. Antimicrobial photodynamic therapy (aPDT) is a promising approach for root canal disinfection. However, commonly used photosensitizers such as Ce6 suffer from poor water solubility and strong aggregation tendencies, resulting in limited penetration into infected sites. In this study, we developed a DNase I-Lip@Ce6 nanodelivery system by combining deoxyribonuclease I (DNase I) with liposome-encapsulated Ce6. The liposomal carrier facilitated efficient delivery of Ce6 into target bacterial cells, while DNase I degraded extracellular DNA in the biofilm matrix, weakening its protective barrier. This synergistically enhanced Ce6 penetration and therapeutic efficacy, leading to the successful eradication of planktonic Enterococcus faecalis and in vitro biofilms. This strategy offers a novel approach for the precision treatment of persistent oral infections and holds strong potential for clinical translation.