Injectable, Biodegradable and Photothermal Hydrogel with Quorum Sensing Inhibitory Effects for Subcutaneous Fungal Infection Treatment.

Owing to the high invasion depth and easy formation of biofilms, the treatment of subcutaneous fungal infection is intractable and challenging. Herein, we report an injectable and biodegradable hydrogel with bactericidal, quorum sensing inhibition and antioxidant activities for the in situ treatment of subcutaneous fungal infection. The hydrogel (BEPE) was constructed by irradiating mixed bovine serum albumin (BSA), ε-polylysine and epigallocatechin gallate (EGCG)-loaded mesoporous polydopamine (PDA) under near-infrared (NIR) light. BEPE exerted microbicidal effects against Candida albicans (99.5%) and Streptococcus mutans (99.6%) through synergistic photothermal effects and the microbiocidal activity of slowly released ε-polylysine. Moreover, the gently released EGCG from BEPE with relatively high bioavailability, synergistically inhibited and destroyed biofilms by inhibiting quorum sensing between microbes, resulting in an antibiofilm efficiency of 80.5% against C. albicans. An in vivo subcutaneous fungal infection study revealed that BEPE accelerates tissue regeneration via targeted formation, elimination of fungal infection and alleviation of inflammation in situ, thereby promoting wound healing. This biodegradable hydrogel strategy will facilitate the design of multifunctional microbicidal agents for targeted subcutaneous fungal infection treatment.