Nanozyme-incorporated Microneedles for the Treatment of Chronic Wounds.

Acute wounds are converted to chronic wounds due to advanced age and diabetic complications. Nanoenzymes catalyze ROS production to kill bacteria without causing drug resistance, while microneedles (MNs) can break through the skin barrier to deliver drugs effectively. The integration of nanoenzymes into an MNs delivery system can simultaneously improve painless drug delivery and reduce adverse effects. It can also reduce the effective dose of drug sterilization while increasing delivery efficiency and effectively killing wounded bacteria while preventing drug resistance. This paper describes in detail the reasons why nanoenzymes combined with MNs are particularly suitable for the treatment of long-term inflammation and persistent infections in chronic wounds. The antimicrobial properties of different types of metallic nanoenzymes from previous studies were also analyzed, and the mutual reinforcement of MNs made of different materials combined with nanoenzymes was compared. The pooled results showed that the MNs, through material innovation, were able to both penetrate the scab and deliver nanoenzymes and exert additional anti-inflammatory and bactericidal effects. The catalytic effect of some of the nanoenzymes can also accelerate the lysis of the MNs or create a cascade reaction against inflammation and infection. However, the issue of increased toxicity associated with skin penetration and clinical translation remains a challenge. This article reviews the latest published results and corresponding challenges associated with the use of MNs combined with nanoenzymes for the treatment of wounds, providing further information for future research. This article is protected by copyright. All rights reserved.