An ionic gel incorporating copper nanodots with antibacterial and antioxidant dual functions for deep tissue penetration treatment of periodontitis in rats

The local treatment of periodontitis has recently received extensive attention due to the advantages of mild systemic side effects and a high local drug concentration. But the local drug delivery systems are not widely used in clinical practice, and a major obstacle is the poor tissue permeability. In the present study, we report a copper nanodot based ionic gel (Cu-NDs/IL gel) with favorable tissue penetration capability, and it concurrently exhibits antibacterial and anti-inflammatory functions. A Cu-NDs/IL gel was prepared by loading copper nanodots (Cu-NDs) with triple enzyme-like activities into a multifunctional gel. The derived Cu-NDs/IL gel possesses remarkable antibacterial properties attributed to the peroxidase-like activity of Cu-NDs. In addition, Cu-NDs mimic superoxide dismutase and catalase activities, which endow the gel with excellent free radical scavenging capability in a neutral environment to relieve periodontal inflammation. More importantly, the IL moiety in the Cu-NDs/IL gel promotes the penetration of Cu-NDs into the gingival tissue, wherein the triple enzymatic activity of Cu-NDs may function. In short, the Cu-NDs/IL gel has promising potential to serve as a topical drug for periodontitis by promoting penetration, killing bacteria, and scavenging ROS.