Carbonized Polymer Dot‐Tannic Acid Nanoglue: Tissue Reinforcement with Concurrent Fluorescent Tracking, Insulin Delivery, and Reactive Oxygen Species Regulation for Normal and Diabetic Wound Healing

Abstract

Nanotizing biosealant components offer a multitude of chemical functionalities for superior adhesion–cohesion, delivering unique properties for comprehensive wound healing that are otherwise impossible to achieve using commercial variants. For the first time, a two‐step controlled hydrothermal pyrolysis is reported to nanotize dopamine, phloroglucinol, and glutaraldehyde into carbon dot (CD) to be subsequently converted into carbonized polymer dot (CPD) with gelatin as a co‐substrate. Chemical crosslinking of CD with gelatin through Schiff base formation before the second pyrolysis step ensures a complex yet porous polymeric network. The retention of chemical functionalities indigenous to CD substrates and gelatin along with the preservation of CD photoluminescence in CPD for optical tracking is achieved. A unique nanoformulation is created with the CPD through tannic acid (TA) grafting evolving CPD‐TA nanoglue demonstrating ≈1.32 MPa strength in lap shear tests conducted on porcine skin, surpassing traditional bioadhesives. CPD‐TA nanoglue uploaded insulin as chosen cargo disbursal at the wound site for healing normal and in vitro diabetic wound models using HEKa cells with extraordinary biocompatibility. Most importantly, CPD‐TA can generate reactive oxygen species (ROS) and scavenge simultaneously under ambient conditions (23 W white LED or dark) for on‐demand sterilization or aiding wound recovery through ROS scavenging.