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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., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Bioadhesives with all-inclusive properties for simultaneous strong and robust adhesion, cohesion, tracking, drug delivery, self-sterilization, and nontoxicity are still farfetched. Herein, a carbon dot (CD) is made to infuse each of the above-desired aspects with gelatin, an inexpensive edible protein. The CD derived through controlled hydrothermal pyrolysis of dopamine and terephthaldehyde retained -NH 2 , -OH, -COOH, and, most importantly, -CHO functionality on the CD surface for efficient skin adhesion and cross-linking. Facile fabrication of CD-gelatin bioadhesive through covalent conjugation of -CHO of the CD with -NH 2 of gelatin through Schiff base formation was accomplished. This imparts remarkable self-healing attributes as well as excellent adhesion and cohesion evident from physicomechanical analysis in a porcine skin model. Improved porosity of the bioadhesive allows loading hemin as a model drug whose disembarkment is tracked with intrinsic CD photoluminescence. In a significant achievement, antibiotic-free self-sterilization of bioadhesive is demonstrated through visible light (white LED, 23 W)-irradiated photosensitization of the CD to produce reactive oxygen species for annihilation of both Gram-positive and Gram-negative bacteria with exceptional efficacy (99.9%). Thus, a comprehensive CD-gelatin bioadhesive for superficial and localized wound management is reported as a promising step for the transformation of the bioadhesive domain through controlled nanotization for futuristic clinical translations.

In the case of thermoplastic elastomers (TPEs) based on nonpolar polypropylene (PP) and polar rubbers, a small quantity of a third component known as the compatibilizer is added to maximize the compatibility between the incompatible blend components. Generally, one part of the compatibilizer reacts with the nonpolar PP phase and the other part of the compatibilizer reacts with the polar rubber phase, which in turn produces TPEs with useful properties. Till today, there have been no reports in the literature that examine the effect of a compatibilizer that can have multifaceted interactions with the incompatible blend components for the development of TPEs with unique properties. Accordingly, here, an ethylene-acrylic ester-maleic anhydride terpolymer (E-AE-MA-TP) has been used as the compatibilizer for the preparation of TPEs based on nonpolar isotactic polypropylene (i-PP) and polar epichlorohydrin rubber (ECR). The E-AE-MA-TP compatibilizer contains ethylene groups, acrylic groups, and anhydride/acid groups along its backbone, which act as the sites for establishing multifaceted interactions with both i-PP and ECR. The compatibilization efficiency of the E-AE-MA-TP compatibilizer has been analyzed by contact angle measurements, Fourier transform infrared (FTIR) spectroscopy, tensile stress-strain studies, mixing torque profiles, rheological studies, differential scanning calorimetry (DSC), field emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM) images. The particle size of the dispersed ECR domains in the i-PP matrix of the i-PP/ECR blend prominently decreases (∼90% reduction) by incorporation of a very low dosage (5 wt %) of the E-AE-MA-TP compatibilizer. The i-PP/ECR (40 wt %/60 wt %) blend containing 5 wt % compatibilizer displays outstanding mechanical properties (especially strain at break value (∼370%)), which are superior to the mechanical properties of several compatibilized TPEs (based on PP and polar rubbers) reported in the literature. The unique properties of TPEs based on i-PP and ECR in the presence of the E-AE-MA-TP compatibilizer is attributed to the efficacy of the E-AE-MA-TP compatibilizer to establish multifaceted interactions with both i-PP and ECR., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)