Composite hydrogels from carrageenan-cl-carboxymethyl chitosan–PVA incorporated ZiF-8 as dressing material for wound healing applications

The skin is the largest organ of the human body and provides protective protection from the external environment and pathogens that risk injury. Hydrogels are closely biomimic to the inherent extracellular matrix and hold promising applications for wound healing. Herein, we have fabricated composite hydrogels from carrageenan (CG), polyvinyl alcohol (PVA), and carboxymethyl chitosan (CMCs) by incorporating zeolitic imidazolate frameworks (ZiF-8) via a simple blending method using tetraethyl orthosilicate (TEOS) as crosslinker. We have studied the structural, thermal, surface morphology, and elemental composition by advanced characterization techniques using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and energy-dispersive x-ray (EDX). The swelling, degradation, water contact angle, and gel fraction were performed to determine physicochemical properties. It was found that increasing ZiF-8 decreases the swelling in different media and increases degradation in PBS media. With increased gel fraction, the increasing ZiF-8 shifted wettability from more hydrophilicity to less hydrophilicity. The biocompatibility of the composite hydrogels has been evaluated using fibroblast cell lines ( 3T3 ) after different time intervals (24–72 h), and it was found that increasing ZiF-8 caused the mature and spread cell morphology with increasing cell viability and proliferation under controlled in vitro conditions. Similarly, increasing ZiF-8 improved the antibacterial activities against Gram-positive ( Staphylococcus aureus ( S. aureus )) and Gram-negative ( Escherichia coli ( E. coli )), which will provide an extra protective antibacterial shield to support wound healing. We have found that CPC-ZiF-10% was the best dressing material with a complete scarless wound of full-thickness skin wound model using an albino SD rat model. Thus, all the results confirmed the successful fabrication of composite hydrogels with a potential candidate for wound healing applications.

Graphical abstract

The graphical abstract illustrates the fabrication of composite hydrogels incorporated with ZiF-8 into the polymeric matrix of carrageenan, carboxymethyl chitosan, and polyvinyl alcohol and their potential antibacterial and wound healing applications