Evaluation of a Peptide-Based Coassembled Nanofibrous and Thixotropic Hydrogel for Dermal Wound Healing.

The development of a peptide-based coassembled thixotropic hydrogel is a promising biomaterial, which could be used for dermal wound healing application. Cyclodextrins are widely used as biocompatible cyclic oligosaccharides that have hydrophilic exterior and hydrophobic interior for the formation of functional biomaterials. The current work presents a paradigm of a coassembled hydrogel with suitable mechanical strength that exhibits in vivo wound healing efficacy. In this report, we have designed and synthesized an Amoc (9-anthracenemethoxycarbonyl)-capped dipeptide, which self-assembles into a tough and robust hydrogel owing to participation of various noncovalent interactions. The mechanical strength of the self-assembling peptide-based hydrogel is tuned by incorporation of equimolar β-cyclodextrin (CD), which leads to the formation of a coassembled hydrogel suitable for wound healing application. The coassembled hydrogel exhibits simple syringe injectability and is thixotropic in nature. The nanostructural morphology of the coassembled hydrogel reveals a highly cross-linked and entangled nanofibrillar network. Several spectroscopic data elucidate the presence of noncovalent interactions between CD and peptide, which could be the driving force for the formation of ordered nanostructures. The coassembled hydrogel shows potent antibacterial activity against Gram-positive pathogenic bacteria. In vitro biocompatibility of the coassembled hydrogel has been investigated with the human embryonic kidney (HEK293) and MCF-7 cell lines. Additionally, confocal laser scanning microscopic data show cellular uptake of the coassembled hydrogel with blue fluorescence. Moreover, the in vivo wound healing activity of the coassembled hydrogel has been investigated by the histopathology study. The biochemical parameters such as nitric oxide and collagen contents have been evaluated by Griess and hydroxy proline assays. All the results corroborate the wound healing efficacy of a nanofibrillar antibacterial coassembled hydrogel.