Stereogenic Harmony Fabricated Mechanoresponsive Homochiral Triphenylalanine Analogues with Synergistic Antibacterial Performances: A Potential Weapon for Dermal Wound Management.

Abstract

The wound recovery phenomenon remains as one of the long challenging concerns worldwide. In search of user-friendly dressing materials, in this report, we fabricated a rational combinatorial strategy utilizing stereogenic harmony in a triphenylalanine fragment and appending it to δ-amino valeric acid at the N-terminus (hydrogelators I-VII) such that a potential scaffold could be fished out from the design. Our investigations revealed that all the hydrogelators displayed not only excellent self-healing performance as well as high mechanical strength at physiological pH but also mechanical stress-triggered gel-sol-gel transition properties. The structural and morphological investigation confirmed the presence of β-sheet-like assemblies stabilized by intermolecular H-bonding and π-π interactions. Moreover, these scaffolds showed substantial antibacterial as well as antifungal efficacy against common wound pathogens, i.e, four Gram-positive bacteria (Staphylococcus aureus, Streptococcus mutans, B. subtilis, E. fecalis), four Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia, P. aerugonosa, Proteus spp.), and two fungal strains (C. albicans and A. niger). The manifestation of consistent antioxidant properties might be due to the enhancement of amphiphilicity in hydrogelators, which has led to the generation of reactive oxygen species (ROS) in a facile manner, a probable mechanism to damage the microbial membrane, the driving force behind the antimicrobial efficacy. Also, the constructs exhibited proteolytic resistance and remarkable biocompatibility toward mammalian cells. Thus, based on the above benchmarks, the homochiral hydrogelator IV was seived out from a pool of seven, and we proceeded toward its in vivo evaluation using full-thickness excisional wounds in Wister rats. The scaffolds also accentuated the re-epithelialization as well in comparison to the negative control, thereby facilitating the wound closure process in a very short span of time (10 days). Overall, our in vitro and in vivo analysis certifies hydrogelator IV as an ideal dressing material that might hold immense promise for future wound care management.