Mechanics Mediated Semi‐Convertible Hydrogel Enabled Sustained Drug Release

A mechanics-mediated semi-convertible hydrogel (M_echSCH) system that combines thixotropic supramolecular non-covalent networks N-phenylmethoxycarbonyl-L-tryptophan (NLFT) networks with polyvinyl alcohol/Gelatin polymer networks. NLFT supramolecular segments undergo disassembly when subjected to mechanical stress as low as 9.04 Pa, during which the M_echSCH exhibits a partial gel-sol transition. This transition facilitates the migration of the sol layer toward to the interface, promoting the sustained release of the loaded Platelet-Derived Growth Factor (PDGF) from the hydrogel matrix, ultimately facilitating dynamic wound healing process.

Abstract

The dynamic mechanic environment surrounding the wound may retard wound healing, and even lead to an exacerbation of inflammation and scar. How to actively promote wound healing under a dynamic mechanical environment during human motion is still a long-standing challenge. Therefore, a mechanics mediated semi-convertible hydrogel (M_echSCH) loaded with drug is proposed in this study employing the synergistic interaction between mechanics mediated supramolecular non-covalent networks and polyvinyl alcohol/Gelatin polymer networks for enhancing dynamic wound healing. The formed M_echSCH exhibits a partial gel-sol transition even under a shear stress of ≈9.04 Pa that is satisfied with most tissues or organs' stress. The sustained release of encapsulated drugs would be efficiently compared with the mechanics of non-sensitive polyvinyl alcohol/Gelatin hydrogel. The loaded platelet-derived growth factor (PDGF) of the M_echSCH exhibited a rapid onset of therapeutic effect in a mice dorsal full-thickness dermal wound model, which demonstrated sustaining drug release through mechanics of skin tension at the wound site, along with alleviating the inflammation and promoting rapid vascular regeneration. This mechanics mediated semi-convertible hydrogel presents potential clinical applications for the dynamic management of chronic wounds.