Enhanced Neovascularization Using Injectable and rhVEGF‐Releasing Cryogel Microparticles

Cryogels are gel networks or scaffolds with a large porous structure; they can be tailored for injectability and for possessing a shape-memory ability. Herein, a growth factor-releasing cryogel microparticle (CMP) system is fabricated, and the therapeutic efficacy of recombinant human vascular endothelial growth factor (rhVEGF)-loaded CMP (V-CMP) for neovascularization is investigated. To prepare the cryogels, both methacrylated chitosan (Chi-MA) and methacrylated chondroitin sulfate (CS-MA) are used, and crosslinking using a radical crosslinking reaction is established. The physical, mechanical, and biological properties of the cryogels are analyzed by varying the amount of CS-MA used. The cryogels are then pulverized, and microsized CMPs are fabricated. CMPs dispersed in saline demonstrate a shear-thinning property, and can thus be extruded through a 23G needle. Additionally, V-CMP exh…