Controlled Degradation and Mechanical Behavior of Photopolymerized Hyaluronic Acid Networks

TLDR

Hyaluronic acid is a natural polysaccharide with desirable biomaterial properties, notably as a scaffold for tissue engineering. The study seeks to advance in‑vivo curable biomaterials by methacrylic‑anhydride‑modified hyaluronic acid photopolymerized into networks with tunable physical properties. Hyaluronic acid of 50–1100 kDa was methacrylated and photopolymerized to produce networks whose physical properties could be tuned. Networks containing 2–20 wt % macromer exhibited swelling ratios of ~42–8, compressive moduli of ~2–>100 kPa, and degradation times of <1–38 days in 100 U/mL hyaluronidase; 3T3 fibroblasts remained viable at low macromer concentrations but viability declined with higher concentrations, while auricular swine chondrocytes generated neocartilage when encapsulated.

Abstract

Hyaluronic acid is a natural polysaccharide found abundantly throughout the body with many desirable properties for application as a biomaterial, including scaffolding for tissue engineering. In this work, hyaluronic acid with molecular weights ranging from 50 to 1100 kDa was modified with methacrylic anhydride and photopolymerized into networks with a wide range of physical properties. With macromer concentrations from 2 to 20 wt %, networks exhibited volumetric swelling ratios ranging from ∼42 to 8, compressive moduli ranging from ∼2 to over 100 kPa, and degradation times ranging from less than 1 day up to almost 38 days in the presence of 100 U/mL of hyaluronidase. When 3T3-fibroblasts were photoencapsulated in the hydrogels, cells remained viable with low macromer concentrations but decreased sequentially as the macromer concentration increased. Finally, auricular swine chondrocytes produced neocartilage when photoencapsulated in the hyaluronic acid networks. This work presents a next step toward the development of advanced in vivo curable biomaterials.