Robust hydrogel networks from poly (ethylene glycol) and collagen for vocal fold replacement

Normal vocal folds function to control the airway and produce voice. Voice is produced through vibrations of the vocal fold cover, also known as the lamina propria, that is largely dependent on the viscoelasticity and tissue composition of the vocal fold extracellular matrix (ECM). Vocal fold scarring or paralysis can cause dysphonia by changing the vocal fold viscoelasticity. Clinical therapeutic treatments with biomaterials are limited due to immunogenicity, fast body resorption, weak mechanical properties, etc. A biomaterial scaffold that mimics the lamina propria ECM and provides the biomechanical properties of the vocal fold is favorable. Injectable PEG-collagen hydrogels with semi-interpenetrating networks were developed to offer a potential alternative treatment option for vocal fold replacement. Covalently crosslinked PEG and physically crosslinked collagen formed semi-interpenetrating networks. Mechanical strength of hydrogels is mainly dependent on PEG concentration. Incorporation of collagen into PEG networks enhanced hydrogel viscoelasticity, elongation, and also some biological properties. Experimental data showed that this hydrogel system exhibited tunable mechanical properties and also support cell adhesion and proliferation in vitro. The findings and results from this project support the prospect of a new biomaterial for vocal fold repair application