Injectable Hydrogels for Cartilage Regeneration

Abstract

Hydrogels are three-dimensional network structures able to imbibe large amounts of water. Hydrogels do not typically dissolve due to chemical or physical cross-links and/or chain entanglements. They exist naturally in the form of polymer networks such as collagen or gelatin, or can be made synthetically. Environmentally sensitive hydrogels can serve a wide variety of applications because of their ability to respond to environmental changes, typically by exhibiting changes in volume. Traditional stimuli that elicit hydrogel response are pH, temperature, and ionic strength. Analytes and biomarkers including glucose, proteins, and DNA also elicit hydrogel responses. Because of such a wide variety of response triggers, hydrogels can be incorporated into sensors or actuators, or can be utilized in controlled drug delivery systems, biosensors, tissue engineering scaffolds, artificial organs, wound healing bandages, physiological membranes, contact lenses, and microfluidic valves. © 2012 Elsevier B.V. All rights reserved.