Hyaluronate derivatives in drug delivery.

Hyaluronan (HA), an abundant nonsulfated glycosaminoglycan component of synovial fluid and the extracellular matrix, is an attractive building block for new biocompatible and biodegradable polymers that have applications in drug delivery, tissue engineering, and viscosupplementation. This review consists of three subtopics: (i) chemical modification of HA; (ii) physicochemical and biochemical characterization of HA derivatives; and (iii) in vitro and in vivo bioevaluation studies. Important new products have already reached the marketplace, and the approval and introduction of a variety of new medical applications of HA-based biomaterials can be anticipated in the next decade.