Originally considered simply another naturally occurring component of a number of tissues, breakthrough findings later disclosed hyaluronan’s (HA) extraordinary biological properties and paved the way for a new era of HA-associated medical applications. HA is, in fact, recognized by many cellular receptors, it can mediate cell migration, proliferation, cell-cell aggregation, it has been shown to promote angiogenesis, and the list goes on. This plethora of activities initially moved attention away from a polymer that was considered a simple carrier of biomolecules and towards its potential use in both treating many diseases and conditions and being involved in drug delivery. Given these premises, medical applications exploiting HA’s different roles have been developed. The focus of this chapter is directed towards the chemical conjugation of HA with small drugs, peptides and proteins. Reviewing the vast body of literature dedicated to this field, an extraordinary range of applications will be outlined. Although HA cannot be considered a polymer that is appropriate for all uses, conjugates specifically designed to exploit some of its biological properties and for numerous specific applications will no doubt enjoy an advantage over other polymeric conjugates.
Keywords: Anti-TNF-α, Anticancer drug, Anticancer therapy, CD44, Doxorubicin, Drug conjugates, Drug delivery, Human growth hormone, Hyaluronan, Hyaluronic acid, Insulin, Interferon alpha, Osteoarthritis, Paclitaxel, Polymer conjugation, Polysaccharide, Protein conjugation, Protein delivery, RHAMM, RNase A, SN38.