Biodegradable polymers based on bile acids and potential biomedical applications

Bile acids are natural compounds that play an important biological role in the body. They are candidates of choice as building blocks of biocompatible and degradable polymers. Bile acids have been incorporated into biodegradable polymeric structures as pendant moieties on natural polymers, such as dextran and chitosan, and as the core component of the backbone of synthetic polymers and dendrimers. In the two latter cases, linkage of the repeating units relies on anhydride, ester or amide bonds. Owing to the rigidity of the steroidal polycyclic backbone and the amphiphilic properties of bile acids, materials based on these compounds can display interesting tunable properties. Therefore, biodegradable polymers based on bile acids are of particular interest to the fields of drug delivery, where their amphiphilic properties can be used to encapsulate drugs, and tissue engineering, where their rigid steroidal backbone make them good candidates for controlling the mechanical properties of the materials.