Review of Polyhydroxyalkanoates Materials and other Biopolymers for Medical Applications

Polyhydroxyalkanoates (PHAs) and other biopolymers vary in their behavior and properties, but are extremely useful in medical applications because of their biodegradability. As long-term problems arise with permanent implants, different biopolymers can be selected and blended to replace the old PHAs and other homopolymers with new, less invasive alternatives. Scaffolds and surgical meshes are not designed to fuse with regrown tissue, but are intended to both guide new tissue and degrade when they are no longer required. The mechanical properties, characteristic length, and degradation profile of scaffold biopolymers are the key concerns in their medical application. Although the PHA and other biopolymers have excessively long degradation times, blending tough polymers with less durable polymers may alleviate the problems. The hydrophobic polymers must be balanced with their cytotoxicity; therefore, additional focus is being placed on changing the surface properties through grafting.