Hi hemant,

Both natural and synthetic polymers have been used for biomedical applications. Natural polymers, such as collagen, chondroitin sulphate , chitin , and chitosan are widely used for tissue engineering and organ regeneration, since they facilitate cell attachment and maintenance of differentiation. Synthetic polymers such as poly(-caprolactone) (PCL), poly(lactic acid) (PLA), poly(glycolic acid) (PGA), poly(lactic-co-glycolic acid) (PLGA), and other synthetic polymers can provide extreme versatility regarding the control of their physicochemical properties and are generally easy to process into tissue engineering scaffolds . Synthesis of these polymers can be tailored to yield a specific molecular weight, chemical structure, end group chemistry, and composition (homopolymers, copolymers, and polymer blends) in terms of tissue response. Furthermore, the biodegradation time of synthetic polymers makes them more attractive over natural ones . 

Hi Hemant,

Great answer above. Obviously the choice in biopolymer is highly dependant on its proposed function.

Interestingly there is a lot of work being conducted using natural biopolymers, adapted to have synthetic polymer qualities; an example such as Shrilk, perhaps.

You need to really understand what the biopolymer will be used for, and how this will influence its structural or chemical requirements.