Natural/biodegradable polymers gelatin

In addition to synthetic biodegradable polymers discussed so far, naturally occurring biopolymers have also been used for fabricating implantable dmg delivery systems. Examples of natural biopolymers are proteins (e.g. albumin, casein, collagen, and gelatin) and polysaccharides (e.g. cellulose derivatives, chitin derivatives, dextran, hyaluronic acids, inulin, and starch). 

Gelatin is a natural, protein polymer with good biodegradability and film-forming property. It is an amphoteric, with an isoelectric pH ranging from 5 to 9. 

Hydroxyapatite (HA) nanoparticles are osteoconductive bioactive ceramics that can support bone cell adhesion and proliferation and accelerate bone defects healing. HA is typically added to polymeric nanofibers to increase their mechanical strength. HA, often in the form of needle-like nanoparticles, was electrospun in the presence of synthetic biocompatible and biodegradable polymers such as PLA [5, 58-60] and PLA-PEG-PLA [61], natural polymers such as chitosan [62] and collagen [63, 64], and blends of natural and synthetic polymers such as PVA/chitosan [65] and PCL/gelatin [66]. 

---