Biopolymers

 

Biopolymers are natural polymers that are produced by the cells of living organisms. Biopolymers consist of monomeric units that are covalently bonded to form bulky molecules.  Three main classes of biopolymers are classified according to the monomers units used and the structure of the biopolymer formed polynucleotides, polypeptides, and polysaccharides. Polynucleotides, such as RNA and DNA, are the long chain polymers and composed more than 13 polymeric units.

The major difference between biopolymers and synthetic polymers can found in their structures. All polymers are made of repetitive units called as monomers. Biopolymers often have a well-defined structure, though this is not a defining characteristic but the exact chemical composition of the sequence in which these units are arranged is called the primary structure, in case of proteins. Many biopolymers coils together to form secondary as well as tertiary structure.

Some biopolymers are:

Collagens- It has high tensile strength and is a non-toxic in nature, easily absorbable, biodegradable and biocompatible material.

 Gelatine- There is two types of gelatin Type A and Type B. Type A gelatin derived by acid hydrolysis of collagen and has 18.5% nitrogen content. Type B gelatin is derived of alkaline hydrolysis containing 18% of nitrogen and no amide groups are present.

 Starch- They are less expensive biodegradable biopolymer and has poor mechanical properties due to its sensitivity to moisture

 Cellulose- It is structured with stacked chains that result in stability and strength. The strength and the stability come from the straighter shape of cellulose caused by glucose monomers joined together by glycogen bonds. They are biocompatibility, and environmentally friendly in nature.