biodegradable polymers pptx

Biodegradable polymers

1. Biodegradable Polymers Guided By : Miss snehal pardeshi Presented By : Darshana bafna

2. BIODE G RAD A BLE POLY M ERS Biodegradable polymers are defined as polymers comprised of monomers linked to one another through functional groups and have unstable links in the backbone. They are broken down into biologically acceptable molecules that are metabolized and removed from the body via normal metabolic pathways. Based on biodegradability polymers are classified as: Biodegradable polymers eg: collagen, poly glycolic acid etc., Non biodegradable polymers eg: poly vinyl chloride, polyethylene etc., 5

3. Polymer Degradation Polymer degradation is a change in the properties – tensile strength, colour, shape, etc of a polymer or polymer based product under the influence of one or more environmental factors such as heat, light or chemicals. The term 'biodegradation' is limited to the description of chemical processes (chemical changes that alter either the molecular weight or solubility of the polymers ) The process carried out by Biological system ( micro organism ) where in polymer chain Cleaved by enzymatic activity . 7

4. Classification of biodegradable polymers

5. Classification of biodegradable polymers based on the source Synthetic biodegradable polymers: eg: Aliphatic poly(esters) Polyanhydrides Polyphosphazenes polyaminoacids Poly orthoesters Natural biodegradable polymers: eg: Albumin Collagen Dextran Gelatin 11

6. Synthetic biodegradable polymers 1) Aliphatic poly(esters) These are p repared b y ring o p e n i n g and p o l y m er i z at ion of cyclic ester. Aliphatic polyesters include: POLY (GLYCOLIC ACID) POLY (LACTIC ACID) POLY (CAPROLACTONE) POLY (GLYCOLIC ACID) ---(--O—C-CH 2 ---) n --(--O---C—CH---) n PO L Y (LAC T IC A C ID) 12

7. Natural biodegradable polymers Natural polymers are an attractive class of biodegradable polymers as they are: Derived from natural sources Easily available Relatively cheap eg: Albumin Collagen Dextran Gelatin Pectin, starch etc., 19

8. FACTO R S AFFECTI N G BI O DE G RA D ATI O N OF POLYMERS Morphological factors Shape & size Variation of diffusion coefficient and mechanical stresses Chemical factors Chemical structure & composition Presence of ionic group and configuration structure Molecular weight and presence of low molecular weight compounds Physical factors Processing condition Sterilization process

9. ADVANTAGES OF BIODEGRADABLE POLYMERS Localized delivery of drug Sustained delivery of drug Stabilization of drug Decrease in dosing frequency Reduce side effects Improved patient compliance Controllable degradation rate

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