Polymers related with Controlled drug delivery system

Polymers

1. POLYMERS Presented By: Mr. Pradip F. Sontakke Assistant professor Dept. of Pharmaceutics SHREE SAMBHAJI COLLEGE OF PHARMACY KHADKUT , NANDED .

2. 1 . Matrix Systems Polymers are used to form a matrix that encapsulates the drug. The drug is dispersed throughout the polymer matrix and is released by diffusion and/or degradation of the polymer. Common polymers used in matrix systems include: Eg Hydroxypropyl methylcellulose (HPMC), Ethylcellulose , Polyvinyl alcohol (PVA). 2. Reservoir Systems In reservoir systems, the drug is surrounded by a polymer membrane that controls the rate of drug release. The release rate can be adjusted by modifying the polymer's properties. Typical polymers include: Eg. Polyurethane , Ethylene -vinyl acetate (EVA) , Silicone elastomers Application of polymers in formulation of controlled release formulation

3. 3. Bio adhesive Systems Polymers with bio adhesive properties can adhere to biological tissues, such as the mucosal membranes, enhancing drug absorption and prolonging residence time. Examples include: Chitosan , Carbopol , Polycarbophil. 4. Hydrogels Hydrogels are three-dimensional polymer networks that can swell in water and hold a large amount of water while maintaining their structure. They are used in CRDDS for their ability to release drugs in a controlled manner through diffusion and swelling mechanisms. Common hydrogels include: Polyethylene glycol (PEG),Polyvinyl alcohol (PVA) , Polyacrylamide.

4. 5. Microspheres and Nanoparticles Polymers are used to form microspheres and nanoparticles that encapsulate the drug, protecting it from degradation and controlling its release. These particles can be designed to release the drug over a prolonged period. Polymers used include: Polylactic acid (PLA) , Polyglycolic acid (PGA),Poly(lactic-co-glycolic acid) (PLGA) 6. Transdermal Systems Polymers are used in transdermal patches to control the release of drugs through the skin. These systems provide a steady release of drugs over an extended period. Commonly used polymers include: Polyisobutylene , Polyacrylate , Silicone -based adhesives

5. Osmotic Systems Polymers are used in osmotic drug delivery systems, where the drug is released through a semi-permeable membrane driven by osmotic pressure. Polymers used in these systems include: Cellulose acetate , Polyethylene oxide 8. Implantable Systems Polymers are used to create implantable devices that release drugs over a long period. These devices can be biodegradable or non-biodegradable, depending on the application. Examples include: Polylactic acid (PLA) , Poly(lactic-co-glycolic acid) (PLGA) , Polycaprolactone (PCL)

6. In Situ Forming Systems Certain polymers can form gels or solidify upon contact with body fluids, creating a depot that releases the drug over time. Polymers used in these systems include: Poloxamers Poly(lactic-co-glycolic acid) (PLGA) Chitosan