Biocompatible Polymers

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Transcript of Biocompatible Polymers

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BIOCOMPATIBLE POLYMERS

Presented by:Mr. Birudev KaleM. Pharm. ( Sem. I) Under the guidance

of Dr. N. H. Aloorkar H.O.D., Pharmaceutics. 2

Introduction to Polymers

Classification of polymers

Biocompatible polymersRequirements for polymers

Biocompatibility of polymers

Applications

SummaryReferences

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Biocompatibility testing

CONTENTS

What are polymers?

Monomer

Repeat attachment of monomers

Dimer

Monomer

Polymer

Polymers: Macromolecules formed by joining of repeating structural units called as monomers .(“Poly”-many, “mer” -unit or part).

Covalent bond

“Mono”- one“mer”- part

Two monomers

“Di”- two“mer”- part

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Classification of Polymers

Classification of

polymers

Based on molecular

forces

Based on source

Based on mode of

polymerization

Based on structure

Based on susceptibilit

y of backbone

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Classification based on

source

Natural polymers

e.g. Proteins, Rubber

etc.

Synthetic polymers

e.g. Polythen

e

Semi-synthetic polymers

e.g. Rayon

Cont......

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Classification based on Structure of polymers

Cont........

1. Linear polymers

2. Branched polymers

3. Cross linked or Network polymers

e.g. P.V.C., High density Polythene

e.g. Low density Polythene

e.g. Bakelite

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Cont.......

Classification based on mode of polymerization

Addition polymers

Condensation polymers

e.g. Polythene, Buna-S etc.

e.g. Terylene, Nylon 6 etc.

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Classification based

on molecular

forces

Elastomerse.g. Buna-S,

Buna-N

Fibrese.g. Nylon6,6,

Terylene

Thermoplastic polymerse.g. Polythene

Thermosetting polymers

e.g. Bakelite

Cont…..

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Cont…Classification based on susceptibility of backbone

Non-degradable polymers

Degradable polymers

e.g. Polypropylene, Polyethylene

e.g. Polylactide, Polyglycolid

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Biocompatible polymers are synthetic or natural polymers

used to replace part of a living system or to function in

intimate contact with living tissue.

Biocompatible polymers are intended to interface with

biological systems to evaluate, treat, augment or replace any

tissue, organ or function of the body.

What are biocompatible polymers?

Requirements for biocompatible polymers

Physical properties

Chemical stability

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Biocompatibility of polymers

Biocompatibility term is used to describe the suitability of a polymer for exposure to the body or bodily fluids.

A polymer will be considered biocompatible, if it allows the body to function without any complications such as allergic reactions or other adverse side effects.

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Complications of use of Non-biocompatible polymers

Extended chronic inflammation at the contact point.

Cytotoxicity.

Cell disruption.

Skin irritation.

Thrombosis.

Corrosion of an implant (if used). 14

Biocompatibility testing of polymers

Biocompatibility testing answers two fundamental questions: Is the polymer safe?

Does it have necessary physical and chemical properties?

This consist of in vitro and in vivo assessments that are relevant to the

applications of polymers. A variety of tests are necessary to determine biocompatibility,

depending on the type and application of polymer.Generally ISO 10993 series have been followed across the globe to

standardize the biocompatible testing scheme.15

APPLICATIONSTissue cultureTissue scaffoldsImplantable controlled drug delivery systems Catheters and dialysis tubingArtificial graftsTo fabricate wound closure devicesEnvelopes for the implantation of cardiac devicesStents such as biliary stents, esophageal stents, vaginal stents, lung, Trachea/bronchus stentsCoating on medical devices such as vascular grafts, wound dressings and surgical sealants to improve blood compatibility Wildlife vaccination

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Examples of Biocompatible polymer applications

1. Tissue culture

2. Tissue scaffolds

3. Wildlife vaccination

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Biocompatible polymer for tissue culture

370 cCollapsedstructure

320

cExpandedstructure

PIPA changes properties at different temperatures

How could this property be used for medical applications?

Poly(N-isopropyl acrylamide) “PIPA”

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Growing cell sheets using PIPAPIPA Polymer

1. Coat surface with polymer

2. Apply live cells

3. Allow cells to grow4. Harvest cellsCell can be grown outside the body

Reduce temp.

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Examples of cell sheets

Cardiac cells Skin (epitheliall )cells

Skin cell graft on patient

Cell sheets have great potential to treat many injuries/diseases

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Hydrogels can be formed in biobullets

Solid hydrogels of vaccine

Biobullets(Sugar bullets)

Vaccine delivery to animals

Bullet penetrates target, degrade and releases content

Air rifle delivery

Examples & applications of some polymers

Name of polymer Typical applicationsPolyvinylchloride (PVC)

Blood tubing, as blood bags.

Polytetrafluoroethylene (PTFE)

Tubing, endoscopes, cannulas, catheter linings, Synthetic blood vessels, Surgical sutures.

Polyethersulfone (PES) Tubing, catheters

Polyethylene(PE)

Orthopedic sutures, artificial tendons

Polyetheretherketone (PEEK) Dentistry products, rigid tubing

Polysulfone (PS)

Surgical and medical devices, clamps, artificial Heart components, heart valves

Polypropylene (PP) Heart valves 24

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SUMMARY

REFERENCES

1. V. Prasad Shastri, “Non-Degradable Biocompatible Polymers in

Medicine: Past, Present and Future”, School of Medicine and

Department of Materials Science and Engineering, University of

Pennsylvania, Philadelphia, PA 19104, USA.

2. ISO 7405 (1984): International Organization For Standardization,

Technical Report 7’405, Biological Evaluation of Dental Materials.

3. R. James Christie, “Biocompatible polymers: design, function and

applications”, Utsunomiya girl’s high school, USA.

4. http://www.wikipedia.com/biocompatible polymers.

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Cont........

5. Bhola R., Bhola S.M., Liang H., Mishra B., “Biocompatible

Denture Polymers – A Review” Department of Metallurgical &

Materials Engineering, Colorado School of Mines, Golden, CO

80401.

6. Quansah J.K., “Synthetic polymers for biocompatible

biomaterials”, Materials Literature seminar, September 23,

2004.

7. http://www.zeusinc.com/biocompatible polymers.

8. Hiemenz P.C., Marcel Dekker, “Polymer Chemistry- The Basic

Concepts”, Inc. Publication. Page no. 03.

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