biomaterials bose rjc
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Biomaterials
Dr. Rajendran JC Bose M.Pharm. PhD
The reason why we are doing?
“A material intented to interface with biological systems to evaluate, treat, augment or replace any tissue, organ or function of the body.
Biomaterials-An Interdisciplinary field
Evolution of Biomaterial Science .
1st generation (since 1950s)
Objective: Bioinertness.
2nd generation (since 1980s)
Objective : Bioactivity
3rd generation (since 2000s)
Objective : Regenerate functional tissue
Biomaterials
20
17
201
2CAGR
15%
$44.0 billion
$88.4 billion
20000
15000
10000
5000Reve
nue
in $
Mill
ion
Metals
Ceramics
Polymers Others
USA EuropeAsia ROW
Reve
nue
in $
Mill
ion
2009 2014
Orthopedic38%
Cardio vascu-
lar37%
Wound care
9%
Plastic surger
y8%
Urological4%
Gastro2% Others
2%
Biomaterial Product Market
Biomaterial market status,
Biocompatibility: The ability of a material to perform with an appropriate host response in a specific application.
Cell-biomaterial interaction
Biocompatibility
• The application of engineering disciplines to either maintain existing tissue structures or ti enable tissue growth.
• From a material engineering pint of view, tissues are considered to be cellular composites representing mltiphase system:
Three main structural components:
1. Cells organised into functional units 2. The extracellular matrix 3. Scaffolding architecture
Tissue engineering-a biomaterial perspective
Nature Nanotechnology 6, 13–22 (2011)
Tissue engineering-scaffold concept
• Biodegradable• Fast spread on wet (wound) surface• Adequate working time• Adequate bonding strength• Hemostasis• Biocompatible• Easy cell penetration, distribution,
proliferation• Permeability of culture medium• In vivo vascularization (once implanted)• Maintenance of cell phenotypes• Adequate mechanical properties• Controlled biodegradation• Ease of fabrication
Requirements of Biomaterials as Tissue engineering Scaffold.
Advanced Drug Delivery Reviews, Volume 65, Issue 4, 2013, 581 - 603
Metals
Biocomposite
Ceramics
Polymers
BIOMATERIALS
Orthopedic screws/fixation
Dental Implants
Dental Implants
Heart valves
Bone replacements
Biosensors
Implantable Microelectrodes
Skin/cartilageDrug Delivery
DevicesOcular implants
Biomaterials –Classical sources
Natural biomaterialsProteins• Silk• Keratin• Collagen• Gelatin• Fibronogen• Elastin• Actin• MyosinPolysaccharides• Cellulose• Amylose• Dextron• Chitin• GlysaminoglyconsPoly neucleotites• DNA• RNA
Synthetic biomaterials• PMMA-Poly(methyl methacrylate) • PVC- polyvinyl chloride• PLA/PGA- Poly lactic acid/poly glycolic acid• PE-Polyethylene• PP-Poly propylene• PA-Poly amides• PTFE -Polytetrafluoroethylene• PET-Polyethylene terephthalate• PUR-Polyurethane• Silicones
Advantages• Easy to make complicated
items• Tailorable physical &
mechanical properties• Surface modification• Immobilize cell etc.• Biodegradable
Disadvatages• Leachable compounds• Absorb water & proteins etc.• Surface contamination• Wear & breakdown• Biodegradation• Difficult to sterilize
Polymeric Biomaterials
Chem. Soc. Rev., 2009,38, 1139-1151
Polymeric Biomaterials-Tissue engineering
Scaffolds
Advantages • High compression strength• Wear & corrosion resistance• Can be highly polished• Bioactive/inert
Disadvantage • High modulus (mismatched with
bone)• Low strength in tension• Low fracture toughness• Difficult to fabricate
• Alumina• Zirconia (partially stabilized)• Silicate glass• Calcium phosphate (apatite)• Calcium carbonate
Bioceramic-biomaterials
• Stainless steel (316L)
• Co-Cr alloys• Ti6Al4V• Au-Ag-Cu-Pd alloys• Amalgam
(AgSnCuZnHg)• Ni-Ti• Titanium
Advantages.• High strength• Fatigue resistance• Wear resistance• Easy fabrication• Easy to sterilize• Shape memoryDisadvantages• High moduls• Corrosion• Metal ion sensitivity and toxicity• Metallic looking
Metallic-biomaterials
• Mechanical and chemicals properties• No undersirable biological effects carcinogenic, toxic, allergenic or
immunogenic• Possible to process, fabricate and sterilize with a godd reproducibility• Acceptable cost/benefit ratio
General Criteria for materials selection
Material Properties• Compresssive strength• Tensile strength• Bending strength• E-Modulus• Coefficient of thermal expansion• Coefficient of thermal coductivity
• Surface tension• Hardness and density• Hydrophobic/philic• Water sorption/solubility• Surface friction• Creep• Bonding properties
Deterioration of Biomaterials• Corrossion• Degradation• Calcification• Mechanical loading• Combined
Valve cells Collagen scaffold of heart valve
Heart valve post- implantation
Heart valve tissue engineering
The promise of Biomaterials
Intraocular Lens
Vascular Grafts
Substitute Heart Valves
Artificial Hip Joints
Matrix-based ACI using a collagen type I hydrogel..(A) Articular cartilage defect (3 × 2 cm) at the medial femoral condyle in a 31-year old male. (B) Debridement was performed down to the subchondral bone and the shape of the chondrocyte-laden colla...
Advanced Drug Delivery Reviews, Volume 65, Issue 4, 2013, 581 - 603
Collagen material for articular cartilage defect
• Physical and mechanical • Biological• In vitro assessment• in vivo assessment• Functional assessment• Clincal assessment
Testing method
• Cell culture, cytotoxicity (Mouse L929 cell line)
• Hemolysis (rabbit or human blood)• Mutagenicity (Ames test)• Systemic injection, acute toxicity
(Mouse)• Sensitization (Guinea pig)• Pyrogenicity (Rabbit)• Intramuscular implnatation (Rat,
rabbit)• Blood compatibility• Long-term implatation.
Testing of Biomaterials
General Problems with Biomaterials
• Acute toxicity (cytotoxicity) arsenic• Sub chronic/chronic Pb• Sensitization Ni, Cu• Genotoxicity• Carcinogenicity• Reproductive &/or developmental
Pb• Neurotoxicity• Immunotoxicity• Pyrogen, endotoxins
• Amalgam• Dental composite• Ceramics• Other metals
General criteria for tooth filling materials• Non-irritation to pulp and gingival • Low systemic toxicity• Cariostatic• Bonding to tooth substance without marginal leakage (20 u)• Not dissolved or erode in saliva• Mechanical strength, wear resistance, modules matching.• Good aesthetic properties• Thermal propertiesy (expansion & conductivity)• Minimal dimensional changes on setting and adequate working time and radio opacity
Tooth fillings materials
• Cell matrices for 3-D growth and tissue reconstruction
• Biosensors, Biomimetic , and smart devices• Controlled Drug Delivery/ Targeted delivery• Biohybrid organs and Cell immunoisolation• New biomaterials - bioactive, biodegradable,
inorganic• New processing techniques
Advances in Biomaterials Technology
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