Bio-Based Materials in MedicineBio-Based Materials in Medicine

Johnathan Marks and Blake MorellJohnathan Marks and Blake Morell

SummarySummary

• Background

• Motivation

• Basic Principles

• Examples

• Conclusion

• Further Research

http://www.accesslifenethealth.org/

BackgroundBackground

• Bio-based materials– Biomass derived (Type 1)

• Polysaccharides and proteins

– Bio-monomer derived (Type 2)• Polylactic acid (PLA)

– Microorganism derived (Type 3)• Polyhydrocyalkanoate (PHA), xanthan, and

bacterial cellulose

BackgroundBackground

Weber, C. J., "Biobased Packaging Materials for the Food Industry: Status and Perspectives"

MotivationMotivation

• Prevalence of chronic conditions– Cardiovascular disease– Diabetes– Arthritis– Neurodegenerative disease

• Biopolymers ideal for new biomedical devices– Effectively interface with

human cells and tissue– Properties can be easily tuned

to match properties of target tissues http://www.ecareer.com/healthcare-jobs-demand-factor/

Basic PrinciplesBasic Principles

• Materials• Engineering biology• Processing• Scale-up

http://www.arnoff.com/commercial-moving-services/medical-equipment-laboratory-moving.aspx http://www.prime-water.com/web/index.php?

option=com_content&view=article&id=58&lang=en

Biomedical Material SpecificationsBiomedical Material Specifications

• Biocompatibility

• Performance requirements

• Non-toxic

• Non-inflammatory

• Shelf stability

• Usability

Ratner, B. D., et al., "Biomaterials Science: An Introduction to Materials in Medicine"

Carbohydrates for Wound ClosureCarbohydrates for Wound Closure

• Current problem: leakage from internal wounds– Need tissue adhesives

• Synthetic chemicals– Cyanoacrylates or

glutaraldehyde• Poor biocompatibility and

performance problems

• Hydrogel tissue adhesives based on polysaccharide dextran

http://medtechinsider.com/archives/27309

http://www.asme.org/kb/news---articles/

Carbohydrates for Wound ClosureCarbohydrates for Wound Closure

• Dextran - polysaccharide of D-glucose units– Manufactured by bacteria

• Reaction: dextran aldehyde with multi-arm polyethylene glycol-amines makes cross-linked hydrogel

• Benefits: free of blood products, non-cytotoxic, capable of difficult incisions

Bhatia, S. K., "Bio-Base Materials Step into the Operating Room"

Soy for Bone RepairSoy for Bone Repair

• Current problem: no bone reconstruction materials that meet requirements

• Soybeans: contain bioactive phytoestrogens– Induce differentiation of osteoblasts

Santin, M. et al., "Soybean-based Biomaterials: Preparation, Properties and Tissue Regeneration Potential"

Soy for Bone RepairSoy for Bone Repair

• Synthesis - processed into films, membranes, porous scaffolds, and granules

• Benefits: ductility, bioactive, injectable

http://www.sjlshots.com/tag/soybeans/

Santin, M. et al., "Soybean-based Biomaterials: Preparation, Properties and Tissue Regeneration Potential"

Silk for Scaffolding TissuesSilk for Scaffolding Tissues

• Silk fibers are superior to synthetic high-performance fiber– Alanine - and glycine-

rich protein consisting of repeating crystalline and amorphous regions

– Good biocompatibility and biodegradability

• Silk scaffolds used to engineer cartilage, vascular, bone, and ligament tissues Liu, H., et al., "Electrospun sulfated silk fibroin nanofibrous scaffolds for vascular tissue

engineering"

Bone TissueBone Tissue

• Scaffold modified with RGD – Support cellular adhesion

• Mesenchymal stem cells– From bone marrow– Differentiate into bone,

cartilage, or muscle

• Combine to form organized bone-like structure Mandal, B. B., et al., "High-strength silk protein scaffolds for bone

repair"

Vascular TissueVascular Tissue

• Silk nanofibers manufactured by aqueous-based electrospinning

• Support the growth of aortic endothelial cells and coronary artery smooth-muscle cells

• Can be formed into tubes that withstand human blood pressures

http://www.flickr.com/photos/7357040@N05/424741496/in/set-72157600005536436/

Growth of Vascular TissueGrowth of Vascular Tissue

Liu, H., et al., "Electrospun sulfated silk fibroin nanofibrous scaffolds for vascular tissue engineering"

ConclusionConclusion

• Search for materials with optimum compatibility with the human body

• Naturally sourced biopolymers are ideal for new biomedical devices

• Successful applications in wound closure, tissue repair, and tissue regeneration

• Field of bio-based materials for biomedical implants still developing

Further ResearchFurther Research

• Detailed models of cellular proliferation and tissue repair

• Mechanistic study of interactions between biopolymers with cells, tissues, and organs

• Synthesize polymers from monomers obtained from agricultural resources

• Polymers derived from microbial production

• Reliable, cost-effective, scaled-up production

ReferencesReferences

Bhatia, S. K., "Bio-Based Materials Step into the Operating Room," American Institute of Chemical Engineers, pp. 49-53 (Sept. 2012).

Weber, C. J., "Biobased Packaging Materials for the Food Industry: Status and Perspectives," European Union Directorate 12, Royal Veterinary and Agricultural Univ., Frederiksberg, Denmark (2000).

Santin, M., and L. Ambrosio, "Soybean-Based Biomaterials: Preparation, Properties and Tissue Regenertation Potential," Expert Reviews in Medical Devices, 5 (3), pp. 349-358 (May 2008).

Liu, H., et al., "Electrospun sulfated silk fibroin nanofibrous scaffolds for vascular tissue engineering," Biomaterials, 32 (15), pp. 3784-3793 (May 2011).

Mandal, B. B., et al., "High-strength silk protein scaffolds for bone repair," Proceedings of the National Academy of Sciences of the United States of America, (May 2012).

Questions?Questions?