1. Nanotechnology in Cell and Tissue Engineering
Gregory Damhorst
BIOE 506

2. Nature Nanotechnology, January 2011
Overview
Nature Nanotechnology, January 2011
Tissue Engineering Basics Nanotechnology Methods Design Examples Nanomaterials Nanodevices

3. Tissue Engineering basics
Part I: Understanding Tissue
Tissue Engineering basics

4. Tissue Engineering Basics
Motivation: repair of damaged tissues and organs
Used to think that the matrix simply defined tissue boundaries
The key is in the ECM
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

5. Tissue Engineering Basics
EXTRA- CELLULAR MATRIX

6. Tissue Engineering Basics
Extracellular Matrix

7. Tissue Engineering Basics
Extracellular Matrix
Protein fibres (collagen, elastin)
Adhesive protein (laminin, fibronectin)
Polysaccharides (hyaluronic acid, heparan sulphate)
Cell adhesion (integrin, cadherin)
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

8. Tissue Engineering Basics
Extracellular Matrix
The key is in the ECM
Topography
Mechanical Properties
Growth Factor Concentration
ECM Molecules
The ECM promotes a unique microenvironment that fosters tissue organization
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

9. Tissue Engineering Basics
Extracellular Matrix
The key is in the ECM
Topography
Mechanical Properties
Growth Factor Concentration
ECM Molecules
The ECM promotes a unique microenvironment that fosters tissue organization
control the ECM -> control the tissue
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

10. Tissue Engineering Basics
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

11. Nanotechnology methods
Part II: Fabricating the ECM
Nanotechnology methods

12. Nanotechnology Methods
Electrospinning
Simple
Usually at upper-range of natural nm fiber diameter
Self Assembly
Smaller fibers and pore sizes
Can include functional motifs – mechanical and instructive matrix support
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

13. Nanotechnology Methods
Electrospinning
Polymer solution charged and fed into electric field
Carrier solution evaporates and fibrils are deposited on substrate
Barnes, C.P. et al. Nanofiber technology: Designing the next generation of tissue engineering scaffolds. Adv. Drug. Deliv. Rev. 2007

14. Nanotechnology Methods
Self-assembly
Zhang, S. Fabrication of novel biomaterials through molecular self-assembly. Nature Biotechnol

15. Nanotechnology Methods
Self-assembly:
Ionic Self-complementary peptide
Peptide of 16 AA
Alternating polar/nonpolar
Form stable β-strands and β-sheets
Form nanofibers by hydrophobicity
Matrices with high H2O content
Zhang, S. Fabrication of novel biomaterials through molecular self-assembly. Nature Biotechnol

16. Nanotechnology Methods
Self-assembly:
Surfactant-type peptide
Charged head group and nonpolar tail
Form nanotubes and nanovesicles
Form interconnected network
Similar to carbon nanotube behavior
Zhang, S. Fabrication of novel biomaterials through molecular self-assembly. Nature Biotechnol

17. Nanotechnology Methods
Self-assembly:
Surface nanocoating peptide
Three regions:
Anchor
Linker
Functional Head
Can be used in inkjet printer
Zhang, S. Fabrication of novel biomaterials through molecular self-assembly. Nature Biotechnol

18. Nanotechnology Methods
Self-assembly:
Molecular switch peptide
Strong dipoles
Conformation changes from α<->β
Could be coupled with metal nanocrystals
Zhang, S. Fabrication of novel biomaterials through molecular self-assembly. Nature Biotechnol

19. Nanotechnology Methods
Non-fibrous ECM components
Adhesion proteins
Growth factors
Topography
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology

20. Nanotechnology Methods
Adhesion Proteins
Matrix modified with adhesion proteins
Unmodified scaffold
Spreading and attaching to matrix
Only cell-cell adhesion
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Re’em, T. The effect of immobilized RGD peptide in macroporous alginate scaffolds on TGFbeta1-induced
chondrogenesis of human mesenchymal stem cells. Biomaterials

21. Nanotechnology Methods
Growth Factors
bFGF – Basic Fibroblast Growth Factor
Promotes angiogenesis
bFGF bound to scaffold
bFGF adsorbed to scaffold
bFGF absent
Freeman, I. The effect of sulfation of alginate hydrogels on the specific binding and controlled release of heparin-binding proteins. Biomaterials

22. Nanotechnology Methods
Growth Factors
bFGF – Basic Fibroblast Growth Factor
Promotes angiogenesis
bFGF bound to scaffold
bFGF adsorbed to scaffold
bFGF absent
Freeman, I. The effect of sulfation of alginate hydrogels on the specific binding and controlled release of heparin-binding proteins. Biomaterials

23. Nanotechnology Methods
Topography
Endothelial Cells
Flat topography
Grooved topography
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Teixeira, AI. Epithelial contact guidance on well-defined micro- and nanostructured substrates. J. Cell. Sci

24. Part III: Designing a Scaffold
Design Examples

25. Cardiomyocytes ECM forces cardiomyocytes to couple mechanically
Nanogrooved surface can force cell alignment in same way
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Kim, DH. Nanoscale cues regulate the structure and function of macroscopic cardiac tissue constructs. PNAS

26. Epithelial Cells
Epithelial cells are polarized and adhere to other cells
Nanofibres modified with surface molecules can promote these effects
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Feng, ZQ. The effect of nanofibrous galactosylated chitosan scaffolds on the formation of rat primary hepatocyte aggregates and the maintenance of liver function. Biomaterials

27. Bone Osteoblasts influenced by bone matrix
Nanostructures used to enhance osteogenesis
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Roohani-Esfahani, SI. The influence hydoxyapatite nanoparticle shape and size on the properties of biphasic calcium phosphate scaffolds coarted with hydroxyapatite-PCL composites. Biomaterials

28. Part IV: Enhancing the Engineering Matrix
Nanomaterials

29. Nanomaterials Carbon Nanotubes
CNT sponges increase conductivity of matrix
Also use to increase tensile strength
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Wang, S. F., Shen, L., Zhang, W. D. & Tong, Y. J. Preparation and mechanical properties of chitosan/carbon nanotubes composites. Biomacromolecules. 2005
Gui, X. et al. Soft, highly conductive nanotube sponges and composites with controlled compressibility.ACS Nano

30. Nanomaterials Nanotitanate Wires
Specially fabricated wires to promote cell-matrix adhesion
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Wu, S. L. et al. A biomimetic hierarchical scaffold: natural growth of nanotitanates on three-dimensional microporous Ti-based metals. Nano Lett. 2008

31. Nanomaterials Nanospheres Control the release of growth factors
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Zhang, SF. Nanoparticulate systems for growth factor delivery. Pharm

32. Nanomaterials Gold Nanowires
Control wire with electrophoresis and dielectrophoresis
Control localization of biomolecules
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Fan, D. Subcellular-resolution delivery of a cytokine through precisely manipulated nanowires. Nature Nanotechnology

33. Nanomaterials Phage, magnetic iron oxide and gold nanoparticles
Manipulate geometry of cell mass with 3D structure
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Souza, G. Three-dimensional tissue culture based on magnetic cell levitation. Nature Nanotechnology

34. Part V: Monitoring Tissue Development
NANODEVICES

35. Nanodevices Electrical Recording
Penetrates cell membrane, measure intracellular signals
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Tian, B. Three dimensional, flexible nanoscale field-effect transistors as localized bioprobes. Science

36. Nanodevices Biosensors
Optical biosensor – photoluminescence differs by presence of drug or reactive species
Dvir, Tal, et al. Nanotechnological strategies for engineering complex tissues. Nature Nanotechnology
Heller, DA. Multimodal optical sensing and analyte specificity using single-walled carbon nanotubes. Nature Nanotech

37. Nature Nanotechnology, January 2011
Summary
Nature Nanotechnology, January 2011
Tissue Engineering Basics Nanotechnology Methods Design Examples Nanomaterials Nanodevices

38. The End
Questions