Biocompatible Microvascular Networks for Tissue Engineering

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ITG Forum Biocompatible Microvascular Networks
for Tissue Engineering
Taylor Simpson Autonomic Materials Group
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Outline

• Background
• Network manufacturing
• Current research at UIUC utilizing mvascular
  networks
• mvascular networks as tissue scaffolds
• Scaffold requirements
• Current technologies
• Substrate approach
• Deposition ink approach
• Conclusions/Future Work
• Questions

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Previous Work

• Robotic Controlled Deposition

• Substrate Infiltration

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Previous Work
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Key Issues for Tissue Scaffolds

• Requirements
• Fully connected, open pore system
• Controlled pore size and location to optimize
  pore function (to diffuse nutrients and gasses
  and remove waste)
• Multiple layers for large tissues
• Degree of porosity should balance mechanical
  needs of the scaffold

• Current Issues
• Lack of control over porosity- location and size
• mm scale
• square channels vs. cylindrical channels

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Current Technologies
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Manufacturing Process

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Biocompatible Substrate
Hydroxy ethylmethacrylate (HEMA) ethylene
glycol dimethacrylate (EGDMA)

• Utilize existing ink
• Biocompatible
• Infiltrate at room temperature
• Requires a surfactant
• Tough (flexible)

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Biocompatible Substrate
Micro-CT Images
Cone-beam reconstruct
Amira- Isosurface
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Biocompatible Substrate
Micro-CT Images
Amira- Projection View
Amira- Isosurface
Amira-
Voltex View
Amira- Isosurface
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Biocompatible/Biodegradable Deposition Inks
PEG (C2H4O)n
PCL (C6H10O2)n

• Advantages
• Biocompatible/biodegradable
• Tm 43-46 0C
• Tg -95- -15 0C (varying MW)
• Cheap
• Disadvantages
• Stiff
• Water soluble
• Short degradation time (min)

• Advantages
• Biocompatible/biodegradable
• Tm 59-64 0C
• Tg -60 0C
• Cheap
• Long degradation time (yrs)
• Disadvantages
• Stiff
• Low solubility
• Requires heat for extrusion

72 layer PEG network
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Conclusions/Future Work

• Shown ability to manufacture a biocompatible 3-D
  mvascular network
• Designate use
• Manufacture a mvascular PCL network
• Demonstrate manufacturability of PCL/PEG
  copolymer with predicted decomposition rate

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References
Acknowledgements
Professor Scott White Katie Toohey Rob
Sheperd Ben Grosser Dan Webber

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