>> Research Projects >> Scaffolds Fabrication

The other major line of our research is scaffolding technology development. Several key technologies are available in our group, including phase inversion (Top Fig), leaching plus biomimetic modification (Fig 2), electrospinning (Fig. 3), photolithography plus ion etching, laser microfabrication, rotating casting, etc.  These technologies can be widely used in many tissue engineering applications.

One direction is the design and fabrication of 3-D scaffolds for tissue engineering and regenerative medicine utilizing both non-degradable and biodegradable biomaterials and biological materials to mimic the natural environment where cells normally reside, and promote tissue formation from cells both in vitro and in vivo by arranging cells/tissue in a desirable 3-D configuration and presenting molecular signals in an appropriate spatial and temporal fashion.  For example, Scaffold containing unidirectional aligned honeycomb channels in sizes close to the cellular range can be fabricated using phase inversion, leaching or laser microfabrication approaches for nerve guidance, muscle, or long bone tissue engineering applications. Such structure mimics the Bands of Bungner in peripheral nerve and offers strong unidirectional guidance effect on the regenerating axons. Such structure also closely mimic the histological structure of skeletal or cardiac muscle tissue and cortical bone tissue.

Another direction in the scaffold construction is the bioactive, semi-permeable hollow fiber membranes (HFMs, Visit Bioactive HFM Page). which are widely used in cell-encapsulating devices, nerve guidance channels, microdialysis probes, and bioreactors. Recently, my group had fabricated both non-degradable and biodegradable hollow fiber membranes loaded with bioactive molecules. Therapeutic agents/growth factors can be incorporated during the fabrication process or during polymer synthesis to enhance the tissue regeneration. 

In order to improve the guidance potential of a nerve entubulation bridging device, highly aligned textures were formed on the inner surface of semipermeable hollow fiber membranes (HFMs) during the wet phase inversion process (Visit Textured HFMs page).

In addition, our group also developed highly elastic HFMs for engineering tubular structure in the body (Visit Elastic HFMs page).

Electrospinning is currently used in my lab to fabricate 1) branching tubular network (prepare for patent), 2) drug loaded nonwoven scaffold for wound dressing applications, 3) wrinkled/waved collagen nanofibers embedded in elastic composite tubular structure to mimic the mechanical properties of natural blood vessels (patent pending).

Two types of microfabication techniques are used to develop scaffolds with aligned texture for tissue engineering. One is the combination of photolithography and ion etching to fabricate aligned texture for guided tissue engineering, such as axonal guidance, cardiac patch engineering. The other is Eximer laser based microfabication, which can be used to fabricate highly align honeycomb scaffold for guided tissue engineering, and also to fabricate pores on elastic hollow fiber membrane for lung unit tissue engineering  (Visit Microfabrication Webpage.