>> Research Projects >> Microfabrication

1.  Photolithography plus ion etching

Highly aligned textures with well controlled size can be fabricated on silicon wafers using a combined techniques of photolithography and dry ion etching. Uniform size grooves can be formed on silicon wafer as shown figure 1, we then transfer the texture onto biodegradable polymer surface using solvent casting method. Textured surface was used to 1) align cardiomyocytes to form aligned cell sheet for cardiac patch tissue engineering, and 2) examine the ability of human umbilical cord blood stem cell derived neurons response to texture as shown in figure 2.

Figure 1: Highly aligned texture developed using a combination of  photolithography and dry ion etching.


Figure 2: Response of adult stem cell derived “young” specialized cells to aligned texture on the scaffold surface. Red color is neurofilament staining for neurons.

2. Laser-based 3-D microfabrication

An eximer laser (UV laser 150-193 nm) based microfabrication instrument has been setup very  recently for novel scaffold  fabrication. We are using this technology to precisely fabricate micro-features on the scaffolds. For example, we are studying the optimal hole sizes fabricated on elastic hollow fiber membranes for the formation of micro-vascular branches and lung alveoli structures. The other example application is highly organized scaffold fabrication as schematically shown below. This type of scaffolds will useful for engineering 3-D cardiac muscle, skeletal muscle, and neural tissues.