Microstereolithography (μSL) technology can fabricate three-dimensional (3D) tissue
engineered scaffolds with controlled biochemical and mechanical micro-architectures. A
μSL system for tissue engineering was developed using a Digital Micromirror Device
(DMDTM) for dynamic pattern generation and an ultraviolet (UV) lamp filtered at 365 nm for
crosslinking the photoreactive polymer solution. The μSL system was designed with x-y
resolution of ~2 μm and a vertical (z) resolution of ~1 μm. To demonstrate the use of μSL in
tissue engineering, poly(propylene fumarate) (PPF) was synthesized with a molecular weight
of ~1200 Da. The viscosity of the PPF was reduced to ~150 cP (at 50 o
C) by mixing with
diethyl fumarate (DEF) in the ratio of 7:3 (w/w). Finally, ~2 % (w/w) of (bis(2,4,6-
trimethylbenzoyl) phenylphosphine oxide (BAPO) was added to the solution to serve as a
photoinitiator. Cure depth experiments were performed to determine the curing
characteristics of the synthesized PPF, and the resulting system and photopolymer were used
to construct a variety of 3D porous scaffolds with interconnected pores between 100 and 150
μm and a micro-needle array with height of ~800 μm and individual tip diameters of ~20 μm.
SEM and microscope images of the micro-architectures illustrate that the developed μSL
system is a promising technology for producing biodegradable and biocompatible
microstructures.Mechanical Engineerin
