| Synthetic biodegradable polymers have been extensively studied for their use in tissue engineering and drug delivery. Recently, the micro-fabrication of biodegradable polymers has drawn much attention, since it allows creating cellular scale features which have been known to influence cell growth. Micro-fabricated biodegradable polymers have also been used as drug delivery carriers. The micro-fabricated drug delivery devices can deliver the precise amount of drugs at pre-determined times as required for different types of diseases. However, there has been no systematic investigation into the methods to micro-fabricate biodegradable polymers. Most of the previous investigations either were limited to two dimensional micro-patterning of biodegradable polymers or have not explored different types of synthetic biodegradable polymers which vary in their physical and chemical properties. This dissertation explores micro-molding and joining methods for various synthetic biodegradable polymers to develop basic technologies that will allow us to create any three dimensional micro-structured device. The developed technologies are exemplified as micro-fabricated tissue scaffolds and drug delivery devices. The example micro-fabricated tissue scaffolds contain complex micro-cavities for cell growth and micro-fluidic connections for cell communication and supply of nutrient and oxygen. A novel concept of programmed drug delivery devices of biodegradable polymers is suggested and demonstrated. Control of drug release is achieved by micro-geometry in sample devices. In vitro study shows that various release profiles are obtained from the devices. Furthermore, models for a finite element method are provided for the analysis and characterization of micro-fabricated drug delivery devices. |
