This grant provides funding to study fundamental phenomena of laser-gas-polymer interaction, with a goal to develop an innovative fabrication process for biochip devices that will enable high-throughput, organotypic cell-based diagnostics. The proposed research combines the processing capability of nano-/femtosecond lasers and a solvent-free gas foaming technique to create a large array of miniaturized three-dimensional tissue engineering scaffolds on a polymer chip. While extremely localized heat will be generated to create the porous structure, precision laser machining will be employed to shape the scaffolds and engrave microfluidic channels. Both theoretical and experimental studies will be conducted to understand the mechanisms of the proposed process, including laser heating, ablation, and bubble nucleation and growth in gas impregnated polymer. A sequentially coupled numerical model will be developed to study the nonlinear effects in the laser heating and bubble formation process. A biocompatibility study of the fabricated device will also be conducted.
If successful, the results of this research will lead to a novel manufacturing process to create organotypic microarrays that could offer a completely ethical alternative to using animals and humans in drug screening. Current two-dimensional cell culture conditions yield monolayers that are poor mimics of the in vivo cellular microenvironment. The fabrication process developed in this research will enable realistic three-dimensional tissue analogs built into a large array for high throughput, parallel interrogation of drug candidates. The proposed research explores complex interaction among laser, polymer, and gas bubbles. Findings of this research will add to the scientific knowledge base in laser material processing, a strategic area in advanced manufacturing that helps maintain the US leading position in the world. The proposed research will not only stimulate scientific discovery, but also provide opportunities for student training and technology transfer.