25a Large DNA Synthesis on a Chip with Oligonucleotide Mixtures by Solid Phase Pcr and Ligation Chain Reaction

Woonghee Lee1, Jean-Marie Rouillard2, and Erdogan Gulari2. (1) Biomedical Engineering, The University of Michigan Ann Arbor, 2300 Hayward St., 3074 H.H. Dow Building, Ann Arbor, MI 48109, (2) Chemical Engineering, The University of Michigan Ann Arbor, 2300 Hayward St., 3074 H.H. Dow Building, Ann Arbor, MI 48109

The conventional gene synthesis including PCR usually takes 2 weeks because of the separate executions of the different procedures. As compared with this conventional experiment, a microfluidic chip only requires 2 days to assemble large DNAs. In this project, our overall objective is to develop an integrated microfluidic system that will synthesize long genes of arbitrary sequence in high purity and cut the lead times and cost per base from the current values by at least one order of magnitude. This project consists of three parts: oligonucleotide synthesis, purification, and large DNA synthesis. After the oligonucleotide synthesis on a chip, the oligos are purified by hybridization on a complimentary chip. Large DNA segments are manufactured by ligation chain reaction (LCR) and amplified on a microfluidic chip by polymerase chain reaction (PCR). Gene synthesis in the microfluidic chip is a very fast high throughput process, and requires less experimental reagents and solvents due to the integration of all processes and its small reaction volume. This device can also minimize contamination and shorten the overall time of the experiment by simplifying the material handling procedures. In our current project we are focusing on

1. Optimal oligo designing and testing on a chip ligation reactor system capable of simultaneously producing tens of double stranded oligomers of length which has from 0.2 to 1kb. 2. Developing PCR on a chip to amplify the LCR products specifically 3. Developing a purification system to eliminate mismatch containing synthetic oligomers.