A Microfabricated Fluidic Reaction and Separation System for Integrated DNA Analysis

In recent years, there has been increasing interest in developing a complete, highvolume, DNA analysis system using microfabrication techniques. Such analysis systems require components for injection, pumping, mixing, reaction, separation and detection. Over the past decade, many researchers have demonstrated that micromachined fluidic devices are capable of performing many of the required functions of chemical analysis. In addition, coupling the individual analysis steps onto a single microfabricated device significantly simplifies the process, minimizes human intervention, reduces the risk of contamination, and could lead to the realization of hand-held ‘Lab-on-a-chip’ devices. We are presently developing a fluidic handling, reaction and separation system for integrated DNA analysis. The current generation of our system contains an injection system based on selective hydrophobic patterning, air driven/thermocapillary fluid pump, a temperature controlled reaction chamber and a high-resolution electrophoresis and detection system. Since all the components are fabricated on the same wafer and use a similar channel design, the entire device could potentially function as one unit. We have successfully used these devices to perform a variety of DNA analysis techniques including constant temperature amplification using Strand Displacement Amplification (SDA) and gel-electrophoresis.