Many chemical analysis systems require extensive measuring, mixing, and separation/detection operations before data can be collected. Some of these tests, such as hospital tests for bacterial infections, would greatly benefit by an increased processing speed; all would benefit by a decrease in labor and materials costs. In recent years, a number of companies have integrated all the required steps for a particular test into a simple format (home pregnancy kits are a good example). Most of these formats, though, are far from robust and can usually only handle "yes/no" results.

We are constructing miniaturized chemical analysis systems using silicon fabrication techniques. The devices consist of micron-scale reaction, separation, and detection systems connected by a series of micromachined channels. Samples are injected into these devices and then moved between components by a variety of techniques including surface tension control and hydrophobic/hydrophilic patches. Reaction chambers in these devices can be used for selective amplification or digestion of reactants. The products of these reactions can then be analyzed using separation techniques such as simple gel electrophoresis. Integration of all these steps produces a micron-scale device that can act as an intelligent sensor. Currently, our main focus is the analysis and sequencing of DNA although the techniques used can be applied to a variety of chemical analysis systems.

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