Chemical analysis and electrophoresis systems integrated on glass and silicon chips

The feasibility of miniaturizing a chemical analysis system on a planar substrate has been demonstrated for a system utilizing electrokinetic phenomenon for sample separation and solvent pumping. Using micromachining techniques, a manifold of capillary channels has been fabricated in a planar glass substrate. Separation of components of a mixture using electrophoresis has been achieved within the channels using applied voltages of up to 10 kV. The separation efficiency was in agreement with theory, indicating no interactions between the analyte and the glass walls. Solvent flow could be directed along a specified capillary by application of appropriate voltages, so that valveless switching of fluid flow between capillaries could be achieved.<>