MICROMACHINING OF CAPILLARY ELECTROPHORESIS INJECTORS AND SEPARATORS ON GLASS CHIPS AND EVALUATION OF FLOW AT CAPILLARY INTERSECTIONS

A capillary electrophoresis system with a sample injector has been int egrated on a 1 X 2 cm planar glass chip by use of micromachining techn iques. Separation of three amino acids was achieved in the device with in 4 s. A maximum of 6800 theoretical plates was obtained with 470 V b etween injection and detection points. Electric fields of 2500 V/cm an d power dissipation of 2.3 W/m did not result in Joule heating effects due to the thermal mass and conductivity of the glass chips. Leakage at channel intersection points was found to arise from convective as w ell as diffusion effects. Methods of device fabrication are presented.