We have developed functional components for a comprehensive microfluidic system for proteomic analyses. This dissertation presents development of an electroomsotic pump for delivery of fluids to other microfluidic channels, a hydrodynamic flow restrictor for combining electrokinetic and hydrodynamic flow on a microfluidic chip-ESI-MS interface, and surface coatings to prevent analyte adsorption to microfluidic channels. A microfluidic chip ESI-MS interface with a novel voltage switching component is also developed for the separation of negative analytes at high pH, with positive ion mode ESI-MS detection of the analyte, converted to positive ions via a make-up solution induced pH change
