Disclosed are microfluidic devices and methods for performing analyses which, in a preferred embodiment, involve sample filtration, solid phase extraction for enrichment of target analytes and separation of target analytes via open channel electrochromatography. Small sample volumes of mixed analytes are resolvable in less than one minute using the disclosed devices and methods.
 This invention was made with Government support under Contract No. DE-AC05-00OR22725 awarded to UT-Battelle, LLC, by the U.S. Department of Energy. The Government has certain rights in this invention.