A microfabricated
silicon chip with a separation material, such as in situ prepared porous
polymer monoliths in its microchannels is disclosed. The
polymer monoliths are liquid-permeable and serve as microcolumns for liquid
chromatography, which are prepared by in situ
radical polymerization of a mixture containing vinyl monomers and solvents (porogen) in the microchannels. A method and
system are disclosed to generate one or more
electrospray plumes from one or more nozzles that provide an
ion intensity as measured by a
mass spectrometer that is approximately proportional to the number of
electrospray plumes formed for analyses contained within the fluid. A plurality of
electrospray devices can be used in the form of an array of miniaturized separate electrospray devices for the purpose of generating multiple electrospray plumes from multiple nozzles for the same fluid for analysis. This invention dramatically increases the sensitivity of microchip electrospray devices compared to prior disclosed systems and methods. The
silicon chip having the packed microchannels disclosed herein finds application in
coupling with
mass spectrometry for sample analysis. Also disclosed is a separation block having multiple through-substrate channels filled with a separation material such as
polymer monolith which can be stacked in multiple blocks for sequential two-dimensional
chromatographic separation and integrated with the electrospray device.