Electrospray interface digestion

A microfluidic system was described by Wang and coworkers [108] in which an electrospray interface to MS was integrated to a CE channel and a protein digestion... 

Wang C., Oleschuk R., Ouchen F., Li J., Thibault R, and Harrison D.J. (2000), Integration of immobilized trypsin bead beds for protein digestion within a micro-fluidic chip incorporating capillary electrophoresis separations and an electrospray mass spectrometry interface, Rapid Commun. Mass Spectrom. 14(15), 1377-1383. 

Electrospray ionization and MALDI represent major advances in the application of mass spectrometry to analysis of biomolecules. Although in many cases the two techniques are able to provide the same information, quite frequently they are complementary. For a variety of reasons, some samples are more successfully analyzed by MALDI and other by ESI. Thus, it is highly beneficial to have access to both types of instrument for characterization of synthetic peptides. In ESI-MS, the samples are introduced in solution at flow rates from less than 1 tL/min up to 1 mL/min, depending on the design of the ESI interface. Pure samples and simple mixtures are often analyzed by direct infusion more complex mixtures (such as proteolytic digests) generally require either on-line or off-line HPLC fractionation prior to MS analysis. 

---