Comparison of separation modes for microchip electrophoresis of proteins

Abstract

Separation of a set of model proteins was tested on a microchip electrophoresis analytical platform capable of sample injection by two different electrokinetic mechanisms. A range of separation modes—microchip capillary zone electrophoresis, microchip micellar electrokinetic chromatography, and nanoparticle‐based sieving—was tested on glass and polydimethylsiloxane/glass microchips and with silica‐nanoparticle colloidal arrays. The model proteins calmodulin (18 kiloDalton), bovine serum albumin (66 kDa), and concanavalin (106 kDa) were labeled with Alexa Fluor 647 for laser‐induced fluorescence detection. The best separation and resolution were obtained in a silica‐nanoparticle colloidal array chip.