Electric Field-Driven On-Request Instant in Situ Formation/Removal of Solid Hydrogel within Microchannels for Efficient Electrophoretic Separation

摘要

Electrophoretic separation in short microchannels is a promising way for rapid analysis of biomolecules, but the pressurized laminar flow may compromise the separation efficiency. In this work, through an electric field, instant formation and removal of a solid chitosan/beta-glycerol phosphate (CS/beta-GP) hydrogel within microchannels of microchips were realized. In a typical cross-type microchip, the CS/beta-GP hydrogel was precisely formed in the separation microchannel within 15 s of the application of a voltage of 2000 V. Highly efficient separation of peptides and proteins was achieved, and theoretical plate numbers of 0.6 to 1.5 x 10(6)/m were attained for proteins in 120 s. The used hydrogel could be swiftly removed also with an electric field, and the whole procedure was achieved on a standard microchip electrophoresis device with no extra accessory or special operation required.