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

Area of Science:

• Biomolecular analysis
• Microfluidics
• Analytical chemistry

Background:

• Electrophoretic separation in microchannels offers rapid biomolecule analysis.
• Pressurized laminar flow can reduce separation efficiency in microchannels.

Purpose of the Study:

• To develop a novel method for enhancing electrophoretic separation efficiency in microchannels.
• To enable rapid formation and removal of a solid hydrogel within microchannels using an electric field.

Main Methods:

• Utilized an electric field to induce the formation and removal of a chitosan/β-glycerol phosphate (CS/β-GP) hydrogel in microchips.
• Employed a cross-type microchip for precise hydrogel formation (15 s at 2000 V) in the separation channel.
• Achieved peptide and protein separation using the in-situ formed hydrogel.

Main Results:

• Demonstrated highly efficient separation of peptides and proteins.
• Attained theoretical plate numbers of 0.6 to 1.5 × 10^6/m for proteins within 120 s.
• Showcased swift hydrogel removal using an electric field.

Conclusions:

• The electric field-induced CS/β-GP hydrogel system significantly improves electrophoretic separation efficiency in microchannels.
• This technique allows for rapid, on-demand hydrogel formation and removal, suitable for standard microchip electrophoresis devices.
• The method provides a versatile and efficient approach for fast biomolecule analysis.