Ultrasonic-trap-enhanced selectivity in capillary electrophoresis

• We combine ultrasonic trapping and capillary electrophoresis (CE) with the goal to detect ultra-low concentrations of proteins via size-selective separation and enrichment of antibody-coated latex spheres. An 8.5 MHz standing ultrasonic wave is longitudinally coupled into the sub-100-muM diam capillary of the CE system. Competition between acoustic and viscous forces result in inflow separation of mum-diam spheres according to their size. Experiments separating 2.8- and 2.1-mum-diam fluorescent latex particles, which model a protein-specific immunocomplex/free particle mixture, indicate a potential improvement of the concentration limit of detection of 10(4) compared to current CE systems. Theoretical calculations show room for further improvement.

Nyckelord

ultrasonic trapping

particle separation

capillary electrophoresis

concentration limit of detection

microparticles

fluorescence

droplet

protein

wave

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ref (ämneskategori)

art (ämneskategori)