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-small mu, Greekm diam capillary of the CE system. Competition between acoustic and viscous forces result in in-flow separation of small mu, Greekm-diam spheres according to their size. Experiments separating 2.8- and 2.1-small mu, Greekm-diam fluorescent latex particles, which model a protein-specific immunocomplex/free particle mixture, indicate a potential improvement of the concentration limit of detection of 104 compared to current CE systems. Theoretical calculations show room for further improvement.

Subject headings

NATURVETENSKAP  -- Kemi -- Analytisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Analytical Chemistry (hsv//eng)

Keyword

Ultrasonic trapping

Capillary electrophoresis

Particle separation

Concentration limit of detection

Publication and Content Type

art (subject category)

ref (subject category)