title: Alternating current electrokinetics enhanced in situ capacitive immunoassay.
abstract: A rapid in situ capacitive immunoassay is presented herein. Conventional immunoassay typically relies on diffusion for transport of analytes in many cases causing long detection time and lack of sensitivity. By integrating alternating current electrokinetics (ACEK) and impedance sensing, this work provides a rapid in situ capacitive affinity biosensing. ACEK induces both fluid flow and particle motion, conveying target molecules toward electrodes immobilized with probes, resulting in rapid enrichment of target molecules and a capacitance change at the ''electrode-fluid'' interface. The benefit of ACEK enhanced immunoassay was demonstrated using the antigen and antibody from Johne's disease (JD) as an example. To clarify the importance of DEP and ACET effects for binding reaction, two different electrode pattern designs for capacitive immunoassay are studied. The asymmetric array and symmetric electrodes exhibit very similar response at lower electric field due to DEP effects, while asymmetric array has remarkable higher response at high-electric field because the convection becomes more important at high field. The disease positive and negative serum samples are distinguished in few minutes.
authors.affiliation: School of Mechatronics Engineering, Harbin Institute of Technology, Harbin, China; Department of Electrical Engineering and Computer Science, The University of Tennessee, Knoxville, TN, USA; School of Mechanical Engineering, Hebei University of Technology, Tianjin, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Li
authors.forename: Yukun
authors.initials: Y
authors.lastname: Ren
authors.forename: Haochen
authors.initials: H
authors.lastname: Cui
authors.forename: Quan
authors.initials: Q
authors.lastname: Yuan
authors.forename: Jie
authors.initials: J
authors.lastname: Wu
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Eda
authors.forename: Hongyuan
authors.initials: H
authors.lastname: Jiang
mesh_terms: D001774:Blood Chemical Analysis; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D004867:Equipment Design; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D046228:Microarray Analysis
keywords: AC electrothermal effect; Capacitive affinity sensing dielectrophoresis; Immunosensor