Smart Surfaces: Use of Electrokinetics for Selective Modulation of Biomolecular Affinities


With the aid of negative dielectrophoresis (nDEP) force in conjunction with shear force and at an optimal sodium hydroxide (NaOH) concentration we demonstrated a switch-like functionality to elute immuno-bound beads from the surface. At an optimal flow rate and NaOH concentration, nDEP turned on results in bead detachment, whereas when nDEP is off, the beads remain attached. This platform offers the potential for performing a bead-based multiplexed immunoassay where in a single channel various regions are immobilized with a different antibody, each targeting a different antigen. As a proof of concept we demonstrated the ability of nDEP to provide this switching behavior in a singleplex assay for the interactions that were in the same order of magnitude in strength as typical antibody-antigen interactions.

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This work was supported by the National Institutes of Health grant PO1HG000205.

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Correspondence to Sam Emaminejad.

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Emaminejad, S., Javanmard, M., Dutton, R.W. et al. Smart Surfaces: Use of Electrokinetics for Selective Modulation of Biomolecular Affinities. MRS Online Proceedings Library 1415, 133–138 (2012).

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