Reducing immunoassay incubation times with substrate rotation

ANYL 106

Jeremy D. Driskell, driskell@iastate.edu1, Jill Uhlenkamp1, Robert J. Lipert, blipert@ameslab.gov2, and Marc D. Porter, mporter@porter1.ameslab.gov3. (1) Department of Chemistry, Iowa State University, Ames, IA 50011, (2) Institute for Combinatorial Discovery, USDOE-Ames Laboratory, Iowa State University, Ames, IA 50011, (3) Department of Chemistry and of Chemical and Biological Engineering, Institute for Combinatorial Discovery, Ames Laboratory-USDOE, Iowa State University, 42 Spedding Hall, Ames, IA 50011
Immunoassays are often limited by the long incubation times that are required for analyte and label binding. As an approach to overcome this weakness, we have explored the potential for reducing the incubation time by increasing antigen flux to the surface of a rotating solid phase. A surface-enhanced Raman scattering (SERS)-based sandwich immunoassay was developed, coupling antibody-antigen specificity with the ultra-high sensitivity of SERS readout. An antibody-coated capture substrate, capable of controlled rotation, was immersed in sample solution containing rabbit IgG which served as the model analyte. After capturing the IgG target, the substrates were immersed and rotated in an extrinsic Raman label (ERL) labeling solution. The effect of substrate rotation on both the antigen binding and the ERL labeling steps were investigated. Implementation of rotation resulted in the reduction of assay times from 24 hours to 30 minutes with an improvement in the limit of detection.
 

General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

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8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Analytical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006