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Surface plasmon enhanced diffraction for label-free biosensing.

Fang Yu·Shengjun Tian·Danfeng Yao·Wolfgang Knoll
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Abstract

Surface plasmon enhanced evanescent field at a (noble) metal/dielectric interface can be employed to enhance the diffraction efficiency of surface grating structure composed of biomolecules. Based on a Kretschmann configuration, we realized a diffraction biosensor to monitor the dynamic interaction of biological molecules in a label-free way. It was demonstrated by the binding of an anti-biotin antibody to the biotin-functionalized region of a periodically patterned surface, which generated significant optical contrast to diffract the surface plasmon field. With the aid of the synchronic surface plasmon resonance signal, a quadratic dependence of diffraction signal on the amount of bound antibody was found, which coincides with the theoretical expectation. Time-dependent measurements were conducted to estimate the density of biotin thiols on the functional region.

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Antibodies, MonoclonalBiosensing TechniquesBiotinKineticsMicroscopy, Electron, TransmissionSurface Plasmon ResonanceSurface PropertiesTime FactorsX-Ray DiffractionJournal ArticleResearch Support, Non-U.S. Gov't

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Fang Yu, Shengjun Tian, Danfeng Yao, Wolfgang Knoll. 2004-07-01. Surface plasmon enhanced diffraction for label-free biosensing.. https://doi.org/10.1021/ac049964p

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