Tuning Specific Biomolecular Interactions Using Electro-Switchable Oligopeptide Surfaces

Authors

  • Chun L. Yeung,

    1. School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343
    2. School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK)
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  • Parvez Iqbal,

    1. School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343
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  • Marzena Allan,

    1. School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343
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  • Minhaj Lashkor,

    1. School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343
    2. School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK)
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  • Jon A. Preece,

    1. School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK)
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  • Paula M. Mendes

    Corresponding author
    1. School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343
    • School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT (UK), Tel: Int. code +(121) 414-5343.
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Abstract

The ability to regulate biomolecular interactions on surfaces driven by an external stimuli is of great theoretical interest and practical impact in the biomedical and biotechnology fields. Herein, a new class of responsive surfaces that rely on electro-switchable peptides to control biomolecular interactions on gold surfaces is presented. This system is based upon the conformational switching of positively charged oligolysine peptides that are tethered to a gold surface, such that bioactive molecular moieties (biotin) incorporated on the oligolysines can be reversibly exposed (bio-active state) or concealed (bio-inactive state) on demand, as a function of surface potential. The dynamics of switching the biological properties is studied by observing the binding events between biotin and fluorescently labeled NeutrAvidin. Fluorescence microscope images and surface plasmon resonance spectral data clearly reveal opposite binding behaviors when +0.3 V or −0.4 V vs. SCE are applied to the surface. High fluorescence intensities are observed for an applied positive potential, while minimal fluorescence is detected for an applied negative potential. Surface plasmon resonance spectroscopy (SPR) results provided further evidence that NeutrAvidin binding to the surface is controlled by the applied potential. A large SPR response is observed when a positive potential is applied on the surface, while a negative applied potential induces over 90% reduction in NeutrAvidin binding.

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