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A Bifunctional Spin Label for Ligand Recognition on Surfaces.

ABSTRACT: In?situ monitoring of biomolecular recognition, especially at surfaces, still presents a significant technical challenge. Electron paramagnetic resonance (EPR) of biomolecules spin-labeled with nitroxides can offer uniquely sensitive and selective insights into these processes, but new spin-labeling strategies are needed. The synthesis and study of a bromoacrylaldehyde spin label (BASL), which features two attachment points with orthogonal reactivity is reported. The first examples of mannose and biotin ligands coupled to aqueous carboxy-functionalized gold nanoparticles through a spin label are presented. EPR spectra were obtained for the spin-labeled ligands both free in solution and attached to nanoparticles. The labels were recognized by the mannose-binding lectin, Con?A, and the biotin-binding protein avidin-peroxidase. Binding gave quantifiable changes in the EPR spectra from which binding profiles could be obtained that reflect the strength of binding in each case.

SUBMITTER: Hollas MA

PROVIDER: S-EPMC5577508 | biostudies-other | 2017 Aug

REPOSITORIES: biostudies-other

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A Bifunctional Spin Label for Ligand Recognition on Surfaces.

Hollas Michael A MA Webb Simon J SJ Flitsch Sabine L SL Fielding Alistair J AJ

Angewandte Chemie (International ed. in English) 20170706 32

In situ monitoring of biomolecular recognition, especially at surfaces, still presents a significant technical challenge. Electron paramagnetic resonance (EPR) of biomolecules spin-labeled with nitroxides can offer uniquely sensitive and selective insights into these processes, but new spin-labeling strategies are needed. The synthesis and study of a bromoacrylaldehyde spin label (BASL), which features two attachment points with orthogonal reactivity is reported. The first examples of mannose an ...[more]

PMID: 28570782

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