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Optical imaging of single-protein size, charge, mobility, and binding.

ABSTRACT: Detection and identification of proteins are typically achieved by analyzing protein size, charge, mobility and binding to antibodies, which are critical for biomedical research and disease diagnosis and treatment. Despite the importance, measuring these quantities with one technology and at the single-molecule level has not been possible. Here we tether a protein to a surface with a flexible polymer, drive it into oscillation with an electric field, and image the oscillation with a near field optical imaging method, from which we determine the size, charge, and mobility of the protein. We also measure antibody binding and conformation changes in the protein. The work demonstrates a capability for comprehensive protein analysis and precision protein biomarker detection at the single molecule level.

SUBMITTER: Ma G

PROVIDER: S-EPMC7505846 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Optical imaging of single-protein size, charge, mobility, and binding.

Ma Guangzhong G Wan Zijian Z Yang Yunze Y Zhang Pengfei P Wang Shaopeng S Tao Nongjian N

Nature communications 20200921 1

Detection and identification of proteins are typically achieved by analyzing protein size, charge, mobility and binding to antibodies, which are critical for biomedical research and disease diagnosis and treatment. Despite the importance, measuring these quantities with one technology and at the single-molecule level has not been possible. Here we tether a protein to a surface with a flexible polymer, drive it into oscillation with an electric field, and image the oscillation with a near field o ...[more]

PMID: 32958747

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