Atomic force microscope imaging contrast based on molecular recognition.

M Ludwig; W Dettmann; H E Gaub

doi:10.1016/s0006-3495(97)78685-5

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PubMed · 8994631

Atomic force microscope imaging contrast based on molecular recognition.

M Ludwig·W Dettmann·H E Gaub

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Abstract

The contrast in atomic force microscope images arises from forces between the tip and the sample. It was shown recently that specific molecular interaction forces may be measured with the atomic force microscope; consequently, we use such forces to map the distribution of binding partners on samples. Here we demonstrate this concept by imaging a streptavidin pattern with a biotinylated tip in a novel imaging mode called affinity imaging. In this mode topography, adhesion, and sample elasticity are extracted online from local force scans. We show that this technique allows the separation of these values and that the measured binding pattern is based on specific molecular interactions.

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Adhesiveness Avidin Bacterial Proteins Biotin Carbohydrate Sequence Dextrans Gold Hydrogen Bonding Microscopy, Atomic Force Molecular Sequence Data Protein Conformation Streptavidin Journal Article Research Support, Non-U.S. Gov't

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M Ludwig, W Dettmann, H E Gaub. 1997. Atomic force microscope imaging contrast based on molecular recognition.. https://doi.org/10.1016/s0006-3495(97)78685-5

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