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Atomic Force Microscopy Of Dna On Mica And Chemically Modified Mica, T. Thundat, D. P. Allison, R. J. Warmack, G. M. Brown, K. B. Jacobson, J. J. Schrick, T. L. Ferrell
Atomic Force Microscopy Of Dna On Mica And Chemically Modified Mica, T. Thundat, D. P. Allison, R. J. Warmack, G. M. Brown, K. B. Jacobson, J. J. Schrick, T. L. Ferrell
Scanning Microscopy
Atomic force microscopy (AFM) was used to image circular DNA adsorbed on freshly cleaved mica and mica chemically modified with Mg(II), Co(II), La(III), and Zr(IV). Images obtained on unmodified mica show coiling of DNA due to forces involved during the drying process. The coiling or super twisting appeared to be right handed and the extent of super twisting could be controlled by the drying conditions. Images of DNA observed on chemically modified surfaces show isolated open circular DNA that is free from super twisting, presumably due to strong binding of DNA on chemically modified surfaces.
Calibration Of Atomic Force Microscope Tips Using Biomolecules, T. Thundat, X.-Y. Zheng, S. L. Sharp, D. P. Allison, R. J. Warmack, D. C. Joy, T. L. Ferrell
Calibration Of Atomic Force Microscope Tips Using Biomolecules, T. Thundat, X.-Y. Zheng, S. L. Sharp, D. P. Allison, R. J. Warmack, D. C. Joy, T. L. Ferrell
Scanning Microscopy
Atomic force microscope (AFM) images of surfaces and samples mounted on substrates are subject to artifacts such as broadening of structures and ghost images of tips due to the finite size and shape of the contacting probe. Therefore, knowledge of the radius of the AFM probe tip is essential for the interpretation of images. We have deduced the shape of the AFM tip by imaging cylindrical biological molecules of various diameters such as deoxyribonucleic acid (DNA), tobacco mosaic virus (TMV), tobacco etch virus (TEV) and bacteriophage M-13 (M-13). Using a paraboloidal tip model and numerically solving equations of contact, the …
A Review Of Graphite And Gold Surface Studies For Use As Substrates In Biological Scanning Tunneling Microscopy Studies, Carol R. Clemmer, Thomas P. Beebe Jr.
A Review Of Graphite And Gold Surface Studies For Use As Substrates In Biological Scanning Tunneling Microscopy Studies, Carol R. Clemmer, Thomas P. Beebe Jr.
Scanning Microscopy
The current status of biological Scanning Tunneling Microscopy (STM) investigations and the importance of using a well-characterized substrate are discussed. The findings of over two years of experiments and over 1,000 images obtained on gold substrates prepared by a variety of different methods are statistically summarized and compared to a very flat reference substrate, highly oriented pyrolytic graphite (HOPG). In an effort to begin to corroborate STM results with those obtained from other more established techniques, the results of Auger Electron Spectroscopy (AES) and Electron Spectroscopy for Chemical Analysis (ESCA) of biomolecular STM samples are presented.