Tip-Sample Interactions in Atomic Force Microscopy: I. Modulating Adhesion Between Silicon Nitride and Glass
Abstract
An adhesive interaction between a silicon nitride AFM tip and glass substrate in water is described. This adhesion is in the range 5-40nN, of which a large component is likely to be due to hydrogen bonding between the silanol groups on both surfaces. The interaction can be modulated by a variety of buffers commonly used in biochemical and biological research, including sodium phosphate, tris(hydroxymethyl)aminomethane, glycine, and N-2- hydroxyethylpiperazine N'-2-ethanesulfonic acid. Using these buffers it appears that there are effects of ion concentration, ion type, and pH on the measured adhesion. Of the conditions examined, phosphate was most effective at reducing adhesion and could be used at concentrations as low as 10 mM at neutral pH. The results demonstrate that the chemical interactions between tip and sample can be modulated, and provide a basis for designing conditions for imaging and manipulating biological molecules and structures.... Biological macromolecules, Cellular organelles, Whole cells, Modulation of interactions, Silicon nitrate tip, Substrate, Hydrogen bonds
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1991
- Accession Number
- ADA268959
Entities
People
- Jan H. Hoh
- Jean-paul Revel
- Paul K. Hansma
Organizations
- University of California, Santa Barbara