atomic force microscopy

Syllable breakdown

Dictionary meaning

a type of scanning probe microscopy in which a sharp tip mounted at the end of a cantilever is scanned across a sample surface while a feedback mechanism maintains a constant interaction force — or constant cantilever deflection — between tip and sample, generating a three-dimensional topographic map of the surface with sub-nanometre resolution; invented by Gerd Binnig, Calvin Quate, and Christoph Gerber in 1986, AFM does not require the electrically conducting samples needed for scanning tunnelling microscopy and can image biological samples under physiological conditions in liquid; beyond topographic imaging, AFM is used to measure mechanical properties — stiffness, adhesion, friction — of surfaces at the nanoscale, to manipulate individual atoms and molecules, and to characterise electrical, magnetic, and chemical properties with nanometre resolution; AFM is indispensable in nanotechnology, materials science, and cell biology

Examples

• Atomic force microscopy revealed that the cell membrane of cancerous cells is significantly softer than that of healthy cells.
• AFM was used to directly visualise individual DNA molecules and measure their mechanical elasticity.

Synonyms: AFM, scanning force microscopy