Imaging of biological macromolecules on mica in humid air by scanning electrochemical microscopy.
Imaging of DNA, keyhole limpet hemocyanin, mouse monoclonal IgG, and glucose oxidase on a mica substrate has been accomplished by scanning electrochemical microscopy with a tungsten tip. The technique requires the use of a high relative humidity to form a thin film of water on the mica surface that allows electrochemical reactions to take place at the tip and produce a faradaic current (approximately 1 pA) that can be used to control tip position. The effect of relative humidity and surface pretreatment with buffer solutions on the ionic conductivity of a mica surface was investigated to find appropriate conditions for imaging. Resolution of the order of 1 nm was obtained.
Fan
F R
FR
Department of Chemistry, University of Texas, Austin, TX 78712, USA.
Bard
A J
AJ
D000538:Aluminum Silicates; D000818:Animals; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D005949:Glucose Oxidase / Q000737:chemistry; D006433:Hemocyanins / Q000737:chemistry; D006813:Humidity; D007074:Immunoglobulin G / Q000737:chemistry; D051379:Mice; D008853:Microscopy; D011506:Proteins / Q000737:chemistry*
D000538:Aluminum Silicates; D007074:Immunoglobulin G; D011506:Proteins; D004247:DNA; D006433:Hemocyanins; D005949:Glucose Oxidase; C011934:mica