Is it possible to observe biological macromolecules by electrostatic force microscopy?

Biological macromolecules such as proteins are charged species in solution. The exact charge depends upon the pH, temperature and ionic strength of the medium in general. This suggests the possibility of employing electrostatic force microscopy as a useful tool for the observation of these macromolecules. Our calculations show that electrostatic forces could be used for this purpose, thus helping to remove ambiguities in the location and identification of proteins. The long-range nature of electrostatic forces could make them useful to locate these macromolecules on the appropriate substrate while, at the same time, overcoming important disturbing effects such as lateral displacement of the macromolecules or destructive contact with the sample.