January 23, 2009: SiMPore Inc., a company commercializing nanotechnology invented at the University of Rochester, has developed an ultrathin microscope slide that significantly improves high-resolution imaging of nanoscale materials such as proteins, viruses and carbon nanotubes, the company announced in a news release.
This is the first commercial application of a unique nanomembrane initially reported in Nature in 2007, the release said.
These new slides, more commonly called windows for electron microscopy, are made of a proprietary silicon membrane so thin that it is invisible edge-on. The extreme thinness of the windows — less than 50 atoms thick — reduces background interference and improves contrast in images generated with transmission electron microscopes ( TEM ), making individual biological molecules, like proteins or viruses, easier to analyze.
Unlike conventional TEM windows, SiMPore’s also have a pure silicon composition meaning that they can be subjected to intense plasma cleaning to remove contaminants, which further improves image quality.
SiMPore’s slides, or windows, are made of a proprietary silicon membrane so thin that it is invisible edge-on. (Image courtesy of SiMPore Inc.)
TEM windows are effectively used as slides to support samples that will be imaged and analyzed with an electron microscope. Imaging is done by focusing a beam of electrons onto a sample, whereby some electrons transmit through the sample and others are scattered out of the beam. The electrons that emerge from the sample carry structural information about the sample that can be magnified by the lens system of the microscope and used to produce a detailed image of atomic scale features.
While the best light microscopes have magnifications of up to 2,000×, some electron microscopes can magnify objects at millions of times their actual size.
Christopher Striemer, now vice president of membrane development at SiMPore, discovered the membrane technology that underlies the new TEM windows while working with nanocrystalline silicon films for computer chip memory applications. By transforming those films into membranes only 15 nanometers thick, he could more precisely image the intricate crystalline structures of his samples using an electron microscope.