Abstract
A method is described for preparing ‘low-noise’ graphite support films for high resolution electron microscopy. The films were prepared by ultrasonic exfoliation and centrifugation of high purity powders of natural graphite and subsequent application of the supernatant on to reticulate carbon supports (micro grids). Relative dark field intensity measurements indicated that the graphite cyrstals had thicknesses between 2 and 5nm; useful areas up to 20μm 2 were often observed. As opposed to evaporated amorphous carbon films, the graphite films had a characteristics non-speckled appearance over a wide defocus range. Comparison tests between graphite and amorphous carbon support films 1.3 and 25nm thick, revealed reduction in the noise spectra amplitudes of 1 4 and 1 9 respectively. Negatively stained ferritin molecules supported on graphite crystals yielded a significant improvement in the signal-to-noise ratio.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
