Details: The virus was mixed in NTE buffer (10 mM Tris, 120 mM NaCl, and 1 mM EDTA at pH 8) with 50 mM MES, 120 mM NaCl at pH 5.6 to yield a final pH of 6 pH: 6
A small vial of ethane is placed inside a larger liquid nitrogen reservoir. The grid holding a few microliters of the sample is held in place at the bottom of a plunger by the means of fine tweezers. Once the ethane in the vial is completely frozen, it needs to be slightly melted. When the liquid ethane is ready, a piece of filter paper is then pressed against the sample to blot of excess buffer, sufficient to leave a thin layer on the grid. After a predetermined time, the filter paper is removed, and the plunger is allowed to drop into the liquid ethane. Once the grid enters the liquid ethane, the sample is rapidly frozen, and the grid is transferred under liquid nitrogen to a storage box immersed liquid nitrogen for later use in the microscope.