A Holder for Simultaneous Fluid Processing or Carbon Coating of Electron Microscope Grids in Lots of 10 or More

Abstract

A piece of polyethylene tubing about 14 cm long, ID 3 mm and with a 1.5 mm wall is shaped to hold grids in a linear series as follows. A series of pairs of transverse cuts I mm apart are made across and about $3/4 through the tubing at intervals of 1 cm. After making diagonal cuts on either side of each pair of cuts, wedge-shaped pieces of tubing are removed to leave free-standing 1 mm widths of the tubing wall. Each arch of wall is then bisected by a cut in the longitudinal direction of the tubing, thus providing the jaws of a clamp for a grid. By spreading the jaws with forceps, the grid can be inserted. On removal of the forceps, the grid is held firmly and when the holder is filled, the grids face in a direction perpendicular to its long dimension. By inserting a piece of glass tubing into the lumen of the holder, it is held straight and can be placed in a test tube for fluid processing. Stains or other fluids can be introduced through the glass tube, thus allowing fluid changes without exposure to air. Carbon coating can be achieved without removing the grids, since they all face the same way. For convenience in loading and unloading, the holder can be temporarily attached to a base with double-coated adhesive tape.