Use of a Glass Edge in Thin Sectioning for Electron Microscopy.

Abstract

Inexpensive glass cutting edges that require no sharpening have been found to yield sections of biological material that are thin enough for electron microscopy and freer of knife marks and scratches than are sections cut with a steel knife. The knives are made by breaking a strip 1.5 in. wide and about 12 in. long from a sheet of plate glass approx. 0.375 in. thick. A series of parallel scorings are then made on each strip at 45[degree] to the long axis. The parallelograms thus outlined are broken off, producing a set of glass blocks, each of which has two cutting edges 0.375 in. long, formed by facets meeting at 45[degree]. A simply constructed knife holder to accommodate the glass knives is described. Electron micrographs of representative sections of nerve tissue illustrate the results obtainable. The useful life of the glass edge compares very favorably with that of a freshly sharpened steel edge, and dulled edges are simply discarded. The glass knives can be produced at low cost from stock plate glass by any competent glass cutter using standard equipment. Tedious and uncertain knife sharpening procedures are eliminated.