Distilled glutaraldehyde: its use in an improved fixation regime for cell suspensions

A method is described for the sequential fixation of cell suspensions, suitable for use at room or culture temperatures. Though an adequate method for fixing cell suspensions does exist in the literature (Hirsch & Fedorko, 1968), it involves the use of a mixed glutaraldehyde-osmium tetroxide fixative. Since these two components inter-react, this method has many drawbacks. Previously described weaknesses of a sequential fixation regime (Hirsch & Fedorko, 1968; Jones, Yeh & Hirsch, 1972) with glutaraldehyde and osmium tetroxide have been overcome by the use of vacuum distilled glutaraldehyde as the primary fixative. The results, using a mixed glutaraldehyde-osmium tetroxide fixative and using the two components sequentially on a variety of cell types, are compared. The advantages of a sequential fixation made possible by the use of vacuum distilled glutaraldehyde rather than commercial glutaraldehyde are discussed.