Strategies for sample preparation

Mixtures for sealing

Nail polish / nail hardener: To seal and to fix cover slips (separated from the slide by a thin layer of plastic cut off a freezer bag, or by other spacers), I use nail hardener, but sometimes I run into problems with its bad long-time contact with the slide surface. (Slides may be "contaminated" with embedding medium, or some mounting medium may penetrate slowly into or below the "hardened" glue).

VALAP: This is a 1:1:1 mixture of vaseline, lanolin and paraffin. It is prepared by mixing the components in a glass beaker or bottle on a heating plate. The mixture is applied by a small brush with a thin tip and hardens immediately. It can be reheated / reused many times. The mixture is preferred in cases where solvents of nail polish etc. may interfere (e.g. for life cell preparations).