Making long-lasting slides

[DonSchaeffer]

I have some great specimens of algae with diatoms. Is it possible to preserve these? How? How do you use nail polish in making permanent slides?

[daruosha]

There are many ways of making permanent slides, however I'd like to suggest a series of article written by Walter Dioni:

Part 1: Introduction - liquid media.
http://www.microscopy-uk.org.uk/mag/art ... ount2.html

Part 2: Soldifying media.
http://www.microscopy-uk.org.uk/mag/art ... ount3.html

Part 3 - Mixed mounting media - Part A; fructoglycerol and modified Brun's medium as mountants
http://www.microscopy-uk.org.uk/mag/art ... art3a.html

Part 3b. PVA-lactic acid and PVA-glycerol
http://www.microscopy-uk.org.uk/mag/art ... art3b.html

Part 3c - Gum arabic media
http://www.microscopy-uk.org.uk/mag/art ... art3c.html

Part 4 -Glycerine jellies.
http://www.microscopy-uk.org.uk/mag/art ... part4.html

[Hobbyst46]

I have some great specimens of algae with diatoms. Is it possible to preserve these? How? How do you use nail polish in making permanent slides?

I doubt that nail polish is appropriate as mountant for slides of alga and diatoms. Nail polish does not mix well with water. Hence, the alga specimen must be dried prior to mounting in th nail polish. What is more, nail contains powerful solvent (similar to acetone) that will cause shrinkage and deformation of the alga, and loss of pigment.
For alga, I tried (separately) glycerine and fructose syrup. Glycerine does not solidify, but otherwise is easy to mount in it, since it is totally miscible with water. However, glycerine causes loss of color of the alga within days. On the other hand, if the coverslip is sealed with a ring (of nail polish...) the slide will keep for a very long time.
Fructose syrup is sometimes better than glycerine, in that it preserves the green pigment; yet, because of the osmotic shock, it is liable to deform the alga cells - depends on the alga.
Fructose syrup can be applied directly to the near-dry alga. Does not solidify. After sealing, it keeps for years.
One problem with all viscous mountants is air bubbles. Try not to invert or shake the bottle for a couple of days before mounting. Pick out a small drop of mountant with a toothpick or the end of a simple straightened paper clip, not with a dropper or pipette.

In general, I believe there are better mountants, maybe glycerine jelly (see many beautifully informative posts by mrsonchus), and others described by W. Dioni.
P.S. just remembered that I mounted in paper-glue - polyvinyl alcohol, with or without anti-bacterial agents; again, the advantage is total miscibility with water, so no need to completely dry the alga. But the results were disappointing - often, crystallization of some sort.
There are commercial water-based mountants, do not know which of them fits alga.

[DonSchaeffer]

How about muscelage--you know the old fashioned clear paper glue?