Protocol for ProtoSlo

[NikonUser]

Mitch asked how I use ProtoSlo.
First I must thank Charles Krebs for alerting me to this product.
It is Hydroxyethyl cellulose and is commonly used to slow down protozoa on a microscope slide. Works well for many (all?) small aquatics.
Also I thank Charles for his Petroleum Jelly technique.

I first isolate a specimen in a cavity slide by a combination of pipetting it into a clean cavity and/or pipetting out all the 'junk' in the water. Then, under a dissecting scope, with the specimen in a few drops of water I add a small drop of ProtoSlo and stir the mixture with the tip of pipette, sometimes even sucking up the mixture and squirting it out (gently). If the specimen is still very active, I add more drops until the specimen just about stops moving.

I use a very thick grease to raise the coverglass off the slide (Charles' method). To do this I heat the grease on a warm surface until it liquifies and then pick up a drop with the head of a pin and deposit on a preset position on a large microscope slide; repeat with 3 other drops. The liquid oil turns to a thick grease almost instantaneously.

Place specimen in its drop of water/ProtoSlo in the center of the slide and drop on a coverslip. Again under the scope I gently press on the coverslip to move it closer to the slide, leaving just enough room so as not to squash the specimen (again, Charles' method).

Crude template for positioning of oil/grease
4 grease spots on slide.


NU10096

[DaveW]

Not into microscopy, but there was a programme many years ago on British TV where they used cellulose wallpaper paste for the same purpose to slow them down and it's easily obtainable at DIY stores.

"unless we slow it down. We will use methyl cellulose (wallpaper paste) to do this."

http://www.modernmicroscopy.com/main.as ... print=true

DaveW

[Mitch640]

Nice detailed explanation. I was under the impression it took a lot less Protoslo than what you describe. This makes more sense.

I have not tried the grease spot technique yet. I use clear nail polish which works very well. After it dries, it leaves a small gap that allows animals as big as a Gammarus Shrimp to lay on it's side without killing it, but not move. Not sure how you would ever measure that gap.

[rjlittlefield]

Not sure how you would ever measure that gap.

Focus on some debris on the bottom side of the cover slip, then refocus on some debris sitting on the slide itself. Subtract the micron indications on the fine focus knob.

I use a very thick grease to raise the coverglass off the slide

What kind of grease?

BTW, this is a great writeup -- many thanks!

--Rik

[NikonUser]

Thanks guys.

Mitch: The beauty of grease over nail polish is that you can lean on the grease and vary the depth of water; with nail polish you are limited to to just one depth.
I'm almost as anxious as you to see the details of your new scope.

Rik: I use pure Lanolin from Fisher Scientific. It's an old jar I have had for years and in the cold state it's almost solid but still flexible (squashable) when used as a tiny droplet. I've tried various wheel bearing greases and Petroleum Jelly (Vaseline) but found them too soft.

[Mitch640]

I'm almost as anxious as you to see the details of your new scope.

It's beginning to get to me now. Delivery should be today or tomorrow by 5pm at the latest. I woke up 3 times last night worried that the scope had fallen off the back of the truck coming across the Dakotas or that it had come loose in the truck and gotten crushed by something else. I use to drive cross country semi's and I know what can happen.