Permanent Mounting Trials

[Roldorf]

My next project is to look at some of the DIY permanent mounting solutions I have found on the internet.

The first is with Nail Polish which I bought a bottle of a couple of weeks ago.




Sorry about the advertising but if it works you will want to know what I bought.
Most of the information I have found on the internet say not to use the base and top coat combined, however I bought this before I read those posts but what the heck, it is a 'trial' so I will try it anyway.

I wanted to try this out on a subject that they say is very difficult to make DIY permanent mounts of and also something that was plentiful, within easy reach and wont be missed, so that when it failed I could easily try again.
Hence Nasturtium's, they are growing all over the place in our back garden.

First step was to make a cross section of the leaf stem, dry mount it and make an image for control.

Here it is:-



Step 2 will be to repeat my section but I will mount it direct with nail varnish. Hopefully today so all my samples are roughly the same age.

Step 3. Soak it in alcohol for an hour while I have lunch then section it and mount it in the polish.

Then I will wait and see.

[mrsonchus]

Hi Alan, great adventure! Is the image definitely of a cross-section? The vasculature looks to be longitudinally-oriented as if this were a longitudinal section....
Hmm, is the section taken 'right up against' the leaf-blade?
That may explain the orientation and the more round and laterally-oriented LH corner of the image, as if the vasculature radiates from a center as the leaf structure shows?

Looking forward to following your progress my friend.

[Roldorf]

Hi John. I noticed that, maybe the section got tipped and then I squashed it with the coverglass. Having said that it was a very thin section even though I did it with a regular razor blade so I don't see how it could 'tip'. Anyway I will cut them and mount them the same way.

Part 2 has been prepared but I haven't looked at it yet. Part 3 is in the alcohol (it's called Brand alcohol here in Gemany when I used to go camping with my parents in the 50's it was meths and a very pretty purple pink colour to stop people drinking it (didn't work though for some).

Should have a result now on part 2 so will go and take an image.

[mrsonchus]

Sounds good - keep us updated!

[Roldorf]

Here we go. Mounted in nail polish no prior treatment.




Seems to have lost a bit of Chlorophyll. !! Will see how it develops over the next few days.
Now going to get the alcohol sample and make a section in the same way.

[Roldorf]

Last one for the nail polish test.
Soaked in 90% alcohol for around one hour.
Mounted with nail polish:

Time will tell.

[Roldorf]

Next test will be with Glass Bond (UHU Glass), forget where on the internet I saw that being used. A much more expensive solution than Euparal or Nail Varnish, but much easier to get hold of (local DIY), but more difficult to get off your fingers. No postage, no waiting, no using card over the internet.
So next trip to Hornbach!!!

[Hobbyst46]

Next test will be with Glass Bond (UHU Glass), forget where on the internet I saw that being used. A much more expensive solution than Euparal or Nail Varnish, but much easier to get hold of (local DIY), but more difficult to get off your fingers. No postage, no waiting, no using card over the internet.
So next trip to Hornbach!!!

There are two potential issues witg nail polish
1. Air bubbles.
2. It leaches the chlorophyll out of plants. To preserve the chlorophyll for months, neither glycerol nor nail polish are good. Strong fructose solution, or Karo, are better in this respect. Also polyvinyl alcohol glue is better.

[MicroBob]

Hi Alan,
is it possible that your sections are quite thick? When you are cutting freehand it is is the easiest to start thin and wedge the cut out to zero. This way you have at least an area where the thickness is quite good, like 50µ or so. When you leave a little water in the sections the mountant will have to be compatible with it. In Canadabalsam the water would stay encapsulated and the section would rot and the image would be cloudy. Maybe a water-soluble glue would work, perhaps school paper glue or wall paper- "Kleister" or classic paper glue on gum arabicum base (still available). For a permanent mount it shouldn't tend to crystalize.

I posted a link to an extensive research paper where the permanence of old slides was the topic. Perhaps you could find a hint for alternative mountants there.

Bob

[Roldorf]

Hobbyst46

Yes I had seen some posts that said air bubbles could be a problem, but I think I got away fairly light on these two tries, only one small air bubble, of course there could be more forming. I will have a good look tomorrow again to see what's happening.
I just read about Fructose today will have to explore that some more.

[Roldorf]

Hi MicroBob

Yes it is more than possible they are thick. I should probably have used a new razorblade. This one has been in service for a long time now. (last year's mushroom season). As you can guess I have to watch the pennies/cents, pensions don't grow on tree's, so I shall retire the razorblade in favor of a new one.
'Barmy Boris & Co' are really screwing with the value of my pension (-25% drop in Euros in one year).

I don't expect to come up with a wonderful DIY mounting solution, it's the fun gained in the experiment that is the aim. That's how come we have all of these wonderful solutions today, people 'playing' around.

[MicroBob]

Hi Alan,
real microtom blades are honed just before use for critical applications because the edge degrades a little bit from the point of time it has been sharpened.
So it might be an idea to just hone your razor blade from time to time. A cheap an easy solution is polishing wax on a strip of hard smooth leather (e.g. a belt) of a strip of planed fir wood.
I myself like to develop simplified mounting methods a lot. I came up with a a very simple method to make stunning radiolaria slides this way. A retired zoology professor who held the lecture at the meeting would have been happy to have this methods for the work with his students in his active times, so there are still things to optimize.
A wide area is the adjusting of methods to fit in the amateur lab of today. I sometimes have the picture in the head of an old time microscopist doing his preparations and plants, animals and fellow human beings falling apart in the chemical fog he creates.
There are lots of methods with chemicals that even an experienced chemist doesn't really like to have around and todays laws have a big impact too.
A typical topic is diatoms here: Cleaning in concentrated acids and H2O2, mounting in "yellow medium".

Just today I had a look at the first of a set of diatom slides Doron has made himself and sent me: Cleaned with safe methods, mounted with a UV glue and perfectly usable. So it really is possible to get nice slides with nice methods. These methods also make it more feasible for people around the globe and for future generations to use microscopy as a means of research and recreation!
A couple of days ago I was told that it isn't allowed any more to use Phenolphtalein (ph indicator) in german schools!

Bob

[Hobbyst46]

My favor for fructose rests on the recommendations of Walter Dioni. I find that it preserves the green color of plant parts (e.g. Moss, algae) for about a year and even longer, after sealing with nail polish. So does PVA. Glycerin does not have this feature.

[Roldorf]

Microbob & Hobbyst46

Thanks for the recommendations, more methods to try in my trials. Would I be correct in assuming Fructose can be bought in Edeka as einfach sugar? Then simply mixed with water? The UHU glass glue is hardened by UV light (daylight).

[Hobbyst46]

...Would I be correct in assuming Fructose can be bought in Edeka as einfach sugar? Then simply mixed with water?

Fructose, or fruit sugar, is a white granular powder. I bought it at a natural products store (sort of "organic market"). The smallest quantity was 1Kg, cost 2$ and will last until Man lives on the Mars. To make a very concentrated solution, nearly a syrup, say ~80%, add the sugar gradually to distilled water in a Pyrex glass or beaker and mix. It dissolves much faster if the beaker is placed within a pot of boiing water. The mixture itself need not boil. Upon cooling, it will not crystallize but become honey-like viscous. Store in a stoppered jar at RT.
Note, air bubbles are a problem with this medium too.

...The UHU glass glue is hardened by UV light (daylight)

Actually, for diatoms, I used a special glass glue called NOA61. It has an nD of 1.56-1.6 and is cured with UV or strong direct sunlight. It is not compatible with wet plant tissues.

[Roldorf]

Searching for Fructose today in the supermarket, couldn't find any so bought some 'gelier sugar 2:1' as an alternative (who knows it may work).
I have just made up a concentrated solution I hope and stored it in a small dropper bottle (it's still warm) so will wait a while then have a look to see if it turns syrupy.
Later today I will have another look at the slides I made yesterday to see how they are doing.
We found our first mushroom of the season today, it's sitting on a slide to make a spore print. Will have a look later, images to come.

Hobbyst46 Edit: Is this NOH61, Norland 61 that you can get from Edmund Scientific Co?

[MicroBob]

Hi Alan,
"Fruchtzucker" is what you need. You can get it at Edeka or Rewe, but probably not at Aldi.
The "Gelierzucker" is a mixture of Pectin with probably ordinary sugar. They would write it on the package and double the price if it would include fructose.
Pectin alone is probably what you get when you buy "Gelierfix", in small bags, no sugar included. It might be an interesting component of a mountant too.

Bob

[Dave S]

Alan, Fructose can usually be found in Health Food shops.

Such as shops like this in the UK: https://www.hollandandbarrett.com/shop/ ... lsrc=aw.ds

I'm sure there must be an equivalent in Germany.

[Roldorf]

HI Bob & Dave. It was Rewe where I tried to get it but didn't see any. I will try the Jelly sugar first. There is a small Edeka Just across the street so I will have a look tomorrow. Maybe I will be in luck.

Looked at the last slides I did with the nail varnish and the only changes I could see were some large voids in the varnish. I think I should have put some small weights on the cover glass before I left them to dry.
Next time.

No change in the chlorophyll still looks the same.

[Hobbyst46]

Searching for Fructose today in the supermarket, couldn't find any so bought some 'gelier sugar 2:1' as an alternative (who knows it may work).
I have just made up a concentrated solution I hope and stored it in a small dropper bottle (it's still warm) so will wait a while then have a look to see if it turns syrupy.
Later today I will have another look at the slides I made yesterday to see how they are doing.
We found our first mushroom of the season today, it's sitting on a slide to make a spore print. Will have a look later, images to come.

Hobbyst46 Edit: Is this NOH61, Norland 61 that you can get from Edmund Scientific Co?

1. Fructose: Fructose and similar sugars (glucose - grape sugar, sucrose - ordinary cane or beet sugar) readily dissolve in water to give very concentrated, syrupy solutions. Probably, they could all be used for mounting. Walter Dioni suggested fructose, apparently because fructose is said to be less prone to crystallization. I adopted his suggestion and never searched for detailed data about the sugar syrups.
2. I used NOA61 = Norland 61. I keep it in a fridge, to increase its shelf life.

[Hobbyst46]

Pectin alone is probably what you get when you buy "Gelierfix", in small bags, no sugar included. It might be an interesting component of a mountant too.

Possibly, on the long run, it will be attacked by microbes or mold. Gelatine-based mountants are better protect with an anti bacterial agent.

[mrsonchus]

Pectin alone is probably what you get when you buy "Gelierfix", in small bags, no sugar included. It might be an interesting component of a mountant too.

Possibly, on the long run, it will be attacked by microbes or mold. Gelatine-based mountants are better protect with an anti bacterial agent.

True, when I made some of my own glycerin-jelly mountant as-per Walter Dioni's experiments, the formula included a measure of disinfectant - I used 'Lysterine' mouthwash but I'm sure anything similar would do.

A link to making glycerin jelly mountant with Lysterine...

[MicroBob]

Pectin alone is probably what you get when you buy "Gelierfix", in small bags, no sugar included. It might be an interesting component of a mountant too.

Possibly, on the long run, it will be attacked by microbes or mold. Gelatine-based mountants are better protect with an anti bacterial agent.

True, when I made some of my own glycerin-jelly mountant as-per Walter Dioni's experiments, the formula included a measure of disinfectant - I used 'Lysterine' mouthwash but I'm sure anything similar would do.

A link to making glycerin jelly mountant with Lysterine...

Here in Germany you can buy Gelierfix 3:1 for jam with 3 parts fruit to 1 part sugar. Since there is too little sugar to do the conserving they add a conservative. Such jam can be stored for a couple of years, even witt less sugar content.

[Roldorf]

Managed to get some Einmacht (fructose) sugar today from the small Edeka across the street. Spent the last hour and a half making a concentrated solution. Tomorrow I will try the two mixtures out, sealing the resulting slide with nail varnish. Not forgetting to put some small weights on while they dry.

[MicroBob]

Not forgetting to put some small weights on while they dry.

Hi Alan, screw nuts are useful for this application, e.g. an M8 nut.
In my experience this doesn't help a lot when the cut is too thick because the cover slip tilts when the solvent evaporates out of the mountant.
But depending on you decterity it is no real problem to acheive nice sections free hand as long as the material is nice to cut. Some plant stems offer quite a resistance to the cutting force, but also consist of mushy cells the tear when being cut. This here was such an example: viewtopic.php?f=6&t=7013&hilit=sansevieria
It also becomes more difficult with increasing diameter of the stem.
Easy to cut subjects are daisy stems.

One section always is the result of two cuts. The more uniform the cutting, the better the results.

Bob

[Roldorf]

The search goes on the first one is with Fructose (maybe I made it a bit thick?).
Not so good lots of bubbles and colour a bit bleached out:-



The second is with Gelierzucker 2:1 looks a lot better not many bubbles in this one and not so bleached.
Both slides were weighted with an M8 nut and sealed with nail varnish.




The stem for both slides was soaked in 95% alcohol for around three hours before mounting. I will report tomorrow on the first tests (now two days apart) on how they are doing.

[Hobbyst46]

The stem for both slides was soaked in 95% alcohol for around three hours before mounting. I will report tomorrow on the first tests (now two days apart) on how they are doing.

I am no authority on sections; just that my good results with fructose were obtained on fresh cuts, directly from the plant to a short rinse with DW and straight to the slide, not ones that were pre-soaked in alcohol.
I thought that strong syrupy sugar solutions are not attacked by microbes and mold, so perhaps alcohol was not needed.

[Roldorf]

Hi Hobbyst46

Ahha never thought of that. I will have to try a section without soaking in alcohol and see how that does. Another one for tomorrow.

[MicroBob]

Hi together,

for mounting in Euparal a proven standard procedure would be to keep the material in AFE mix (http://www.aeisner.de/rezepte/fixant2.html) for a while or even for longer periods. This is said to fix the biological processes and conserve the material in natural state. 96% cleaning alcohol is thought to be an acceptable alternative in a pinch.
I'm not sure how this can be translated to a mounting in water soluble fructose. Probably it is best to completely replace the AFE with demineralized water before the start of the mounting process.

Only because it is proven the AFE method will not be the only one that works. Walter Dioni e.g. wrote about using boiling water to fix specimens.

When making jam 50% fructose content is said to be not enough as the only conservative, contrary to normal sugar. I don't know how much this improves towards higher fructose contents in the mountant.

BTW: I have just received Walter Dionis book and expect to find a lot of useful information in it.

Bob

[Roldorf]

Just prepared a fructose slide without soaking in alcohol.