Guidance with stains.

Re: Guidance with stains.

Postby admin » Tue Jun 08, 2010 9:12 am

Could I just remind followers of this thread of 2 fairly relevant pieces of information:

All of the stains discussed, plus a very comprehensive range of others, are available to ABFG members as part of their membership entitlement. The stains are not provided free of charge, but the cost is non-profit based and therefore very economical. All are made up in the recommended solution strengths, and are delivered to your door. The service is only available to Association members because we are not a trading company. Precipitation of congo red, by the way, is often attributable to contaminated material and we would not advocate purchasing dry stain through a high street chemist because of the absence of quality control. The powders sold on the high street can be of commercial grade only. Congo red in solution should last for several years in perfectly satisfactory state. I am using a batch here that we made up over 4 years ago!

We have run a series of extensive articles in recent time, in the Forayer, on the practical application of stains and reagents. These can be provided to ABFG members as PDF downloads, though it may take a week or more to organise the service if we are otherwise busy. I will see if we can also get them organised to view on the ABFG web pages.

Michael Jordan
Forum moderator
Site Admin
Posts: 532
Joined: Wed Jan 07, 2009 11:43 pm

Re: Guidance with stains.

Postby Leif Goodwin » Tue Jun 08, 2010 9:52 pm

Hello Andreas

If you have the time, I would greatly appreciate brief comments from you describing how you get tissue samples, perhaps as part of your longer answer. I find myself using needle nosed tweezers or a razor blade, and I recently bought some Japanese kitchen knives which I will try. People tell me you can shave with the kitchen knives that are that sharp. I still consider the ability to isolate tissue as one of the many weak spots in my technique.


Andreas Gminder wrote:Hello,

the usual reciepts for Congo Red always talk about a saturated solution, be it in water, in NH3 or in SDS. The problem is, that when the saturated solution gets colder, the congo red starts falling out. Same is true for the solution in NH3, because with every opening of the bottle some NH3 vanishes, and soon the solution becomes over-saturated and falls out. You can fix that by warming your bottle a little bit, so that the solution is no longer oversaturated and gets clear again. If you mix your solution not saturated, you get worse results, so this is no good idea.

As I feel that there is a need for explanation about use of stains, I will prepare a longer answer in a separate thread.

best regards,
Fungi and Nature Photography:
Leif Goodwin
Posts: 1080
Joined: Mon Feb 02, 2009 5:41 pm


Return to Microscopy

Who is online

Users browsing this forum: No registered users and 1 guest