Re: LACMOID RE: OOCYTES - HELP!!!!

From:Geoff McAuliffe <mcauliff@UMDNJ.EDU>

Bruce Abaloz wrote:

> Dear Histonetters,
>
> Can anyone give me any suggestions on how to prepare a lacmoid solution for ooctye staining?
>
> We found it very difficult to get lacmoid crystals, and the batch we finally got our hands on is very old.  I needed to prepare a 1% lacmoid solution and placed 1g of lacmoid crystals in 45% acetic acid and left it on a stirrer/hot plate for 2 hours at a moderate heat.  When I filtered it there was still a large amount of crystal undissolved (about half), yet a reasonable amount of colour in the solution.  The undissolved crystal was more grey in colour than they grey/burgundy of the original crystal.
>
> Does anyone know if this is an appropriate method of preparation?  I can't believe my solution is a 1% solution if there is undissolved crystal?
>
> BRUCE ABALOZ
> HISTOLOGIST
> DEPARTMENT of ZOOLOGY              *  PH:    +61 3 83446282
> The UNIVERSITY of MELBOURNE        *  FAX:   +61 3 83447909
> Parkville, Victoria.3010           *  EMAIL: b.abaloz@zoology.unimelb.edu.au
> AUSTRALIA.

Dear Bruce:

    The 4th edition of "Staining Proceedures" mentions lacmoid only as a stain for plant material. The proceedures I looked at called for 0.25% lacmoid in 30% ethanol with a few ml of 1% NaHCO3 added. That solution would be alkaline, yours is acidic. The 10th edition of the "Microtomists Vade-Mecum" calls for 5 mg in 10-15 ml of water with the pH adjusted to 8 with ammonia. Again, a stain for plant material. So perhaps your solution is too concentrated and the wrong pH?
    Hope this helps.

Geoff
--
**********************************************
Geoff McAuliffe, Ph.D.
Neuroscience and Cell Biology
Robert Wood Johnson Medical School
675 Hoes Lane, Piscataway, NJ 08854
voice: (732)-235-4583; fax: -4029
mcauliff@umdnj.edu
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