[Histonet] Plastic sectioning basics

[Jorge Tornero]

Dear Pamela and all,

I thought that the "dance" (wich has happened to me a very few times)
was caused by the turbulence inside the container of water, very small
but enough to move such a small thing like a cut.

I have other question concerning to the maximum width of the bolck to
be cut. And also, wich molds do you use for your blocks. Actually we
use molding cup trays from ems (ref. 70176-10  	6x12x5mm) but we'll
try to use other, the same kind but 13x19x5mm. I think it would be too
wide and the cutting will we bad but I'll appreciate your opinions.

Do someone have experience staining GMA with H&E? I have experienced
some problems, and a big one is coming, because we are going to begin
to use an autostainer XL from leica to do so. if someone has
experience on it, please tell.

Thank you very much.

Jorge Tornero
IEO - Cadiz
Spain



2005/5/19, Pamela A. Marcum <pmarcum <@t> vet.upenn.edu>:
> Hi Jorge,
> 
> There really is no universal angle for plastics.  The block size and type of
> microtome and plastic are all different.  I have always experimented until it
> felt right and the sections were coming off well.  As for water -  the product
> you are using is a gylcol methacrylate base and will react with water.  If you
> take a section off the knife with forceps and place it on a water bath or
> container of water most of the time it will literally dance around the surface.
>  I have always picked GMA up from a water bath or container to allow this to
> happen.  If I placed on a drop of water on a slide it would go the edge and
> just crumple up.  You can add alcohol to the water bath or container at 50 ot
> 60% and it will help stretch them as they dance.  Plastics are very different
> from paraffin and do not ribbon well as it is genreally one section at a time
> with patience.
> 
> The trick with water is used with methyl methacrylate MMA not GMA.  If I can
> assist your further or you have any questions please write me and I will
> attempt to help you in any way I can.
> 
> Best Regards,
>