Hi,

Have you thought about using a water-soluble wax? Polyethylene glycol
mixtures are/were available. Floating out can be a problem if the block is
made up of small pieces.

Cheers

Steve


                                                                                                                                                 
                    Roy Ellis                                                                                                                    
                                                                               
                    sa.gov.au>              cc:     Histonet                                                       
                                            Subject:     RE: Embryo Processing                                                                   
                    07/08/2002 00:30                                                                                                             
                                                                                                                                                 
                                                                                                                                                 




Keith
The only solvent-free, and relatively safe way to dehydrate tissues that I
am aware of is using freeze-drying. Tissues are rapid frozen at about -160
degrees C and are subsequently dessicated at slightly higher temepratures.
Once dried the tissues are embedded directly into wax, then cut in the
usual
way. It was a method used extensively in the early days of developing
histochemistry and promoted as the only way to ensure accurate retention
and
localisation of tissue components. If you can get your hands on a copy of
"Histochemistry, Theoretical and Applied by AG Everson Pearce, Published by
Churchill, 2 volumes, the volumes contain extensive descriptions of the
equipment and techniques. I have the third edition published in 1968.
Regards
Roy Ellis

mailto:roy.ellis@imvs.sa.gov.au

> -----Original Message-----
> From: Keith Rogers [mailto:krogers@ncifcrf.gov]
> Sent: Tuesday, 6 August 2002 09:45 PM
> To: histonet@pathology.swmed.edu
> Subject: Embryo Processing
>
>
> Dear Histonetters,
>
> We routinely process mouse embryos from day 7dpc and up. We have
> a request
> to process embryos that have been pre-stained with an alkaline phosphate
> substrate - INT BCIP. This substrate is alcohol soluble. Routine paraffin
> processing, no matter how short, reduces or eliminates the staining. Can
> anyone suggest alternative dehydrants that I can use? There are some
> methods that use highly toxic solvents, we would like to avoid these is
> possible.
>
> Many thanks,
>
> Keith Rogers
> SAIC Frederick
> (301-846-5190)
>