Elsie Kok in Singapore asks:

>>Is anybody out there using denatured alcohol to process tissue? Do you have 
any problem with sectioning and staining (both H&E and IHC)? We have started 
to use the denatured alcohol for a couple of weeks but have problem with 
sectioning and staining.<<

You may be using the wrong denatured alcohol. There are many formulas for 
denaturing alcohol - rendering it unfit to drink - and these denaturing 
formulas are decided by governments. Singapore's formulas may well be 
different from the USA's. Check your container labels, and ask your supplier.

In histology, the usual denatured alcohol is referred to (in the USA at 
least) as "reagent alcohol". Its US government specified (Bureau of Alcohol, 
Tobacco, and Firearms - under Treasury) denaturing formula is called "S3DA 
modified". The mixture is 90% ethanol, 5% methanol, and 5% isopropanol. - 
Occasionally one encounters a different denaturant, methylisobutylketone 
(MIBK), but this mixture smells so bad that histologists do not willingly use 
it.

I have seen a situation where a laboratory manager ordered denatured alcohol 
that was denatured with acetone. It worked reasonably well for processing, 
but of course the acetone stripped the eosin right out of the H & E stain.

Bob Richmond
Samurai Pathologist
Knoxville, Tennessee USA