Dear Scott,
 

 >Scenario #1   A rep. comes into your lab with 10-20
 >lbs of new paraffin and would like for you to try it.
 >What would you be thinking?
 
 >Scenario #2   Instead of 10-20 lbs of paraffin, the
 >rep. has about 7 blocks already embedded with their
 >new paraffin and would like for you to try it.
 >What would you be thinking?

Frst step:
Melt some of the wax and make a block out of it. Try to section it.
Caveats: Some waxes seem to need to "mature" (ie heated for some 
12-24 hours) before use in embeding.

Second step:
Process paired slices of liver, spleen, uterus, colon, brain and 
lymph node to infiltration stage. Infiltrate one of each pair in 
trial wax and current preferred wax for 2 hours, changing once.
Embed in relevant wax.
Gauge ease of sectioning especially uterus, 2um sections of lymph 
node, 6-7um sections of brain,  any folding of the muscle layers of 
the colon, any cracking of the spleen sections, continuity of 
hepatocytes in liver.

Third Step:
Does wax dissolve easily in the deparafinisation solutions (xylene 
or citric-type oils).
Does the wax interfere with any stains (Retic, trichrome, mucin etc) 
or a selection of IPX stains (eg Vimentin, Keratin, LCAg).

A good project for junior staff??


Tony Henwood
Senior Scientist
Anatomical Pathology
Royal Prince Alfred Hospital
Sydney, AUSTRALIA

http://www2.one.net.au/~henwood
http://www.pathsearch.com/homepages/TonyHenwood/default.html