Hi Tim, It is safe to consider "40% formaldehyde" to be a 100% solution, because that is the maximum amount of formaldehyde that will dissolve into an aqueous solution.
Happy Fixation, -Eric Eades Phenopath Laboratories Seattle, WA On Tue, Jul 24, 2012 at 12:36 PM, Tim Wheelock <[email protected] > wrote: > Hi Everyone: > > I had a few questions regarding Bielschowsky silver stains. > > (1) What adhesive (if any) or type of slide do you use for the stain? > (2) How do you clean the glassware? > (3) When diluting the 40% formaldehyde when making up the developer, do > you consider the 40% formaldehyde as 100% and then dilute it down by using > 1 part formaldehyde and 9 parts distilled water? > Or do you assume the 40% formaldehyde is 40% and then dilute it down > using 1 part formaldehyde and 3 parts distilled water? > (My protocol may have inadvertently changed from the first method to > the second; I am not sure.) > > By the way, I want to thank everyone for helping me solve the problem of > my Luxol Fast Blue staining the myelin too lightly. > I discovered that somehow, I had started adding twice the amount of acetic > acid to the Luxol staining solution as I should of. > (This protocol "drift", where a mistake can actually find its way into a > written protocol, can be a real problem in a lab, especially when working > for years by oneself, as I have) . > > But I also found that even reducing the acetic acid, while helping a lot, > did not completely fix the problem. > I needed to switch from staining the tissue for 2 hours at 60C to a full > over-night (why I never needed to switch times before is a mystery). That > did the trick beautifully. > The myelin is staining perfectly again. > > Thanks again, > > Tim Wheelock > Harvard Brain Bank > Belmont, MA > > > > ______________________________**_________________ > Histonet mailing list > [email protected].**edu <[email protected]> > http://lists.utsouthwestern.**edu/mailman/listinfo/histonet<http://lists.utsouthwestern.edu/mailman/listinfo/histonet> > _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet
