Concerning IHC zinc fixative supplier/source
FIRST, Z-Fix from Anatech is NOT the formalin free Beckstead Zinc fixative (BD Pharmingen) commonly used for rodent and human CD/leukocyte marker work. Kathy wrote: I am searching for a vendor to supply IHC Zinc fixative. Not zinc formalin. It's ALMOST like the BD Pharmingen IHC zinc fix, but contains Zinc acetate too. We do not want to make it up in house though....it contains calcium acetate, zinc acetate, zinc chloride and tris buffer. I have searched the 'net and all I garnered was a head ache, there are so many variations of zinc fixatives, and none are what we need. Any help would be appreciated. Thank you! ***************************************************** Kathy, What you are looking for is the true, original formulation of the Beckstead Zinc Tris buffer (non-formalin) fixative. The BD Biosciences Zinc Fixative (Formalin Free) Cat# 552658 technical data sheet cites his publication, but the MSDS shows zinc acetate is not part of the reported toxic substances. If they are citing Beckstead, they are more than likely using his original formulation (see below) but to make sure this is absolutely correct, you should contact their technical services about this. They have zinc in the recipe from zinc chloride and maybe they have modified the formulation so that it works as well or better from the original without the zinc acetate. Making it up in house was not difficult when we tried the fixative. Zinc Fixative (JB Fixative or ZSF) 0.1M Tris Buffer, pH 7.4 Tris Base -------------------------------- 12.1 g (TRIZMA) 1N HCL ----------------------------------- 81.5 ml Distilled water -------------------------- 900 ml Mix to dissolve. Adjust pH to 7.4 Zinc Fixative Calcium Acetate ---------------------- 0.5 g Zinc Acetate -------------------------- 5.0 g Zinc Chloride -------------------------- 5.0 g 0.1M Tris Buffer made above ------ 1000 ml Mix to dissolve. The final pH will be approximately 6.5-7.0. Do not readjust the pH, as this will cause the zinc to come out of solution. Store Zinc Fixative at room temperature. Fix tissues for 24 to 48 hours. Fixation longer than 48 hours may make the tissue brittle and difficult to cut. As far as I know, there is no other company in the US that makes up this fixative - a unique one of a kind fixative not commonly used by many labs except maybe research facililites. I think it is available from sources in Europe, but can't be sure of exactly what they are selling from publications I have read. Sorting that out was not fun. Personally, I would trust the BD Bioscience Zinc fixative (formalin free) simply because they do cite Beckstead's publication. I know that Ray Koelling, now at Phenopath, has used this fixative in the past, and he may have purchased it from BD. Hopefully he is looking in and can address your problem. He has been CC'd with this message. Good luck and hope your headache goes away - Gayle M. Callis _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet