You can leave it in formalin for 48-72 hours without a problem, it might be better than fixing just for 4 hours, some say adequate formalin fixation takes at least 24 hours no matter the size of the sample.
Best regards, Patsy Patsy Ruegg, HT(ASCP)QIHC IHCtech 12635 Montview Blvd. Ste.215 Aurora, CO 80045 720-859-4060 fax 720-859-4110 www.ihctech.net www.ihcrg.org -----Original Message----- From: histonet-boun...@lists.utsouthwestern.edu [mailto:histonet-boun...@lists.utsouthwestern.edu] On Behalf Of Kalleberg, Kristopher Sent: Tuesday, November 24, 2009 4:51 PM To: histonet@lists.utsouthwestern.edu Subject: SPAM-LOW: [Histonet] Biopsy fixation Hello All, I have a simple fixation question. Typically when we process 3 mm skin biopsies we will fix in 10% NBF for 4 hours and then wash in PBS and then process over night into paraffin and then embed. If we are unable to immediately process the 3mm skin biopsies after 4 hr fixation what is the maximum time we can leave the biopsies in 70% alcohol before processing into paraffin? Is there a better reagent, such as PBS, other than alcohol to leave the biopsy in for a few days before tissue processing. Thank you in advance. Kris _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet