Gimme 5! Block before or after Ag retrieval. If it's Pwax sections make a 1/10 dilution of 100vols ( ~30%) H2O2 in Dist.water. Block for 15mins. Methanol is not neccessary...imho. Carl Carl Hobbs Histology Manager Wolfson CARD School of Biomedical Sciences Kings College London Guys Campus London SE1 1UL Tel: 020 78486813 Fax: 020 78486816