Biocare’s PromARKTM series introduces a 1-step horseradish peroxidase (HRP) polymer detection system for IHC of rat primary antibodies on mouse tissues, with minimal cross-reactivity. Rat HRP-Polymer, 1-Step (Mouse adsorbed) offers the convenience and sensitivity of a one-step polymer detection system that is biotin and avidin free. It is specifically formulated to improve specificity and reduce background staining on mouse tissues. The elimination of mouse IgG can be a persistent problem in achieving optimal staining of mouse tissues. In addition to the 1-step Rat HRP-Polymer (Mouse adsorbed) detection, Biocare offers reagents that may further reduce unwanted background staining. Adding XM Factor directly to Rat HRP-Polymer may further reduce background staining due to endogenous mouse IgG. Rodent Block M may also be used to reduce nonspecific background staining (see individual data sheets). Biocare has also developed Rodent Decloaker, an antigen retrieval solution, which is specifically formulated to reduce and/or eliminate non-specific background staining due to endogenous mouse and rat IgG. Temperature dependent antigen retrieval protocols can be performed using Biocare’s Decloaking Chamber (pressure cooker).