HCN4 Blocking Peptide (#BLP-PC052) is the original antigen used for immunization during Anti-HCN4 Antibody (#APC-052) generation. The blocking peptide binds and ‘blocks’ Anti-HCN4 primary antibody, this makes it a good negative reagent control to help confirm antibody specificity in western blot and immunohistochemistry applications. This control is also often called a pre-adsorption control.