This immunohistochemistry protein blocker is specifically designed for immunohistochemical staining where detection occurs using an immunoenzymatic reaction with substrate, i.e. peroxidase (HRP) with diaminobenzidine (DAB). This product specifically inhibits non-specific staining of IHC detection reagents. It may be used on various specimens, including cultured cells and primary tissue to lower background staining. Optimum performance is achieved using this product undiluted. However, Immunohistochemistry Protein Blocking Buffer can often be diluted 1:1 in TBS without a significant loss of performance. This immunohistochemistry protein blocker consists of proprietary blocking agents and stabilizers prepared using ultra pure reagents dissolved in pharmaceutical grade water (WFI). The buffer is pH adjusted to pH 7.6.