Most formalin-fixed tissues require an antigen retrieval step before immunohistochemical staining. Although fixation is essential for the preservation of tissue morphology, this process can also have a negative impact on IHC/ICC detection. Fixation can alter protein biochemistry such that the epitope of interest is masked and can no longer bind to the primary antibody. Methylene bridges formed during fixation cross-link proteins and mask antigenic sites. Antigen retrieval methods break these methylene bridges and expose antigenic sites, allowing antibodies to bind. The two methods for antigen retrieval are heat induced epitope retrieval (HIER) and enzymatic retrieval.

We offer a range of HIER Retrieval Buffers with different pH and packaging (ready-to-use or concentrated) to find the one that best suits your protocol.