Monoclonal antibodies specific to six histidine tags can greatly improve the effectiveness of several different kinds of immunoassays, helping researchers identify, detect, and purify polyhistidine fusion proteins in bacteria, insect cells, and mammalian cells. However, since 6XHis-tag is poorly immunogenic, it needs to be conjugated to KLH or some other carrier as an immunogen. After hundreds of selection cycles, researchers at GenScript successfully isolated an antibody against His-tag. THEᵀᴹ His Tag Antibody, mAb, Mouse (subtype IgG1) has very high affinity. Tests performed at GenScript show that the antibody can also recognize 4xHis- and 5xHis-tags. This means that even if the 6xHis-tag is only partially exposed, it will still be recognized and bound by this antibody. THEᵀᴹ His Tag mAb is produced from mice ascites and purified by protein A affinity column. This antibody recognizes native as well as denatured forms of synthetic polyhistidine and polyhistidine-tagged fusion proteins. The product reacts with fusion proteins expressed in bacteria, insect cells, and mammalian cells. THEᵀᴹ His Tag mAb recognizes His tags placed at N-terminal, C-terminal, and internal regions of fusion proteins. THEᵀᴹ His Tag mAb can be used in Western blot analyses, Dot blot analyses, ELISA, immunofluorescent staining, and flow cytometry of cultured cells.