BrdU Cell Proliferation Assay Halogenated nucleotides such as the pyrimidine analog bromodeoxyuridine (BrdU) can be used to label nascent DNA in viable cells. During the process of DNA replication, BrdU can replace thymidine and incorporate into the synthesized DNA of actively dividing cells. Since this BrdU reagent does not cross react with endogenous DNA, cell proliferation thus can be reflected in the extent of BrdU incorporation by determining the intensity of absorbance of the final reaction. The BrdU cell proliferation assay is a versatile and convenient method to quantify cell proliferation. In the BrudU cell proliferation assay, cells are cultured with labeling medium that contains BrdU and BrdU is incorporated into de novo-synthesized DNA as a substitute for thymidine, which could label proliferating and daughter cells until it is diluted out through multiple rounds of cell division. Cells proliferation can be labeled by this method and BrdU can be detected by specific monoclonal antibodies. There are several kinds of antibodies that can be used to recognize the bound detection antibody. To achieve a better result, HRP substrate TMB is added to develop color and the magnitude of the absorbance for the developed color is proportional to the quantity of BrdU incorporated into cells. Cell proliferation can be directly indicated by the quantity of BrdU that is incorporated into cells. The BrdU cell proliferation assay has been widely applied in the study of cell proliferation and this method can also be used to assess cell proliferation in vivo. The BrdU cell proliferation assay is a rapid, simple and high sensitive method to assess cell proliferation. With the high resolution data of cell proliferation acquired from this assay, a further understanding of the mechanisms of cell proliferation can be achieved and many molecular mediators that could regulate cell proliferation can be identified including hormones, signaling components and transcriptional factors. Custom service is also available. This assay can be modified to generate a more targeted result according to the purpose of the research.