This CDC25C (phospho Thr48) Cell Based ELISA Kit allows for the detection of CDC25C (phospho Thr48) and the effects that certain stimulation conditions have on CDC25C (phospho Thr48) expression in different cell lines. Qualitative determination of CDC25C (phospho Thr48) concentration is achieved by an indirect ELISA format. In essence, CDC25C (phospho Thr48) is captured by Anti-CDC25C (phospho Thr48) Antibodies while Dye 1-conjugated and Dye 2-conjugated secondary antibodies bind the Fc region of the primary antibody. Through this binding, the dye conjugated to the secondary antibody can emit light at a certain wavelength given proper excitation, hence allowing for a fluorometric detection method. A monoclonal antibody specific for human GAPDH is included to serve as an internal positive control in normalizing the target RFU values. Anti-CDC25C Antibody is also included for normalization purposes. The RFU values obtained for the non-phosphorylated target can be used to normalize the RFU value for the phosphorylated target.