p21 Cip1 Colorimetric Cell-Based ELISA Kit

A cell-based ELISA kit from Assay Genie enables sensitive detection of p21 Cip1 protein directly in cultured cells without the need for lysate preparation. The assay uses an indirect ELISA format in which p21 Cip1 is captured by target-specific primary antibodies, with HRP-conjugated secondary antibodies binding the Fc region of the primary to drive a colorimetric reaction upon substrate addition. A monoclonal antibody specific for human GAPDH is included as an internal positive control for normalisation, and a Crystal Violet whole-cell staining step can be used to determine cell density so that absorbance values can be adjusted for plating differences.

The kit is reactive with Human, Mouse and Rat samples and is intended for use with adherent cells. Detection is colorimetric at 450 nm, with a dynamic range of > 5000 Cells, and the kit is stored at 4°C with 6 Months stability. It is suitable for measuring relative p21 Cip1 levels in cultured cells and for screening the effects of treatments, inhibitors (such as siRNA or chemicals) or activators on p21 Cip1 expression.

The target is encoded by the CDKN1A gene (Gene ID: 1026, UniProt ID: P38936), a cyclin-dependent kinase inhibitor regulated by p53 that mediates G1 cell cycle arrest.