Blocking Buffer is supplied by HiMedia. It is available in the form of a white coloured solution. Blocking buffer is used for the reduction of background interference during Western blotting, ELISA, immunostaining or other immunoassays. This buffer prevents non-specific binding of antibodies by binding to any open protein binding sites that do not have antibodies or antigen attached. Blocking Buffer enhances the sensitivity of any immunochemical applications by increasing signal-to-noise ratio and promoting specific binding of the primary antibody while minimizing non-specific interactions. This buffer comes as a ready-to-use solution of preformulated non-fat dry milk which is suitable for any immunochemical applications. Blocking Buffer contains 5% (w/v) non-fat powdered milk in Tris Buffered Saline (TBS) with 0.01% Antifoam A. It is advisable to store this product at 2-8C.

During the performance of various immunological experiments which are based upon enzyme conjugates that generate colorimetric or chemiluminescent signal, a blocking step is required to decrease the signal generated by non-specific binding of antibodies. The main purpose of the blocking reagent is to improve the sensitivity of an assay by reducing the background signal. For a particular immunoassay the concentration of blocking reagent has to be optimized because inadequate amount will result in excessive background and excessive can mask antibody-antigen interaction. As this Blocking Buffer contains non-fat powdered milk it is not recommended for avidin-based techniques because it contains some endogenous biotin. Blocking Buffer is used in Western blotting, ELISA, immunohistochemistry and other immunological detection methods. This buffer can be used as a diluent for antibodies to improve signal-to-noise ratios.