blocking buffer containing BSA and cross reactivity - (Mar/18/2012 )

Could BSA present in the blocking buffer cross react with a mouse-anti human Ig detection antibody ? Thank you

very unlikely, why?

Yes highly likely if the BSA is not IgG free and if the mouse anti-human IgG shows cross reactivity with bovine IgG.

There are a number of solutions to this problem.

Use IgG free BSA. Use an alternative non mammalian blocking solution. Use a mono detection regent with confirmed lack of cross reactivity with bovine IgG. Use a bovine serum protein cross absorbed polyclonal anti-human IgG reagent. Jackson, Bethyl, or Southern Bio are good vendors for these.