Table 2.

Control experiments to be done once per primary antibody to test its specificity

Suppose you are using 3 primary antibodies , which happen to be an IgG raised in rabbit, an IgM from mouse and an IgG from guinea pig. Obtain peptides for preabsorption and/or non-specific immunoglobulins of the same type and species, and label 3 slices each with them as follows.

Primary antibody (Ab)	Peptide or immunoglobulin	No. of slices to label
IgG rabbit	Label after preabsorbing with peptide to Ab	3
IgM mouse	Label after preabsorbing with peptide to Ab	3
IgG guinea pig	Label after preabsorbing with peptide to Ab	3
IgG rabbit	Label with unspecific IgG rabbit	3
IgM mouse	Label with unspecific IgM mouse	3
IgG guinea pig	Label with unspecific IgG guinea pig	3