When antibodies are purchased concentrated, they should undergo an antibody titering or dilution panel. This dilution panel is performed to determine the highest dilution of that antibody which results in the greatest specific staining, with little to no background, under the selected method’s test settings that will be used. Usually, the manufacturer suggests a starting dilution. Then a series of dilutions below and above the suggested dilution are performed. For example the manufacturer suggests that the optimal dilution of a particular antibody is 1:200. You would then perform a series of dilutions including 1:50, 1:100, 1:200, 1:300, and 1:500. Performing the dilution panel in this manner gives you a range of staining/non-staining dilutions that will help decide on the highest dilution that will give the best specific staining without background. If all of the dilutions stain intensely, an additional dilution panel is recommended with higher dilutions. On the reverse side, if all of the dilutions in the first panel do not stain, then lower dilution panel is recommended.