Q: I ordered the Streptavidin-ZAP (Cat. #IT-27) and had my antibody biotinylated a couple of months ago. I am ready to begin the first round of experiments to determine the concentration needed for the secondary. How much of the biotinylated antibody should I put to combine with the streptavidin for intravitreal injections? Can you please send me a protocol for how to determine the ratio of primary to secondary?
A: Streptavidin-ZAP should be mixed with the biotinylated material at an equimolar concentration. The Streptavidin-ZAP you ordered should have included a data sheet which gives the protein concentration and molecular weight, which you would use to determine the molar concentration. We have a calculator page on our website which can help with this if needed.
Listed below is a publication using Streptavidin-ZAP combined with a biotinylated antibody being used in intravitreal injections. The reference describes in detail the quantities they tried. You can also browse references on our site to see how scientists use ATS products to accomplish their research goals and publish in respected journals.