Hello Santanu, Why dont u try DSP - di thiobissuccinimydal propionate. You can get a few technical references from the PierceNet website. Its a commonly used immobilizing agent onto gold. Best wishes, Samir Samir Kagadkar Department of Electrical Engg IIT Bombay > I need help to find a suitable thiol reagent to form a > coupling between goat anti-mouse IgM (miu chain) and > bare gold surface. It would be great if anybody can > tell me how to select thiol reagents in this kind of > situation. I am having problem in immobilizing this > antibody on the gold surface . > Santanu Chandra