Description
Combination of His-tagged proteins (Histidine-tagged proteins) and Ni-NTA (nickel-chelated nitrilotriacetate) is one of the techniques to immobilize proteins through a Ni-NTA SAM (self-assembled monolayer) formed on a gold coated substrate, which can be utilized for QCM (quartz crystal microbalance) or SPR (surface plasmon resonance) measurement. His-tagged protein binding method has advantages due to the following two reasons: denaturing risk of the immobilized proteins is low because of the site specific binding of the His-tagged proteins, and multiple use of the SAM plates can be achieved by imidazole or EDTA that cleaves the His-tag-Ni-NTA interaction.
The reagent solution for NTA-SAM formation on a gold-coated substrate can be easily prepared by dissolving NTA SAM-Formation reagent with ethanol, and prepared Ni-NTA-SAM can immobilize His-tagged protein efficiently