Bimetallic chips for a surface plasmon resonance instrument

In this work we have replaced a commonly used Au film with an Au/Ag bimetallic film working as the sensing chip in the commercial surface plasmon resonance (SPR) instrument, Biacore 3000. The bimetallic chip gives out sharper SPR dip than that by the chip made of an Au film. The applicability and stability of the bimetallic chip on the Biacore 3000 are tested by real-time monitoring of biological coupling processes between sulfamethoxazole (SMX) and anti-SMX, which is useful in rapid detection of contaminations in food products. The bimetallic chip performs stably in 6 times' usage and regeneration. Our experiment is helpful to push the bimetallic film into real applications in commercial SPR instruments.