A micro amperometric immunosensor immobilized with electropolymerized staphylococcal protein a for the detection of salmonella typhimurium

In this paper, a micro amperometric immunosensor based on Micro-Electro-Mechanical Systems technology for the detection of Salmonella typhimurium (S. typhimurium) was constructed by immobilizing a polyclonal antibody (the bio-molecular recognition element) onto the surface of polypyrrole(PPy)/staphylococcal protein A(SPA) modified Pt electrode. Pyrrole doped with SPA was co-electropolymerized onto the working electrode surface by cyclic voltammetry in 10 minutes for orientation-controlled immobilization of salmonella capture antibodies. S. typhimurium with the concentration of 102 cfu/ml could be detected by this immunosensor with a controllable and convenient manipulation to effectively modify the sensing surface more rapidly with less consumption of reagent (10 muL), which showed the good property of the sensor. It is potential to develop a micro biosensor that can be used for convenient, accurate, cost-effective and real-time sensing of pathogens in food products.