Magnetoelastic biosensors: Corrosion protection of an FeNiMoB alloy from alkoxide precursors

Mass-sensitive biosensors developed from magnetoelastic alloys have been increasingly used for pathogen detection in food. To protect the magnetoelastic alloys from the corrosive medium a gold layer has been used. In this paper, it was propose two different films based upon alkoxide precursors as a new alternative as coating for biosensors. The films are easily applied on the Metglas® 2826MB3 substrate by dip-coating. It was used the alkoxide precursors 1,2-Bis(triethoxysilyl)ethane (BTSE), tetraethoxysilane (TEOS) and 3-(Trimethoxysilyl)propyl methacrylate (MAP). The film developed from BTSE was thick and irregular. The film developed from the TEOS-MAP precursors combined was found to be more compact and uniform, with good adherence to the substrate, and showed a higher electrochemical performance. Therefore, the TEOS-MAP film is the suitable as a protective coating for the Metglas®2826MB3, because this film assures the integrity of the biosensor in an aggressive environment.