Simultaneous determination of follicle stimulating hormone and luteinising hormone using a multianalyte immunosensor

A technique is described for constructing a multianalyte immunosensor for the quantitative determination of the human gonadotrophin hormones follicle stimulating hormone (FSH) and luteinising hormone (LH). The assay is a based upon the electrochemical detection of two horseradish peroxidase labelled antibodies using a ferrocene mediated system. The detection limits (3σ) were 2.1 U l−1 FSH and 1.8 U l−1 LH. There was negligible cross reactivity. Results obtained with the biosensor showed a good correlation with those obtained using an established clinical diagnostic technique based upon dissociation-enhanced lanthanide fluorometric immunoassay. This is the first report of an electrochemical multianalyte immunosensor for high molecular weight analytes.