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Metal particle-enhanced fluorescent immunoassays on metal mirrors

Department of Cell Biology and Anatomy, The University of Calgary, Calgary, Alberta, Canada
Analytical Biochemistry (Impact Factor: 2.31). 05/2007; 363(2):239-45. DOI: 10.1016/j.ab.2007.01.030
Source: PubMed

ABSTRACT We present fluoroimmunoassays on plain metal-coated surfaces (metal mirrors) enhanced by metal nanoparticles (silver island films [SIFs]). Metal mirrors (aluminum, gold, or silver protected with a thin silica layer) were coated with SIFs, and an immunoassay (model assay for rabbit immunoglobulin G or myoglobin immunoassay) was performed on this surface using fluorescently labeled antibodies. Our results showed that SIFs alone (on glass surface not coated with metal) enhance the immunoassay signal approximately 3- to 10-fold. Using a metal mirror instead of glass as support for SIFs results in up to 50-fold signal enhancement.

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