Metal-Enhanced Fluorescence (MEF): Physical characterization of Silver-island films and exploring sample geometries

In this study we have analyzed metal-enhanced fluorescence (MEF) effects from different density Silver-island films (SiFs) and the effects of sample geometry on the observed enhancement of fluorescence (EF). It is shown that silver islands grow exponentially with SiF deposition time (DT < 5 min), optical density of SiFs almost linearly depends on DT; electrical conductivity is zero. At DT > 5 min, silver islands merge, exhibiting a sharp increase in electrical conductivity. It has been shown that the newly proposed SiF sample geometry exhibits higher EF values than the commonly used in MEF studies SiF–SiF sample geometry. The SiF–glass geometry demonstrates high sensitivity for surface immunoassays, a growing application of metal-enhanced fluorescence.