  Although fluorescence is the prevailing labeling technique in biosensing
applications, sensitivity improvement is still a striving challenge. We show
that coating standard microscope slides with nanoroughened silver films
provides a high fluorescence signal enhancement due to plasmonic interactions.
As a proof of concept, we applied these films with tailored plasmonic
properties to DNA microarrays. Using common optical scanning devices, we
achieved signal amplifications by more than 40-fold.
