title: Fluorescence spectral properties of cyanine dye-labeled DNA oligomers on surfaces coated with silver particles.
abstract: We examined the fluorescence spectral properties of DNA oligomers, labeled with Cy3 or Cy5, when bound to quartz surfaces coated with metallic silver particles. Prior to binding of labeled DNA the surfaces were treated with polylysine or 3-aminopropyl triethoxysilane or were coated with avidin for binding of biotinylated oligomers. The fluorescence intensities were increased an average of 8-fold on these surfaces. Despite the increased emission intensity, the photostability of the labeled DNA was the same or higher on the silver-coated surfaces than on the uncoated slides. The time-integrated intensities, that is the area under the intensity plots with continuous illumination, increased an average of 6-fold. In all cases the lifetimes were dramatically shortened on the silver particles, indicating an over 100-fold increase in the radiative decay rates. These results suggest the use of substrates containing silver particles for increased sensitivity of DNA detection on DNA arrays.
authors.affiliation: Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, MD 21201, USA.
authors.forename: Joanna
authors.initials: J
authors.lastname: Malicka
authors.forename: Ignacy
authors.initials: I
authors.lastname: Gryczynski
authors.forename: Jiyu
authors.initials: J
authors.lastname: Fang
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Lakowicz
mesh_terms: D001360:Avidin / Q000737:chemistry; D001483:Base Sequence; D001710:Biotin / Q000737:chemistry; D002232:Carbocyanines / Q000737:chemistry*; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D009841:Oligonucleotides / Q000737:chemistry* / Q000235:genetics; D011107:Polylysine / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013499:Surface Properties; D013997:Time Factors
chemical_list: D002232:Carbocyanines; D009841:Oligonucleotides; C089187:cyanine dye 3; C085321:cyanine dye 5; D001360:Avidin; D011107:Polylysine; D012834:Silver; D001710:Biotin; D004247:DNA