Fluorescence background limited

Funk et al. have used a low-pressure mercury lamp without filter to liberate inorganic tin ions from thin-layer chromatographically separated organotin compounds these were then reacted with 3-hydroxyflavone to yield blue fluorescent chromatogram zones on a yellow fluorescent background [22]. Quantitative analysis was also possible here (XoK = 405 nm, Xji = 436 nm, monochromatic filter). After treatment of the chromatogram with Triton X-100 (fluorescence amplification by a factor of 5) the detection limits for various organotin compoimds were between 200 and 500 pg (calculated as tin). 

On excitation with long-wavelength UV light (X = 365 nm) ketoprofen (hcf 35-40) and flurbiprofen (h/ f 50-55) appeared as yellow or blue fluorescent chromatogram zones on a pale blue fluorescent background. The detection limits of, for instance, flurbiprofen were 10 ng subtance per chromatogram zone. 

One of the limitations associated with the use of fluorogenic dyes as labels for nucleic acids is the relatively high background fluorescence intensity in solution. This problem can be ameliorated by the use of asymmetric cyanine dyes. Another approach that can achieve low fluorescence background is based on the use of FRET pairs. If the acceptor and donor are in close proximity to... 

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