All dyes have characteristic spectra in visible range. Quantitative analysis in solution is simple as for other dyes. Quantification in or on particles is much more tricky.

Conc of dye can be measured by using UV-vis spectrophotometer after knowing the specific wavelength for particular dye then you can measure the concentration.

Thank you Titus Sobisch and Sebastian L. B. König and Raesh Muhammad. You all made it clear to me. I was not sure if the usual UV-spectrophotometric method is also applicable to fluorescent dyes.

Hi Rehman,

If you need further help, please feel free to ask.

Regards

raeesh

Mubashar Rehman Hello Mubasher,

I have the same problem I wanted to know if you were able to use UV for quantification of the fluorescent dyes in the solution?

Dear Navideh,

you have to build your own calibration line.

This means recording the UV-Vis absorption spectra of your dye at different concentrations; then you can plot absorption maximum vs concentration, you'll get a line according to Lambert and Beer's law (slope will correspond to your molar extinction coefficient).

Thanks to this calibration you'll be able to find out the concentration of an unknown solution of the same dye.