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Looking for a specific dye

  1. Aug 4, 2013 #1
    Hi folks,

    I'm looking for a dye that absorbs strongly around the 490nm range. Sort of a red/orange I guess. I cannot find a lot of data on absorbency by dye manufacturers, will begin emailing them shortly. Key word searches tend to bring up dye absorbency in relation to materials not light

    The purpose of this is to create a standard for a urine sampling system that uses UV/VIS spectrophotmetry.
  2. jcsd
  3. Aug 5, 2013 #2


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    This is the uv-vis spectrum of beta-carotene (the orange compound in carrots). You can see an absorption peak between 400 and 500 nm. Fluoresceine has an an absorption peak in that area too, but it is a fluorescent dye which might make it unsuitable for this purpose.

    I hope this helped.
    Last edited by a moderator: May 6, 2017
  4. Aug 5, 2013 #3
    That did, thank you.
  5. Aug 7, 2013 #4
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