fluorescein

noun
fluo·​res·​ce·​in | \ flu̇-ˈre-sē-ən , flȯ-\

Definition of fluorescein

: a yellow or red crystalline dye C20H12O5 with a bright yellow-green fluorescence in alkaline solution

Examples of fluorescein in a Sentence

Recent Examples on the Web

The polyacrylate was then bathed in molecules of fluorescein, an orange dye with a yellow-green fluorescence that's commonly used as a scientific marker. David Grossman, Popular Mechanics, "Honey, I Shrunk Everything: MIT Scientists Can Shrink Objects to the Nanoscale," 18 Dec. 2018 With the fluorescein in place, scientists then add an acid that hinders the negative charges in the polyacrylate gel. David Grossman, Popular Mechanics, "Honey, I Shrunk Everything: MIT Scientists Can Shrink Objects to the Nanoscale," 18 Dec. 2018 Our doctor placed yellow drops containing fluorescein sodium in his eye. Dan Olson, WIRED, "Ignorance Was Bliss: Taking a Lego to the Eye," 29 Sep. 2008

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fluorescein.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fluorescein

1871, in the meaning defined above

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Last Updated

15 Feb 2019

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Time Traveler for fluorescein

The first known use of fluorescein was in 1871

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More Definitions for fluorescein

fluorescein

noun
flu·​o·​res·​ce·​in | \ -ˈes-ē-ən \

Medical Definition of fluorescein

: a yellow or red crystalline dye C20H12O5 with a bright yellow-green fluorescence in alkaline solution that is used as the sodium salt as an aid in diagnosis (as of lesions and foreign bodies in the cornea or of brain tumors)

More from Merriam-Webster on fluorescein

Britannica.com: Encyclopedia article about fluorescein

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