fluorescein

noun

fluo·​res·​ce·​in flu̇-ˈre-sē-ən How to pronounce fluorescein (audio)
flȯ-
: 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 analysis of the water samples revealed the presence of a non-toxic tinting agent called fluorescein, which is most commonly used in eye tests. Ananya Bhattacharya, Quartz, 30 May 2023 Officials took samples at different depths in the water to determine how much fluorescein sunk to the bottom of the canal. Sarah Kuta, Smithsonian Magazine, 31 May 2023 Testing showed the presence of fluorescein, an environmentally harmless dye that can be used to locate blood at crime scenes and diagnose eye injuries. Sarah Kuta, Smithsonian Magazine, 31 May 2023 Researchers dumped a dye, fluorescein, into the wells and monitored the marine waters along the beaches. Warren Cornwall, Science | AAAS, 23 Apr. 2020 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, 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, 18 Dec. 2018 Our doctor placed yellow drops containing fluorescein sodium in his eye. Dan Olson, WIRED, 29 Sep. 2008

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fluorescein.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1871, in the meaning defined above

Time Traveler
The first known use of fluorescein was in 1871

Dictionary Entries Near fluorescein

Cite this Entry

“Fluorescein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluorescein. Accessed 24 Jun. 2024.

Medical Definition

fluorescein

noun
flu·​o·​res·​ce·​in -ˈes-ē-ən How to pronounce fluorescein (audio)
: 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)

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