fluorescein

Or flu·o·res·ce·ine

[floo-res-ee-in, flaw-, floh-]

noun

Chemistry.

1. an orange-red, crystalline, water-insoluble solid, C 20 H 12 O 5 , that in alkaline solutions produces an orange color and an intense green fluorescence: used to trace subterranean waters and in dyes.

fluorescein

/ ˌflʊəˈrɛsɪɪn /

noun

1. an orange-red crystalline compound that in aqueous solution exhibits a greenish-yellow fluorescence in reflected light and is reddish-orange in transmitted light: used as a marker in sea water and as an indicator. Formula: C 20 H 12 O 5

fluorescein

1. An orange-red crystalline compound that exhibits intense fluorescence in alkaline solution. It is used in medicine for diagnostic purposes, in oceanography as a tracer, and as a textile dye. Chemical formula: C ₂₀ H ₁₂ O ₅ .

Word History and Origins

Origin of fluorescein¹

First recorded in 1875–80; fluoresce + -in ²

Example Sentences

On Monday, the authorities had an answer: Test samples of the water confirmed that the canal’s bright new hue was caused by fluorescein, a chemical often used find leaks during underwater construction.

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The chemical cause of the color change was found to be fluorescein, which is used professionally to trace water.

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He was injected with a bright yellow dye, called fluorescein, to highlight the smallest vessels in the eye so they can be photographed.

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Researchers dumped a dye, fluorescein, into the wells and monitored the marine waters along the beaches.

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This was bathed in a solution that contained molecules of fluorescein, a compound widely used as a coloring agent.

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