Based on the Random House Dictionary, © Random House, Inc. 2012.
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| the molecular weight of a substance expressed in grams; a gram molecule |
| a double sulfate analogous to potassium alum, as aluminum ammonium sulfate, with the formula R2SO4?X2(SO4)3?24H2O, where R is alkali metal or ammonium |
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fluorescein fluo·res·ce·in (fl&oobreve;-rěs'ē-ĭn, flô-)
n.
An orange-red compound that exhibits intense fluorescence in alkaline solution and is used in ophthalmology to reveal corneal lesions.
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fluorescein  (fl -rěs'ē-ĭn, flô-) Pronunciation Key
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: C20H12O5. |
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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fluorescein
organicorganic compound of molecular formula C20H12O5 that has wide use as a synthetic colouring agent. It is prepared by heating phthalic anhydride and resorcinol over a zinc catalyst, and it crystallizes as a deep red powder with a melting point in the range of 314 to 316 C (597 to 601 F). Fluorescein was named for the intense green fluorescence it imparts to alkaline solutions-a colour visible even at dilutions of 1:50,000,000. It is used as a dye to colour liquids in analytic instruments, in cosmetics, and as a water tracer or marker. Halogenated derivatives made from fluorescein also include eosin and erythrosin.
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