PubChem Notes:

Fluorescein A phthalic indicator dye that appears yellow-green in normal tear film and bright green in a more alkaline medium, such as the aqueous humor, and is used therapeutically as a diagnostic aid in corneal injuries and corneal trauma. It has been approved by FDA for use in externally applied drugs and cosmetics. (From Merck Index, 12th ed; American Medical Association Drug Evaluations; 1995, p2275)

MediLexicon fluorescein - Medical Dictionary Definition for Term 'fluorescein'

[1. An orange-red crystalline powder that yields a bright green fluorescence in solution and is reduced to fluorescin; a nontoxic, water-soluble indicator used diagnostically to trace water flow.

Molecular Formula: C20H12O5

InChI: InChI=1/C20H12O5/c21-11-5-7-15-17(9-11)24-18-10-12(22)6-8-16(18)20(15)14-4-2-1-3-13(14)19(23)25-20/h1-10,21-22H

SMILES: C1=CC=C2C(=C1)C(=O)OC23C4=C(C=C(C=C4)O)OC5=C3C=CC(=C5)O

    Fluorescein,CI 45350

    PubChem CID 16850
    PubChem ID 10472079