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F2456

Sigma-Aldrich

Fluorescein (free acid)

Dye content 95%, Powder

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About This Item

Empirical Formula (Hill Notation):
C20H12O5
CAS Number:
2321-07-5
Molecular Weight:
332.31
Colour Index Number:
45350:1
Beilstein:
94324
EC Number:
219-031-8
MDL number:
MFCD00005050
UNSPSC Code:
12171500
PubChem Substance ID:
24894822
NACRES:
NA.47

product name

Fluorescein (free acid), Dye content 95 %

form

powder

composition

Dye content, 95%

color

orange to red-brown

mp

320 °C (lit.)

λmax

496 nm

ε (extinction coefficient)

≥12000 at 282-286 nm
≥39000 at 236-240 nm
≥70000 at 488-492 nm

application(s)

diagnostic assay manufacturing
hematology
histology

storage temp.

room temp

SMILES string

Oc1ccc2c(Oc3cc(O)ccc3C24OC(=O)c5ccccc45)c1

InChI

1S/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

InChI key

GNBHRKFJIUUOQI-UHFFFAOYSA-N

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General description

Fluorescein (free acid, CI 45350) is a xanthene dye. Fluorescein (free acid) molecule can be divided into two parts. One part contains xanthene moiety which acts as fluorophore and the other part of the molecule bears benzene moiety which is the fluorescence-controlling moiety.

Application

Fluorescein (free acid) has been used as a staining agent in retinal imaging.
Fluorescein (free acid) is widely used as a fluorescent stain and trace for many living cells and tissue applications. It is also suitable as a marker for the study of motility of bile canaliculi. Some of the clinical applications are evaluating the ocular surface and delineation of brain regions lacking a blood-brain barrier to permit accurate surgical resection of malignant glioma. Fluorescein angiography helps investigate changes in retinal blood supply. Fluorescein also plays a role as a physiological tracer to characterize the salmon′s intestinal permeability (Schep et al., 1998), and for the fluorophotometric measurement of aqueous humor flow. It is widely employed as a quantum yield standard.

Pictograms

Exclamation mark
GHS07

Signal Word

Warning

Hazard Statements

H319

Precautionary Statements

P305 + P351 + P338

Hazard Classifications

Eye Irrit. 2

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

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J J Riesz et al.
Physical review. E, Statistical, nonlinear, and soft matter physics, 76(2 Pt 1), 021915-021915 (2007-10-13)
We report the transition dipole strength of eumelanin (the principal human photoprotective pigment) in the ultraviolet and visible. We have used both theoretical (density functional) and experimental methods to show that eumelanin is not an unusually strong absorber amongst organic
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Karen A Fisher et al.
Chemistry (Weinheim an der Bergstrasse, Germany), 9(23), 5873-5878 (2003-12-16)
The uptake of the three species of the drug model fluorescein (fluorescein sodium salt (FNa), fluorescein free acid (F), and fluorescein diacetate (FDA)) by zeolite NaX and the mesoporous zeotype MCM-41 was investigated as well as their release rates into
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