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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:
Molecular Weight:
332.31
Colour Index Number:
45350:1
Beilstein:
94324
EC Number:
MDL number:
UNSPSC Code:
12171500
PubChem Substance ID:
NACRES:
NA.47

product name

Fluorescein (free acid), Dye content 95 %

form

powder

Quality Level

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

Signal Word

Warning

Hazard Statements

Precautionary Statements

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

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Mi Ju Son et al.
Medicine, 98(29), e16527-e16527 (2019-07-25)
Several studies have found that obesity is associated with atopic dermatitis (AD); however, the mechanisms underlying the association are largely unknown. This study aims to assess the association of AD with obesity in the Korean population and verify its mechanism
Lesley-Ann Gray et al.
The Journal of infectious diseases, 216(11), 1460-1470 (2017-10-14)
Rheumatic heart disease (RHD) after group A streptococcus (GAS) infections is heritable and prevalent in Indigenous populations. Molecular mimicry between human and GAS proteins triggers proinflammatory cardiac valve-reactive T cells. Genome-wide genetic analysis was undertaken in 1263 Aboriginal Australians (398
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
Valentina Vitale et al.
Journal of equine veterinary science, 79, 9-12 (2019-08-14)
The distinction between lower respiratory tract infections caused by Rhodococcus equi and those caused by other pathogens is difficult. The aim of this retrospective study was to describe cytological findings in bronchoalveolar lavage fluid (BALF) of foals with pneumonia caused
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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