WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 581069

CAS#: 76823-03-5

Description: 5-Carboxyfluorescein is a highly soluble dye which is utilized as a pH indicator. 5-Carboxyfluorescein displays strong fluorescence and is concentration dependent. This compound labels proteins, nucleotides and peptides from carboxylic acid interacting with primary amines.

Chemical Structure

CAS# 76823-03-5

Theoretical Analysis

MedKoo Cat#: 581069
Name: 5-FAM
CAS#: 76823-03-5
Chemical Formula: C21H12O7
Exact Mass: 376.0583
Molecular Weight: 376.32
Elemental Analysis: C, 67.03; H, 3.21; O, 29.76

Price and Availability

Size Price Availability Quantity
50.0mg USD 180.0 2 Weeks
100.0mg USD 300.0 2 Weeks
1.0g USD 620.0 2 Weeks
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Synonym: 5-FAM; 5-Carboxyfluorescein; 5 FAM; 5FAM; 5 Carboxyfluorescein; 5Carboxyfluorescein;

IUPAC/Chemical Name: 5-Carboxyfluorescein; 3',6'-Dihydroxy-3-oxo-spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-5-carboxylic acid


InChi Code: InChI=1S/C21H12O7/c22-11-2-5-15-17(8-11)27-18-9-12(23)3-6-16(18)21(15)14-4-1-10(19(24)25)7-13(14)20(26)28-21/h1-9,22-23H,(H,24,25)

SMILES Code: O=C1OC2(C3=C(OC4=C2C=CC(O)=C4)C=C(O)C=C3)C5=C1C=C(C(O)=O)C=C5

Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 376.32 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Weinstein JN, Blumenthal R, Klausner RD. Carboxyfluorescein leakage assay for lipoprotein-liposome interaction. Methods Enzymol. 1986;128:657-68. PubMed PMID: 3724529.

2: David R, Machova Z, Beck-Sickinger AG. Semisynthesis and application of carboxyfluorescein-labelled biologically active human interleukin-8. Biol Chem. 2003 Dec;384(12):1619-30. PubMed PMID: 14719805.

3: Fischer R, Mader O, Jung G, Brock R. Extending the applicability of carboxyfluorescein in solid-phase synthesis. Bioconjug Chem. 2003 May-Jun;14(3):653-60. PubMed PMID: 12757391.


50.0mg / USD 180.0