(3-(2-Furoyl)-quinoline-2 carboxaldehyde)

{{Short description|Fluorogenic amine labelling dye}}

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| Name = FQ

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| ImageFile = (3-(2-furoyl)-quinoline-2 carboxaldehyde) chemical structure.svg

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| IUPACName = 3-(furan-2-carbonyl)quinoline-2-carbaldehyde

| OtherNames = FQ, (3-(2-furoyl)-quinoline-2 carboxaldehyde), ATTO-TAG FQ, FQCA

| Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| CASNo = 126769-01-5

| ChemSpiderID = 110807

| EC_number = 635-028-8

| PubChem = 124404

| SMILES = C1=CC=C2C(=C1)C=C(C(=N2)C=O)C(=O)C3=CC=CO3

| InChI = 1S/C15H9NO3/c17-9-13-11(15(18)14-6-3-7-19-14)8-10-4-1-2-5-12(10)16-13/h1-9H

| InChIKey = PNCHURHVMDRFTR-UHFFFAOYSA-N

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|Section2={{Chembox Properties

| C=15 | H=9 | N=1 | O=3

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|Section3={{Chembox Hazards

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3-(2-Furoyl)-quinoline-2-carboxaldehyde (FQ) is a fluorogenic amine labeling dye that is not fluorescent itself, but reacts with primary amines to form fluorescent products.{{Cite journal |last1=Stoyanov |first1=Alexander V. |last2=Ahmadzadeh |first2=Hossein |last3=Krylov |first3=Sergey N. |date=2002-11-25 |title=Heterogeneity of protein labeling with a fluorogenic reagent, 3-(2-furoyl)quinoline-2-carboxaldehyde |url=https://pubmed.ncbi.nlm.nih.gov/12401353/ |journal=Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences |volume=780 |issue=2 |pages=283–287 |doi=10.1016/s1570-0232(02)00535-4 |issn=1570-0232 |pmid=12401353}} It was first reported in 1990.{{cite journal | last1=Beale | first1=Stephen C. | last2=Hsieh | first2=You-Zung | last3=Wiesler | first3=Donald | last4=Novotny | first4=Milos | title=Application of 3-(2-furoyl)quinoline-2-carbaldehyde as a fluorogenic reagent for the analysis of primary amines by liquid chromatography with laser-induced fluorescence detection | journal=Journal of Chromatography A | publisher=Elsevier BV | volume=499 | year=1990 | issn=0021-9673 | doi=10.1016/s0021-9673(00)97002-x | pages=579–587| pmid=2324216 }} Cyanide, typically provided via KCN or NaCN salts, is a required co-substrate in the fluorogenic reaction.{{cite web |title=ATTO-TAG CBQCA and ATTO-TAG FQ - Product Information|first1=Thermo |last1=Fisher Scientific |url=https://assets.thermofisher.com/TFS-Assets%2FLSG%2Fmanuals%2Fmp02333.pdf |publisher=Thermo Fisher Scientific |access-date=8 April 2023}} It has been used for the detection of amines and peptides, largely in CE-SDS, where it is recognized to reach a silver stain-like high sensitivity via laser-induced fluorescence.{{cite journal | last1=Arrell | first1=Miriam S. | last2=Kálmán | first2=Franka | title=Estimation of protein concentration at high sensitivity using SDS-capillary gel electrophoresis-laser induced fluorescence detection with 3-(2-furoyl)quinoline-2-carboxaldehyde protein labeling | journal=Electrophoresis | publisher=Wiley | volume=37 | issue=22 | date=2016-10-19 | issn=0173-0835 | doi=10.1002/elps.201600246 | pages=2913–2921| pmid=27570211 | s2cid=11359248 }} Once bound to protein the excitation wavelength is 480 nm (blue) and the emission wavelength is ~600 nm (orange).{{cite web | title=3-(2-Furoyl)quinoline-2-carboxaldehyde | website=sigmaaldrich.com | url=https://www.sigmaaldrich.com/US/en/product/sigma/17884 | access-date=2023-03-09}}