Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays

A Black Hole Quencher-3 (BHQ-3) derivative was synthesized through an azo-coupling reaction between Methylene Violet 3RAX and a tertiary aniline functionalized with a pendant primary amine, allowing subsequent peptide conjugation. The synthesized compounds were characterized using NMR, UV–vis absorp...

Full description

Saved in:
Bibliographic Details
Main Authors: Cátia D. F. Martins, Maria Manuela M. Raposo, Susana P. G. Costa
Format: Article
Language:English
Published: MDPI AG 2024-11-01
Series:Chemistry Proceedings
Subjects:
Online Access:https://www.mdpi.com/2673-4583/16/1/48
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850156734413275136
author Cátia D. F. Martins
Maria Manuela M. Raposo
Susana P. G. Costa
author_facet Cátia D. F. Martins
Maria Manuela M. Raposo
Susana P. G. Costa
author_sort Cátia D. F. Martins
collection DOAJ
description A Black Hole Quencher-3 (BHQ-3) derivative was synthesized through an azo-coupling reaction between Methylene Violet 3RAX and a tertiary aniline functionalized with a pendant primary amine, allowing subsequent peptide conjugation. The synthesized compounds were characterized using NMR, UV–vis absorption, fluorescence spectroscopy, and mass spectrometry. The spectral properties of a Cy5/BHQ-3 amine pair were investigated through titration experiments in PBS (pH 7.4). The results confirmed Förster Resonance Energy Transfer (FRET), along with additional dynamic quenching, as evidenced by the Stern–Volmer analysis. The Stern–Volmer constant (<i>K<sub>SV</sub></i>) was determined to be 1.40 × 10<sup>5</sup> M<sup>−1</sup>. These findings confirm the potential of this system for use in molecular probes and bioimaging applications.
format Article
id doaj-art-4eea43ee6102493da8dd5d7b7390e97e
institution OA Journals
issn 2673-4583
language English
publishDate 2024-11-01
publisher MDPI AG
record_format Article
series Chemistry Proceedings
spelling doaj-art-4eea43ee6102493da8dd5d7b7390e97e2025-08-20T02:24:25ZengMDPI AGChemistry Proceedings2673-45832024-11-011614810.3390/ecsoc-28-20170Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity AssaysCátia D. F. Martins0Maria Manuela M. Raposo1Susana P. G. Costa2Centre of Chemistry, University of Minho, Campus de Gualtar, 4710-057 Braga, PortugalCentre of Chemistry, University of Minho, Campus de Gualtar, 4710-057 Braga, PortugalCentre of Chemistry, University of Minho, Campus de Gualtar, 4710-057 Braga, PortugalA Black Hole Quencher-3 (BHQ-3) derivative was synthesized through an azo-coupling reaction between Methylene Violet 3RAX and a tertiary aniline functionalized with a pendant primary amine, allowing subsequent peptide conjugation. The synthesized compounds were characterized using NMR, UV–vis absorption, fluorescence spectroscopy, and mass spectrometry. The spectral properties of a Cy5/BHQ-3 amine pair were investigated through titration experiments in PBS (pH 7.4). The results confirmed Förster Resonance Energy Transfer (FRET), along with additional dynamic quenching, as evidenced by the Stern–Volmer analysis. The Stern–Volmer constant (<i>K<sub>SV</sub></i>) was determined to be 1.40 × 10<sup>5</sup> M<sup>−1</sup>. These findings confirm the potential of this system for use in molecular probes and bioimaging applications.https://www.mdpi.com/2673-4583/16/1/48azo dyesBHQ-3FRETproteasesquenching
spellingShingle Cátia D. F. Martins
Maria Manuela M. Raposo
Susana P. G. Costa
Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
Chemistry Proceedings
azo dyes
BHQ-3
FRET
proteases
quenching
title Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
title_full Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
title_fullStr Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
title_full_unstemmed Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
title_short Straightforward Synthesis of BHQ-3 Amine: An Azo Dark-Quencher for FRET-Based Protease Activity Assays
title_sort straightforward synthesis of bhq 3 amine an azo dark quencher for fret based protease activity assays
topic azo dyes
BHQ-3
FRET
proteases
quenching
url https://www.mdpi.com/2673-4583/16/1/48
work_keys_str_mv AT catiadfmartins straightforwardsynthesisofbhq3amineanazodarkquencherforfretbasedproteaseactivityassays
AT mariamanuelamraposo straightforwardsynthesisofbhq3amineanazodarkquencherforfretbasedproteaseactivityassays
AT susanapgcosta straightforwardsynthesisofbhq3amineanazodarkquencherforfretbasedproteaseactivityassays