BHQ-2 amine | CAS 1241962-11-7

BHQ-2 amine is a fluorescence quencher building block designed for conjugation to biomolecules and assay components. As an amine-functionalized quencher, it is commonly used to suppress fluorescence from nearby fluorophores in FRET-style designs and nucleic-acid-based signal control formats, where distance-dependent quenching helps reduce background and enable target-dependent fluorescence readouts. In fluorescence workflows, BHQ-2 amine is particularly valued as a reactive quencher handle for constructing quencher-fluorophore pairs and immobilized probe systems.

1. FRET Quencher Pairing

BHQ-2 amine is used to construct FRET quencher-donor pairs for fluorescence-based biosensor and assay development, including proximity- and distance-controlled signal designs. Researchers and assay developers incorporate the amine-functional quencher into donor-quencher conjugates or labeled recognition reagents so that fluorescence from the donor is efficiently suppressed when the quencher is positioned close to the emitting dye. This format is widely used in homogeneous fluorescence workflows where signal modulation is driven by structural rearrangement, binding-induced proximity changes, or engineered distance changes between the fluorophore and quencher.

2. Oligonucleotide Probe Quenching

BHQ-2 amine supports quenched fluorescence oligonucleotide probe construction for nucleic acid analysis workflows, including hybridization- and separation-based readouts. In these designs, the amine handle enables straightforward conjugation of the quencher to modified nucleic acids or to probe scaffolds used in molecular biology assays, where quencher placement allows suppression of fluorophore emission in the unbound state. Upon target-dependent structural changes (for example, hybridization or probe assembly), fluorescence recovery provides a readout compatible with plate readers, fluorescence scanners, and common nucleic-acid analysis instrumentation.

3. Molecular Beacon Signal Control

BHQ-2 amine is applied in molecular beacon-style probe systems where quencher-fluorophore proximity governs the on/off fluorescence response. Probe developers use the amine-functional quencher to prepare beacon constructs that maintain low background signal until target binding promotes a conformational change that separates the fluorophore from the quencher. This approach is used in fluorescence monitoring workflows for nucleic acid detection and real-time signal reporting in research settings, including experiments that require robust suppression of free-dye background and clear fluorescence recovery upon target engagement.

4. Surface Immobilized Quenching

BHQ-2 amine is also used to create surface- or material-associated quenching elements for fluorescence imaging and analytical reagent development. By leveraging the amine functionality, researchers can immobilize BHQ-2 onto activated surfaces, polymer matrices, or scaffolded materials that are later combined with fluorescent labels in proximity-based designs. Such immobilized quenching architectures are used to control background fluorescence in patterned assay formats, microarray-like platforms, and material-based fluorescence readouts where spatially defined quenching improves interpretability of fluorescence signals.