Fluorometer Assay
Fluorometer Assay - Related Videos
09:12
G Protein-selective GPCR Conformations Measured Using FRET Sensors in a Live Cell Suspension Fluorometer Assay
0 Views •
Cited by 4 •
2016
Simple methods to detect the selective activation of G proteins by G protein-coupled receptors remain an outstanding challenge in cell signaling. Here, Fӧrster resonance energy transfer (FRET) biosensors have been developed by pairwise tethering a GPCR to G protein peptides to probe conformational changes at controlled concentrations in live cells.
09:31
Fluorescence-based Neuraminidase Inhibition Assay to Assess the Susceptibility of Influenza Viruses to The Neuraminidase Inhibitor Class of Antivirals
0 Views •
Cited by 56 •
2017
We describe the use of a phenotypic fluorescence-based neuraminidase inhibition assay to assess the susceptibility of influenza A and B viruses to the neuraminidase inhibitor class of antivirals.
07:08
High-Density Lipoprotein-Specific Phospholipid Efflux Assay
0 Views •
2025
Herein, we describe the protocols to measure the amount of fluorescent phospholipid specifically removed from lipid donor particles by high-density lipoprotein (HDL) present in whole human plasma or serum. We have shown that this metric of HDL functionality predicts incident cardiovascular disease.
07:03
Measuring Photophysiology of Attached Stage of Colacium sp. by a Cuvette-Type Fast Repetition Rate Fluorometer
0 Views •
Cited by 1 •
2021
Fast repetition rate fluorometer (FRRf) is a beneficial method for measuring photosystem II photophysiology and primary productivity. Here we describe a protocol to measure PSII photophysiology of epizoic alga, Colacium sp. on substrate zooplankton using cuvette-type FRRf.
08:12
The TUNEL Assay
0 Views •
2023
One of the hallmarks of apoptosis is the nuclear DNA fragmentation by nucleases. These enzymes are activated by caspases, the family of proteins that execute the cell death program. TUNEL assay is a method that takes advantage of this feature to detect apoptotic cells. In this assay, an enzyme called terminal deoxynucleotidyl transferase catalyzes the addition of dUTP nucleotides to the free 3’ ends of fragmented DNA. By using dUTPs that are labeled with chemical tags that can produce...
FAQs
Excitation wavelength determines which fluorescent molecule or probe receives energy, while the instrument records emitted light at a longer wavelength. Choosing compatible settings allows the assay to monitor the intended fluorescent signal rather than an unsuitable optical response. These settings therefore connect the selected reagent or analyte to the measurement produced by the instrument.
A Fluorometer Assay can provide greater sensitivity than an absorbance-based measurement because it detects emitted fluorescence from a selected molecule or probe after excitation. This difference makes fluorescence useful when researchers need to quantify analytes at lower signal levels than an absorbance approach may reliably distinguish, provided the sample generates an appropriate fluorescent response.
Researchers measure standards containing known analyte concentrations and relate their fluorescence intensities to those values. The resulting calibration curve provides the reference for interpreting the signal from an unknown sample. Concentration is then estimated by comparing the unknown intensity with the standard response, making the measurement quantitative rather than merely signal-based.
Suitability depends on whether the analyte, fluorescent probe, or assay reagents produce a measurable fluorescent signal under the selected measurement conditions. Samples lacking an appropriate fluorescent response cannot support reliable quantification with this approach. Confirming signal compatibility is therefore an important decision before applying the assay to proteins, nucleic acids, enzymes, or molecular interaction studies.
A typical workflow begins by selecting a fluorescent molecule or probe compatible with the target measurement. The researcher then chooses excitation and emission settings, measures standards and samples with the fluorometer, and compares sample intensity with the standards or calibration curve. This sequence produces an estimated analyte concentration or another fluorescence-based biochemical readout.
In biochemistry, researchers apply this approach to protein and nucleic acid measurements, enzyme activity assays, and studies of molecular interactions. The same fluorescence readout can therefore support both concentration measurements and investigations of biochemical behavior. Its use also extends to diagnostics and drug development when the relevant sample and reagents provide a suitable fluorescent signal.