The Working Principle of a Fluorometer

Fluorometers are used for precise quantitation of biological molecules including nucleic acids and proteins in microliter (μl) samples. They can measure the concentration of double- and single-stranded DNA (dsDNA and ssDNA), ribonucleic acid (RNA), and proteins in solution with demonstrable applications in a range of biochemical fields. Life science, environmental monitoring, pharmaceutical quality control, and an array of bioengineering applications require fluorometers to quantify samples of interests at sub-picogram concentrations.

This blog post will explore the working principle of a fluorometer in more detail.

How Does a Fluorometer Work?

Fluorometers quantify biological analytes as a function of fluorescence. This requires the sample to be bound to a specific fluorescent agent and loaded into the instrument in a polypropylene tube. An extensive range of nucleic acid, cell function dyes, and fluorescent proteins are commercially available worldwide. However, fluorometers are typically limited to specific assay agents that are responsive to a single excitation channel such as an ultraviolet or blue beam.

Fluorophores absorb light of a distinct excitation wavelength and emit, or fluoresce, light of reduced energy thus a longer wavelength. This behavior can be modified so that the fluorescent reagents are restricted from emitting light unless bound to a specific molecule, such as dsDNA. It is, therefore, possible to directly correlate the fluorescent intensity (RFU) of the assay to the number of desirable biomolecules within the sample.

This methodology is extremely sensitive, providing biomolecular detection at sensitivities of up to 0.0005 nanograms per microliter (ng/μl). Fluorometry also delivers exclusive detection for desirable analytes, eliminating measurement inaccuracies caused by a contaminant or unknown elements in the sample. Concentrations of unknowns can then be mathematically quantified against the fluorescent intensity of known biomolecules within the assay.

Drawbacks of Conventional Fluorometry

The drawbacks of established fluorometers is a lack of assay independence. Typically, the manufacturer determines the relevant fluorescent assays by engineering fluorometers with limited excitation and emission channels.

DeNovix has eliminated this problem by designing a novel fluorometer with the modern researcher in mind. Our fluorometers are equipped with four emission and excitation channels to offer unparalleled flexibility with regards to fluorescent assay selection. These four channels cover much of the excitation (375 – 635nm) and emission (435—740nm) spectra, providing a massively expanded choice of quantification assays suitable for measuring concentration levels of dsDNA, ssDNA, RNA, and proteins in solution. Our fluorometers can also facilitate custom assays.

Fluorometers from DeNovix

DeNovix is an independent manufacturer of innovative measurement devices for research applications. We are one of the leading suppliers of fluorescence-based measuring instruments, with a unique fluorometer technology offering unequaled flexibility, sensitivity, and reproducibility for reliable fluorometric measurements.

The DS-11 FX Series of instruments combines this high dynamic range fluorometry equipment with microvolume absorbance capacities to provide best-in-class detection for biomolecules in microliter samples. You can take the DeNovix challenge and try our cutting-edge fluorometers on a free trial.

If you would like any more information about our instruments, or about trying a one-week free trial with a free dsDNA fluorometer assay, please do not hesitate to contact us.