Fluorescence Intensity (including FRET)

Fluorescence intensity-based detection can be performed on the PHERAstar® FSX, CLARIOstar®, and FLUOstar® and POLARstar® Omega plate readers. A high-intensity xenon flashlamp in all BMG microplate readers provides high performance measurements, while assay-specific filters, optic modules, or LVF monochromators™ select the specific wavelengths, yield higher light transmission, and minimize unwanted background noise. Low-noise or extended red-shifted PMTs provide, combined with a user-adjustable gain, a measurement window of more than 6 logs intensity.

Fluorescence microplate reader

Fluorescence Overview

Fluorescence intensity detection is the measurement of the light emitted by a fluorescent molecule (fluorophore) upon excitation by light at a higher energy and smaller wavelength. A sample is excited by the light produced by a light source and filtered at a specific wavelength by either a filter or a monochromator. The excited sample emits light usually at a lower energy and longer wavelength than the excitation light and fluoresces within µseconds upon excitation. The emitted light is filtered, collected, and measured by a detector, usually a Photo Multiplier Tube (PMT), and quantified in Relative Fluorescence Units (RFU). The vast development of countless fluorophores over the last two decades has made fluorescence intensity one of the most popular detection modes for microplate readers, with thousands of assays available for many different applications.

FRET is a dual dye fluorescence detection assay based upon Fluorescence Resonance Energy Transfer between a donor and an acceptor. If donor and acceptor are in close proximity (10-100 Å), excitation of the donor fluorophore transfers energy to the acceptor fluorophore that will emit light without being directly excited. FRET is mainly used to monitor interactions between molecules.

Fluorescence Intensity Products

The following plate readers can be configured to perform fluorescence measurements:
PHERAstar FSX HTS plate reader CLARIOstar multi-mode plate reader Omega Series upgradeable plate readers
The new High-Throughput
Screening reader for fast
read times in all modes.
An advanced monochromator
reader for flexibility and
performance in all modes.
Upgradeable Omega Series
readers for fluorescence or any
number of detection modes.

Fluorescence Intensity/FRET Measurements

The following are examples of fluorescence intensity and FRET measurements taken on BMG LABTECH microplate readers:

See a complete list of fluorescence intensity application notes.