Our comprehensive line of reliable Microplate Readers deliver the versatility, sensitivity, precision, dynamic range and throughput you need to solve your complex analytical challenges. Every lab is unique. That's why you deserve a Microplate Reader that fits your needs. Maybe your research requires maximum application flexibility, or high throughput. Perhaps you are looking for simplicity, delivering reliable results. Whatever you need, there is a Berthold Technologies Microplate Reader to fit your research needs.
Berthold Technologies offers multimode as well as dedicated microplate readers for a wide range of detecion modes:
- Time-Resolved Fluorescence (TRF)
- Fluorescence Polarisation (FP)
Both, filter- and monochromator-based microplate readers are available. Find out more about the detection modes below:
UV/VIS Absorbance or Optical Density is used in countless classical colorimetric methods, ELISA, nucleic acid and protein quantification, and many others. The basic principle of absorbance measurements is described by Lambert-Beer's law.
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. Methods based on fluorescence offer better sensitivity, specificity and dynamic range than similar methods based on absorbance. Fluorescence is also involved in methods such as FRET and Fluorescence Polarisation (see below).
Luminescence is the result of a chemical or biochemical reaction. Thus, no excitation energy is required. Luminescence is most frequently used in methods involving reporter genes, ATP measurement and CLIA (Chemiluminescence Immunoassays). Other luminescence applicationsare caspase or kinase assays and ROS.
BRET (Bioluminescence Resonance Energy Transfer) is based on the fact that the energy derived from a luciferase reaction can be used to excite a fluorescent protein if the latter is in close proximity to the luciferase enzyme, and is thus, an excellent tool to monitor macromolecular interactions.
FRET (Fluorescence Resonance Energy Transfer) is a dual dye fluorescence detection assay. It requires a donor and an acceptor dye being in close proximity (10-100 Å). As a result of excitation, the donor fluorophore can transfer part of its energy to the acceptor fluorophore, e.g. YFP and starts emitting light without being directly excited. FRET is most frequently used to visualize molecular interactions of proteins and nucleic acids.
Fluorescence Polarisation (FP) is ideal to measure the binding of a small molecule to a much larger one. It is based on a fluorophore being excited by polarized light. Proteins and other large molecules in solution rotate slowly due to their size and emit polarized light when getting excited by polarized light. Small molecules on the other hand rotate faster and emit depolarized light. Thus, high levels of polarization indicate the presence of a larger molecule.
AlphaScreen® relies on hydrogel coated donor and acceptor beads providing functional groups for conjugation to biomolecules. When excited at 680 nm the donor bead produces singlet oxygen which transfers energy to the donor resulting in light emission between 520 and 620 nm. The amount of light produced is directly proportional to the amount of bound donor-acceptor beads. AlphaScreen® is a versatile method used to evaluate interactions between a binder (or a collection of binders) and a target (or a collection of targets).
Time-Resolved Fluorescence (TRF) uses long emission fluorophores (lanthanides) such as Europium or Terbium. These emit light over long periods of time (milliseconds) while most other fluorescent dyes emit within a few nanoseconds of being excited. Thus, TRF is similar to fluorescence intensity measurements but the timing of the excitation/detection process is different. The benefit is the elimination of background fluorescence issues from sample components such as proteins, buffers or cell lysate. TRF is used to elucidate molecular interactions, inter- or intramolecular distances, changes in the microenvironment, resolution of molecular mixtures, and more.
TR-FRET (Time-resolved fluorescence energy transfer) is a variant of FRET using long emission fluorophores (lanthanides) as donors. TR-FRET represents a powerful tool for drug discovery researchers. The resulting assay provide an increase in flexibility, reliability and sensitivity in addition to higher throughput and fewer false positive/false negative results. TR-FRET can be applied to detect the association of two molecules, for example to analyze receptor-ligand or protein-protein interactions.