Luminometer has been in the laboratories for over a decade, helping the scientists to easily intercept results and to get ready-to-analyze results for their molecular queries. This technology has been proving consistent and reliable when it comes to water analysis.
Luminometer is a device that measures the intensity of light or the optical properties of the sample. It is a variation of the typical photometer to measure the illumination of the samples. Luminometer can be used to detect the luminance in the wide variety of assays including ATP assays, luciferase assays, for drug conjugation and discovery, gene reporter assays, etc.
A Luminometer is very essential for interpretation of experimental results and analysis. Some instruments will scan UV and fluorescence in addition to measuring light intensity. When you are looking for purchasing a Luminometer, check for the dynamic range and sensitivity of the instrument. Also, keep in mind to check the cross talks and background interferences, which should actually be not there in ideal cases and the least in general.
Assays with Luminometer:
Generally, Luminometer is widely used to measure the Adenosine Triphosphate – ATP molecule, which is considered as a chemical marker for most of the assays. ATP is found in all types of living cells. The total levels of ATP are used to measure cell viability, proliferation, and other wide range of compound and bio-modification responses.
How does the Luminometer work?
Some biological organisms produce light reactions with the help of Luciferin and luciferases, while the others produce light through the reactions with ATP. Based on the reaction of ATP with the luciferase enzyme, there is a glow and the amount of ATP is a direct measure of the intensity of light (RLU). The light produced by these reactions also called as bioluminescence could be scaled by a Luminometer. The amount of light that is produced is a direct measure of the number of ATPs present. The amount of ATP, in turn, provides a direct measurement of biological concentration and health.
Parts of Luminometer:
A Luminometer consists of a detector or a Photon Multiplier Tube (PMT) and a light-tight chamber. The Light-tight chamber is used to read the signals produced during a luminescent reaction while the PMT detects the number of photons. There are two types of PMTs being used, a current mode and a photon counting mode. The photon counting PMTs are widely accepted and reduces the work of a scientist in doing an experiment. Additional parts like liquid handling systems, filters, and automated settings are bonus considerations.
Types of Luminometer:
There are various types of Luminometer that are used for various assays. Tube Luminometer can read simple tubes and we need to measure the individual sample (tube). Though it has high sensitivity and leaves a small footprint, it increases the mechanical works of the scientist. Microplate Luminometer can do a sequential measurement of the samples placed in the microtitre plates consisting of 96 to 320 wells. These are very fast and can be used conveniently. Recent day equipment comes with automated sample injections and this option reduces the mechanical work of scientist and also is robust and reproducible. However, these are not as sensitive as the tube Luminometer and are costly. But most of the present gen labs use microplate Luminometer.
While purchasing a Luminometer, a scientist must make sure that the instrument makes the job easier rather than the other way around. Optical features, low dead volume, user-friendliness, software compatibility are also a few other things to check during the purchase.