Microplate readers have become lab benchtop standards, a boon for researchers who require the instruments to quan-a tify chemical reactions using a range of light-detection methods. Their ability to screen entire multiwell plates in seconds affords high-throughput, parallel processing of small sample volumes. But not all microplate readers are equal, and the need for more sensitive instruments has split the market between absorbance readers and those capable of multiple-detection modes, including fluorescence and luminescence measurements.
Whereas absorbance microplate readers use visible or ultraviolet light for detection, fluorescence readers bombard samples with light that is then absorbed by fluorophores and emitted at longer wavelengths. The method, often used in cell-based studies, can offer much higher sensitivity than conventional UV-Vis absorbance detection. In addition to standard fluorescence detection, some microplate readers are designed to scan for time-resolved fluorescence and fluorescence polarization.
Luminescence readers, in contrast, detect without excitation light, relying instead on ...
