Radiation-detection instrument converting ionizing beta or gamma decay from radiolabeled tracers into photomultiplier light pulses.
Specifications & Metrics
measures
Disintegrations per minute (DPM) and counts per minute (CPM) of ³H, ¹⁴C, ³⁵S, ³²P, and ¹²⁵I radioligands
Core Principles & Analysis
Following Sir Samuel Curran's invention of the first electronic scintillation counter in 1944 on the Manhattan Project, liquid scintillation counting (LSC) became the cornerstone detector for low-energy beta-emitting isotopes (tritium ³H and carbon-14 ¹⁴C) in receptor pharmacology and ADME mass-balance studies.
In liquid scintillation counting, the radioactive sample is dissolved in an aromatic organic solvent containing fluor molecules (scintillators) that absorb beta-particle kinetic energy and emit flashes of ultraviolet-visible photons detected by coincidence photomultiplier tubes.
Microplate scintillation and luminescence counters (such as MicroBeta and TopCount) arrange arrays of photomultiplier tubes or time-resolved detectors above 96- and 384-well filtermats and Scintillation Proximity Assay (SPA) plates to automate high-throughput radioligand binding.