Solid state counting system for high energy beta and gamma decay isotopes

Abstract

The disclosure relates to a method and apparatus for quantitatively evaluating radiation emissions of radiolabeled laboratory samples. These radiation emissions frequently include high energy beta and gamma radiation emissions resulting from 32 P isotope decay. High energy beta and gamma radiation is detected by a solid state PIN photodiode and analyzed by a microprocessor to provide an indication of a radiation emission characteristic such as activity expressed in disintegrations per minute (DPM). An indication of sample activity is obtained from a detected sample count rate adjusted by a detector calibration constant which is determined by the microprocessor from a reference radiation emitting sample of known activity and volume. Indications of radiation emission characteristics may be displayed by an alpha-numeric liquid crystal display. Hard copy data may be produced from an expansion module in the form of a printer module adapted to receive data input from the microprocessor. Another expansion module, a high performance liquid chromatography (HPLC) flow detector, provides indications of radiation emissions of a sample flow passing through the flow detector. Radiation emission characteristics obtained from the sample flow may be printed by the printer module or displayed by the alpha-numeric liquid crystal display.