Applications of ionizing radiation to detection in liquid chromatography

Beta-induced fluorescence (BIF) is the luminescence excited from a compound as a result of the passage of beta-particle radiation through a compound or dilute solution of a compound. A liquid chromatographic detector, based on the principle of BIF, has been developed which allowed the detection and quantitation of fluorescent materials. A number of flow cells, incorporating ,a promethium-147 beta particle emitter, were designed and developed with the objective of attaining maximum sensitivity from the detection technique. The response of, the detector to eluted materials, the linearity of the detector response with sample loading and the sensitivity of the detector were examined in normal and reversed phase liquid chromatography. During the development of the BIF detector it became evident that the compounds detected need not be inherently fluorescent. The range of compounds detected could be increased to include those which quench the beta-induced fluorescent emission from the mobile phase. The technique of quenched beta-induced fluorescence was investigated as a detection technique and the response, linearity of response and sensitivity to eluted materials examined. Cerenkov photons are generated whenever a charged particle, travelling at a velocity greater than the velocity of light in the medium, passes through a transparent medium. Cerenkov photons are emitted from the medium as a continuum of wavelength range between 180 nm and 600 nm. The principle of absorption of Cerenkov photons was investigated as a detection technique in liquid chromatography. Strontium-90 was incorporated into a number of flow cells and the response, linearity of response and sensitivity of eluted materials, examined in normal and reversed phase liquid chromatography.