LUMINESCENCE DECAY-TIME-BASED OPTICAL SENSORS - PRINCIPLES AND PROBLEMS

Sensors based on luminescence intensity measurements suffer from the fact that, during the operating time of the instrument, changes in source intensity, light throughput, detector sensitivity, indicator quantum yield and indicator concentration are inevitable and have to be overcome by extensive referencing and recalibration procedures. Decay-time sensors should not suffer from these drawbacks. In this contribution the advantages and problems of decay-time-based sensors are reviewed and the underlying molecular mechanisms are discussed.