A calibration method for handling the temporal drift of solid state gas-sensors Original Research Article

The reproducibility of chemical sensors is an issue that has to be handled in order to apply sensor-array based instruments for quality control purposes on a routine basis in the laboratory. So far, this problem can only be handled by applying mathematical algorithms to describe the temporal variation of the sensor signal. Sensor drift in a commercial solid state based sensor array device has been investigated to develop a drift compensation algorithm in order to handle the sensor drift. The calibration method uses drift compensation algorithms based on curve fitting of the temporal variation of the sensor signal of calibration samples. This procedure eliminates sensor drift within a single measurement sequence and over several sequences (days, months). It is also demonstrated that the algorithm preserves real features in the data structure of real samples that have been measured. However, this requires calibration samples that are highly correlated in sensor response with the real samples to be analysed in order to make a proper drift correction.