ANALYSIS OF THE BASELINE DRIFT ARTIFACT IN HADAMARD TRANSFORM SEPARATION TECHNIQUES

The baseline drift artifact (BDA), namely, the baseline bias between the Hadamard transform (HT) spectrum and the signal averaging (SA) spectrum was unfortunately found in the HT pulsed separation techniques, which makes the HT analytical chemistry face the challenge of non-stability and unreliability. In order to find out the origin and eliminate the BDA phenomenon, the multiplexing mechanism of Hadamard transform ion mobility spectrometry (HT-IMS) has been analyzed in this research. Through simulation and experimental comparisons, the non-ideal overlap defect in Hadamard multiplexing process was suggested as the cause for the BDA phenomenon. Eventually, with a correction method, the BDA phenomenon could be well addressed, which guarantees the reliability and stability of HT techniques without increasing the hardware complexity.