Characterisation of Shah convolution Fourier transform detection

Multiple-point (Shah function) detected, time-domain detector signals were converted into frequency-domain plots by means of Fourier transformation. Signal-to-noise ratio enhancement by Shah convolution Fourier transform detection (SCOFF), compared with single-point detection, was obtained. Hence SCOFF could lower the detection limits and have many potential applications in trace analysis. The frequency of the fundamental peak obtained by SCOFF increases linearly with increasing migration velocity of the analyte. SCOFT is capable of extracting multiple frequency components contained in the time-domain detector signals, e.g., in a separation. Hence SCOFT could be used to interrogate a separation based on the differences in the migration velocities of the compounds in the mixture.