Multiplex detection of antidepressants with a single component condition-based colorimetric sensor array

Pattern-based sensing with multi-component sensor arrays, despite its merits, may be laborious and time-consuming. As an alternative approach, herein, a condition-based single component sensor array has been provided which represents an elegantly simple, low cost and minimally instrumented format for the quantification and classification of antidepressants (ADs). Tuning the pH and ionic strength enabled the single component probe to interact with the target analytes through different binding modes, providing the required cross-reactivity for multiplex detection. The analytical figures of merit verified that the condition-based sensor array is precise and accurate in both the discrimination and quantification of the ADs. Excellent sensitivity and selectivity were achieved in the discrimination of the ADs. Moreover, low limit of detections (as low as 0.009 μg.mL−1) and wide linear ranges (up to four orders of magnitude) were attained in the multivariate calibration of each AD. The results of multivariate calibration (R2cal>0.99 and R2cv>0.99) and classification (sensitivity 100% and specificity 100%) of ADs in human urine ensured the practicability of the array in complex biological fluids. Furthermore, the wide-ranging colorimetric responses that appeared due to the different environment sensitive aggregation patterns allowed visual detection.