Chemometric-assisted kinetic determination of oxytetracycline using AgInS quantum dots as PL sensing platforms.

In this work a kinetic fluorometric methodology relying on the time-based monitoring of the photoluminescence quenching of AgInS ternary quantum dots induced by oxytetracycline, was developed. The kinetic approach allowed not only to reduce the LOD and improve sensitivity and selectivity but also to collect second-order data that was explored for the quantification of the target analyte in the presence of uncalibrated interfering species. Upon processing the acquired second-order kinetic PL data by unfolded partial least-squares (U-PLS), oxytetracycline was quantified in commercially available pharmaceutical formulations. The obtained results, namely an R higher than 0.99 and RE lower than 8%, proved the suitability and accuracy of the developed approach.