Electroanalytical Performance of (SiPy+Cl−/CuTsPc)5 LbL Film for Detecting Promethazine Hydrochloride

A (SiPy+Cl−/CuTsPc)5 layer‐by‐layer film was employed for the electroanalytical determination of promethazine hydrochloride in BR buffer pH 5.0 with peaks at 0.48 and 0.79 V. After optimisation of the square‐wave parameters (f=100 s−1, a=40 mV and ΔEs=2 mV), the peak at 0.79 V was used for quantification and a detection limit of 8.71×10−9 mol L−1 and a quantification limit of 9.31×10−8 were calculated. The applicability of this procedure was tested on commercial formulations of promethazine hydrochloride by observing the stability, specificity, recovery and precision of the procedure in complex samples, without any preliminary treatment.