Automatic potentiometric system for quantification of three imidazole derivatives based on new polymeric PVC membrane sensors

摘要

New potentiometric monitoring devices for trace and fast determination of three imidazole derivatives were presented. The sensing materials were fabricated by the inclusion of imidazolinium phosphomolybdate (Imd/PMA) (sensor I), imidazolinium tetraphenylborate (Imd/TPB) (sensor II), or dibenzo-24-crown-8 (DB24C8) (sensor III) in the plasticized polyvinyl chloride (PVC) matrix. The sensors showed clear enhanced response towards imidazolium [Imd(+)] ions over the concentration range 4.0 x 10(-6)-1 x 10(-2) mol L-1 at pH 5 with 0.42 mu g mL(-1) as a detection limit. The selectivity was tested with various inorganic and nitrogenous organic ions. Long life span, fast response, long-term stability, and high reproducibility are shown for the sensors. Method validation for the proposed method was achieved by quantifying the detection limit, linear range, accuracy, precision, repeatability, and between-day variability. It revealed good performance characteristics of the proposed sensors. The applicability of the sensors for analyzing imidazole in urine samples was successfully demonstrated via recovery studies.