A Novel Pvc-Membrane Potentiometric Sensor Based on Molecularly Imprinted Polymer for the Determination of Rhodamine B

Abstract

A rhodamine B (RH-B)-imprinted functional polymer was synthesized by free radical polymerization, utilizing RH-B as the template, methacrylic acid as the functional monomer, and ethyleneglycol dimethylacrylate as the cross-linker. The synthesized RH-B-imprinted polymer was characterized by FT-IR measurements. A novel RH-B-selective potentiometric poly(vinyl chloride) (PVC) membrane sensor was fabricated using this newly synthesized RH-B-imprinted functional polymer as the ionophore. Membrane optimization studies revealed that the most satisfactory membrane composition, yielding the best potentiometric parameters, comprised 32.0% (w/w) PVC, 64.0% (w/w) dibutyl phthalate, 3.0% (w/w) RH-B-imprinted polymer, and 1.0% (w/w) potassium tetrakis(4-chlorophenyl)borate. Further investigations into the potentiometric performance characteristics of the optimum composition demonstrated that the sensor exhibited a linear response to RH-B within the concentration range of 1.0 x 10-7 to 1.0 x 10-2 M with a detection limit of 1.0 x 10-8 M and a near Nernstian slope of 67.37 mV/decade. The sensor's analytical proficiency was evidenced by its precise quantification of RH-B in RH-B-spiked rose-water samples, resulting in satisfactory recovery rates.