Carbon paste electrode modified Poly-Glutamic Acid (PGA) with molecularly imprinted for detection of Rhodamine B

Abstract

Rhodamine B is a synthetic dye used for coloring textiles, paper and ceramics. In addition, Rhodamine B is also often used for coloring ingredients in food ingredients such as crackers, syrups, candy, cakes, and is often used for coloring lipsticks. The accumulation of Rhodamine B in the body can cause liver, kidney and lymph damage. In this study, a modified carbon paste (EPK) electrode with molecularly imprinted polymers (glutamic acid) was developed for the determination of rhodamine B using potentiometric techniques. The modification was carried out by electro polymerization of glutamic acid monomer from a solution containing 3.0 mM glutamic acid and 1.0 mM rhodamine B in a phosphate buffer pH 7 using a cyclic voltammetry technique of 15 cycles in the potential range between -0.2 V - 1.8 V with a scan rate of 100 mV / sec. Measurements with these electrodes have optimum performance at pH 4. The Nerst factor is 29.2 mV / decade. The measurement range is 10-5 M – 10-2 M. With the detection limit of Rhodamine B which can be measured by the electrode is 8.91 × 10-6 M. This electrode has a fairly good value of accuracy and precision, and does not have a significant difference. when compared with the UV-Vis spectrophotometric method.