  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
electrode (CPE) with molecularly imprinted polymers (glutamic acid) was
developed for the determination of rhodamine B using potentiometric techniques.
The modification was carried out by electropolymerization 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) to (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 to 10-2 M. With the
detection limit of Rhodamine B which can be measured by the electrode is 8.91 x
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.
