Silver Nanoparticles Coupled with Graphene Nanoplatelets Modified Screen-Printed Carbon Electrodes for Rhodamine B Detection in Food Products

Abstract

A rapid, simple, and sensitive voltammetric sensor has been fabricated to determine Rhodamine B (RhB), a textile coloring agent. Silver nanoparticles (AgNPs) were synthesized by the chemical reduction method of silver nitrate and sodium citrate. Graphene nanoplatelets (GPLs) and AgNPs were drop-casted on the surface of a working electrode of a screen-printed carbon electrode (SPCE), forming the SPCE-GPLs/AgNPs samples. Scanning electron microscopy−energy dispersive X-ray and cyclic voltammetry confirmed the altered surface of the SPCE. The square wave voltammetry was used for the electrochemical determination of RhB. The SPCE-GPLs/AgNPs demonstrated electrochemical responses to detect RhB with a linear range of 2−100 μM, and the limit of detection was 1.94 μM. The SPCE-GPLs/ AgNPs demonstrated a selective detection of RhB in the presence of common interfering compounds present in the food samples, including sucrose and monosodium glutamate. Furthermore, the sensor presented good reproducibility as well as repeatability in the detection of RhB. When the sensor was used to determine RhB in an actual food sample, similar results were shown as suggested by UV−vis spectroscopy analysis. Hence, the fabricated sensor can be applied for the detection of RhB in food samples.

Voltammetric Behaviour of Rhodamine B at a Screen-Printed Carbon Electrode and Its Trace Determination in Environmental Water Samples

“…Table 1 provides a comparison of the optimised DPV method with previously reported analytical methods for the determination of Rhodamine B. The linear range for the method is comparable to that reported by high performance liquid chromatography following solid phase extraction [17] and that recorded for modified SPCEs [29]. The quoted limit of detections for the spectroscopy-based approaches [67,70,73] are lower than those for the voltammetric method developed here, however, these necessitate time-consuming, complex sample pre-treatment steps.…”

“…The results shown in Table 2 indicate that the method gives reliable results using an external calibration method. The analytical performance characteristics were better than those reported at a glassy carbon electrode [28] and an Ag nanoparticle modified screen-printed electrode [29]. It was also shown possible to determine Rhodamine B via cyclic voltammetry using the same SPCE over the range 0.50-1025 µgmL −1 (R 2 = 0.9929).…”

“…Rhodamine B has been studied at a number of different electrode materials [28][29][30][31][32][33][34][35]. However, it is believed that this study represents the first report on the voltammetric behaviour and determination of Rhodamine B in an environmental water sample at an unmodified SPCE.…”

Highly selective electrochemical sensing based on electropolymerized ion imprinted polyaniline (IIPANI) on a bismuth modified carbon paste electrode (CPE-Bi) for monitoring Nickel(ii) in river water

“…As an alternative, a carbon-based electrode is generally used. [14][15][16][17] It is imperative to note that a bare electrode, such as carbon, platina, or gold electrode, usually exhibits a relative low electrochemical response to an analyte. Therefore, the modulation of the electronic structure on the electrode surface is required to improve the current response.…”

“…Therefore, the modulation of the electronic structure on the electrode surface is required to improve the current response. 14,[18][19][20][21][22][23]55 Studies have shown that a bismuth-modied carbon paste electrode exhibits excellent performance in tracking heavy metal ions at a low concentration, as suggested by a greater current response in comparison to a bare carbon paste electrode. 18,20,21 A polymer containing an ion template and a functional monomer is called as an ion-imprinted polymer (IIP).…”