Adsorptive Stripping Voltammetric Determination of Amaranth and Tartrazine in Drinks and Gelatins Using a Screen-Printed Carbon Electrode

Abstract

A fast, sensitive, and selective method for the simultaneous determination of one pair of synthetic colorants commonly found mixed in food products, Amaranth (AM) and Tartrazine (TZ), based on their adsorption and oxidation on a screen-printed electrode (SPE) is presented. The variation of peak current with pH, supporting electrolyte, adsorption time, and adsorption potential were optimized using square wave adsorptive voltammetry. The optimal conditions were found to be: pH 3.2 (PBS), Eads 0.00 V, and tads 30 s. Under these conditions, the AM and TZ signals were observed at 0.56 and 0.74 V, respectively. A linear response were found over the 0.15 to 1.20 µmol L−1 and 0.15 to 0.80 µmol L−1 concentrations, with detection limits (3σ/slope) of 26 and 70 nmol L−1 for AM and TZ, respectively. Reproducibility for 17.7 µmol L–1 AM and TZ solutions were 2.5 and 3.0% (n = 7), respectively, using three different electrodes. The method was validated by determining AM and TZ in spiked tap water and unflavored gelatin spiked with AM and TZ. Because a beverage containing both AM and TZ was not found, the method was applied to the determination of AM in a kola soft drink and TZ in an orange jelly and a soft drink powder.

Size of Heparin-Imprinted Nanoparticles Reflects the Matched Interactions with the Target Molecule

“…MIPs have comparable affinity and specificity to antibodies, but they are more robust and can be prepared more economically and rapidly than antibodies. MIPs are also feasible as molecular recognition elements in biosensors [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. Most of the applications of MIPs for sensors are based on the direct detection of the mass of the template bound with the MIPs (e.g., detection of the mass of the template by a quartz crystal microbalance (QCM) [2,3], detection of change in the refractive index by surface plasmon spectroscopy [4,5], or detection of the electrochemical template by stripping voltammetry [6,7]), detection by change in impedance [8], detection of the ionic template by potentiometry [9], or detection of the optical properties of the template [10].…”

Surface Plasmon Resonance Based Sensor for Amaranth Detection With Molecularly Imprinted Nanoparticles

“…Tartrazine, amaranth, sunset yellow, carmoisine, and allura red are some of the most used azo dyes in the food industry. Amaranth is a reddish dye used to color various foodstuffs and cosmetics [4][5][6]. Amaranth has been shown to be toxic to human lymphocytes in vitro.…”

Electrochemical determination of amaranth in food samples using activated carbon-Co3O4 modified electrode

“…For example, in both the USA and Japan, the use of amaranth has been voluntarily restricted in foodstuffs and beverages [7] and in China, amaranth is permitted to be added into some foodstuffs [8]. The World Health Organization has set the acceptable daily intake of amaranth as 0.5 mg kg -1 [9]. Therefore, the content of amaranth in foods must be severely controlled and the detection of amaranth in a rapid, sensitive, simple, and cost-effective manner is paramount for human health and food safety.…”