Enhanced electrochemical detection of tartrazine in beverages and liquid soap via nickel phosphide-adorned functionalized carbon nanofibers

Background Tartrazine (TAT) is a widely used food colorant dye, offering an orange-yellow hue in various products such as foods, cosmetics, and pharmaceuticals. Despite its popularity, TAT is banned in several countries due to its potential health risks, including respiratory issues, migraines, and skin allergies. Moreover, TAT is linked with adverse effects on human physiology, including mutagenicity, biliary cirrhosis, changes in liver and kidney functions, and neurodegeneration at varying doses. Consequently, the detection of this food additive is crucial for safeguarding human health and protecting aquatic organisms. Methods In this study, a novel sensor was developed for the detection of TAT, utilizing a composite material made from nickel phosphide decorated with functionalized carbon nanofiber (Ni2P@f-CNF). The Ni2P@f-CNF was synthesized and characterized through several techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, field emission-scanning electron microscopy, and elemental mapping. The composite was then integrated with a glassy carbon electrode to create a sensor. The sensor's performance was evaluated in terms of detection limit, linear range, selectivity, sensitivity, reproducibility, repeatability, and long-term stability. Main Findings The developed Ni2P@f-CNF composite sensor displayed a lower detection limit of 0.011 µM and a broad linear range from 0.01 to 1875 µM. Its selectivity and sensitivity were exceptional, primarily due to the catalytic activity of the Ni2P@f-CNF composite towards TAT. The sensor also demonstrated excellent reproducibility, repeatability, and notable long-term stability. Importantly, when applied in real-world scenarios, the sensor successfully detected TAT in soft drink and liquid soap samples, yielding high recovery rates between 97.45 % to 99.37 % and 98.26 % to 99.01 %, respectively, underscoring its potential applicability in practical settings.