A sustainable and highly sensitive voltammetric method for the simultaneous determination of indigo carmine and carmoisine using a boron-doped diamond electrode.

Indigo carmine (INDG) and carmoisine (CRMS) are synthetic dyes widely used in the food industry. Their high consumption is associated with various health problems, making rigorous quality control of food products extremely important. This study describes the development and validation of a voltammetric method for the simultaneous determination of these dyes using a boron-doped diamond electrode. The linearity of the method was evaluated in the concentration range of 1.99-21.26 nmol L^-1 for INDG and 0.99-12.56 nmol L^-1 for CRMS. The determined limits of detection were 0.60 and 0.27 nmol L^-1, while the limits of quantification were 1.81 and 0.83 nmol L^-1 for INDG and CRMS, respectively. The method showed adequate selectivity, precision, and accuracy for the determination of the dyes in beverages and environmental samples. Furthermore, the high greenness score (0.74) obtained from the analysis using the Analytical GREEnness calculator demonstrated the low environmental impact of the method.