Red-Emissive Ruthenium-Phenanthroline Probe-Based Spectrofluorimetric Determination of Fast Green FCF in Beverages...

The widespread incorporation of synthetic dyes in food products has raised increasing analytical and regulatory concerns due to their potential health risks. Fast Green FCF (FT-G; E143), a widely used triarylmethane dye, is frequently added to various food products. Despite its strong chemical stability and low production cost, FT-G has been associated with several toxicological effects. This study introduces a rapid, cost-effective, and sensitive analytical strategy for the determination of FT-G. The proposed work combines liquid-liquid salting-out extraction (LL-SO-E) as an efficient extraction step with spectrofluorimetric detection based on fluorescence quenching of a prepared ruthenium-phenanthroline complex by FT-G. The experimental parameters affecting both the extraction and fluorescence detection processes were systematically optimized. Under the optimized conditions, the method exhibited good linearity over the concentration range of 0.2-2.0 μg mL^-1, with a LOD of 0.065 μg mL^-1 and a LOQ of 0.196 μg mL^-1. Furthermore, spectrofluorimetric measurements were performed at an excitation wavelength of 469 nm and an emission wavelength of 613 nm. The applicability of the proposed method was demonstrated by the determination of FT-G in spiked beverage matrices with acceptable recoveries.