Green and Sustainable Spectrofluorometric Determination of Nitrofurantoin in Pure Form and Water Samples Using Functionalized Carbon Quantum Dots.

The environmental impact of chemicals used in aquaculture, particularly nitrofurantoin, has raised global concern. Nitrofurantoin, a broad-spectrum antimicrobial, is commonly used in aquaculture despite safety risks. Determination of nitrofurantoin in water samples of fish ponds is necessary to ensure the safety and quality of seafood. Herein, a new spectrofluorometric method was created for the determination of nitrofurantoin in water samples from fish ponds. Carbon quantum dots were functionalized with nitrofurantoin tetra phenyl borate modifying their surface to be selective for nitrofurantoin quantification. When nitrofurantoin is present, the functionalized carbon quantum dots show concentration-dependent fluorescence quenching, allowing estimation of the drug. The method was validated and demonstrated accepted linearity in the range of 5-150 ng/mL, with a limit of detection at 1.251 ng/mL. The method offers a broader and more sensitive detection range compared with a previous UHPLC method. Additionally, the environmental friendliness of the described method was conducted and compared with the reported UHPLC method using the analytical eco-scale and the analytical greenness metric. The results demonstrate that the current method exhibits higher levels of sustainability compared with the previously reported method.