On-site, rapid, and facile determination of gentamicin using a fluorescent resonance energy transfer sensor constructed from nitrogen-carbon quantum dots functionalized by 4,5-imidazole dicarboxylic acid

In this paper, NC QDs were obtained from agricultural waste (wheat straw), functionalized by 4,5-imidazole dicarboxylic acid and used to detect gentamicin in aqueous solution. The NC QDs were characterized by HRTEM, XPS, UV-Vis, etc. The fluorescence properties of the functionalized NC QDs for GEN detection were studied at λ_em = 385 nm. The fluorescence intensity showed a good linear relationship with the GEN concentration of samples (I = 343.10 + 30.07C, R² = 0.9896) for GEN concentrations ranging from 0 to 2.9 × 10^-4 mol/L. The sensing mechanism was found to be fluorescence resonance energy transfer (FRET) between the functionalized NC QDs and GEN. The results indicated that the method had good repeatability for GEN detection. The technology could be extended to biological detection.