Fluorescent [Nd(Anth)₃(H₂O)₃] Complex for determination of some β-lactam antibiotics

A luminous neodymium (III) complex, [Nd(Anth)3(H₂O)2], which contains anthranilate ligands, was synthesized and tested as a fluorescent probe for spectrofluorometric detection of three commonly used β-lactam antibiotics; amoxicillin, cefixime, and cephalexin. The addition of these antibiotics greatly quenched the complex's high near-infrared (NIR) emission when excited by UV light. Reproducible, selective, and concentration-dependent fluorescence quenching response was recorded. Linear ranges of 0.1–6.0 µM, 0.2–1.0 µM, and 0.1–6.0 µM for amoxicillin, cefixime, and cephalexin, respectively were recorded with correlation coefficients (R) > 0.98. Competitive limits of detection (LOD) of 0.0980 µg/ml, 0.0025 µg/ml, and 0.1020 µg/ml were captured for amoxicillin, cefixime, and cephalexin, respectively. Analytical parameters such as recovery and RSD were confirmed for the pharmaceuticals without any sophisticated equipment or intricate sample preparation needed in aqueous environments. These findings demonstrate the potential of [Nd(Anth)3(H₂O)2] complex as an optical sensor for β-lactam antibiotics that is both sensitive and selective, offering a useful instrument for environmental monitoring and pharmaceutical quality control. The technique might be used successfully to routinely identify these antibiotics in commercial tablet formulations.