Highly Stable Photoluminescent CeF ₃ Nanocrystal as a Versatile Probe for Neurotoxic Alkaloid (Anabasine) Sensing via Fluorescence Modulation

This study introduces highly stable photoluminescent CeF₃ nanocrystals as a first ratiometric fluorescent probe for the selective detection of the neurotoxic alkaloid anabasine in environmental water matrices. The hexagonal-phase CeF₃ nanocrystals (40-50 nm) exhibit dual-emission bands at 322 (quenched) and 433 nm (enhanced) upon anabasine binding, enabling sensitive (LOD: 0.17 μM) and matrix-resistant quantification. Structural (XRD, TEM, EDS) and optical (pH and thermal stability: pH 4-10, 30-90 °C) characterizations confirm robustness for real-world applications. Recovery assays (95-103%) in lake, river, and tap water demonstrate minimal matrix interference, outperforming LC-MS/MS and GC-FID methods that require derivatization or complex sample pretreatment. The cost-effectiveness, simplicity, and ratiometric self-calibration of the method highlight its potential for on-site environmental monitoring of tobacco-derived contaminants.