A Green Probe-Free Spectrofluorimetric Platform for Trace Detection of Organophosphate Pesticide in Water Leveraging...

A new green spectrofluorimetric method was created for the detection of the organophosphate pesticide chlorpyrifos (CPS) in water with great sensitivity. The probe-free approach leverages the direct formation of a host-guest inclusion complex with β-cyclodextrin (β-CD) to greatly improve the native fluorescence of CPS. This strategy eliminates the need for toxic reagents or derivatization steps. The complex had a 1:1 stoichiometry and a high binding constant of 2.6 × 10³ L/mol. Molecular docking showed a free energy of -6.024 kcal/mol, stabilized by hydrogen bonds and hydrophobic interactions. The method showed high sensitivity (LOD = 0.07 μM) over a wide linear range (0.15-5.4 μM, r² = 0.9994) and high accuracy (97%-102% recovery) in tap, river, and irrigation water samples. Using a tri-color assessment protocol, we carefully tested how green, practical, and sustainable the method was. It got great scores for its greenness (AGREE = 0.78), practicality (BAGI = 70), and analytical performance (RAPI = 85). A thorough comparison with other methods using the Need, Quality, and Sustainability (NQS) index and AGREE scoring showed that this supramolecular strategy offers a strong balance of practical usefulness, analytical quality, and environmental friendliness.