Sharif, ShahzadShahbaz, MuhammadSahin, OnurKhurshid, Muhammad AqibAnbar, Maryam MusaffaDar, Birra2025-03-232025-03-2320241053-05091573-4994https://doi.org/10.1007/s10895-023-03484-whttps://hdl.handle.net/11486/6907A ligand, 2-phenylphthalazin-1(2H)-one (K), was synthesized by refluxing 2-formylbenzoic acid with phenyl hydrazine in presence of ethanol. FTIR, elemental analysis and single crystal XRD techniques were used to elucidate the structure. Fluorimetric turn-off response was recorded when solution of ligand (K) in DMF was treated with aqueous solution of Fe3+ and Fe2+ metal ions. No specific changes were observed on addition of other metal ions (Pb2+, Cd2+, Mn2+, Zn2+, Ba2+, Ni2+, Al3+, Ag1+, Co2+, Ca2+, Cu2+, Mg2+, Cr3+). Limit of Detection (LOD) was calculated for Fe-2 and Fe(3+)as 2.4 mu M and 2.5 mu M respectively, which is quite below to the recommended value 5.4 mu M of the Environment Protection Agency of USA. Association constants for Fe3+ and Fe2+ metal ions were determined as 6x10(-4) M-1 and 3.6x10(-4) M-1 respectively. Benesi-Hildebrand plot confirmed 1:1 binding ratio between metal ions and ligand.eninfo:eu-repo/semantics/openAccessSchiff baseSingle XRDChemosensorTurn off fluorescenceFe3+ and Fe2+Article3462783279110.1007/s10895-023-03484-w379102702-s2.0-85175370327Q3WOS:001095245800001Q2