Poly(Azomethine-urethane)-based Fluorescent Chemosensor for the Detection of Cr³⁺ Cations in Different Water Samples

A highly selective, and effective poly(azomethine-urethane)-based chemosensor (HIMA) was prepared, and it used as a fluorescent sensor for the detection of Cr³⁺ cations in different solutions. The HIMA was prepared in two-step reactions by using hexamethylene diisocyanate, 2,4-dihydroxy benzaldehyde, and 2-aminophenol. The sensitivity and selectivity of the fluorescent probe were tested in the presence of different metal ions. The obtained findings indicated that the chemosensor exhibited a quenching effect against the only Cr³⁺ ion. The limit of detection (LOD) and limit of quantitation (LOQ) of the chemosensor HIMA were calculated as 7.98 × 10^-7 M, and 2.42 × 10^-6 M, respectively. In addition, the binding constant (Ka) of the chemosensor was calculated as 5.31 × 10⁵ M^-1.