Heterocyclic Coumarin Hybrids as Chemo Sensors of Neurotoxic Lead Ions in Safe Harmless Solvents and Ambient Temperature.

Lead is a highly toxic poison for the human body. Lead poisoning is a fatal condition severely affecting the mental and physical development of children younger than 4-5 years. Among various chemo sensors, heterocyclic derivatives are widely used to chelate toxic metal ions, leading to changes in their optical, absorbance, and spectroscopic properties. In this study, coumarin heterocyclic hybrids C1-C6 were synthesized by reacting different classes of amine, pyrrole, and thiadiazoles with bromo acetyl coumarin at room temperature. The C1-C6 probes are studied for their metal binding ability in aqueous acetonitrile for Cu2+, Ni2+, Mn2+, Pb2+, and Zn2+ ions. All six probes showed significant binding with Pb2+ ions with good selectivity by UV-visible, NMR, and HPLC studies. The high binding constants and efficiency of probes between 0.00003-0.00006 range further point to their likely use in human biomatrix' s for Pb2+ detection.