الفهرس 
CHAPTER I Introduction and literature surveyOnly 14 pages are availabe for public view
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Abstract
3-Acetyl-4-hydroxy coumarin (AHC) and its transition (Cu2+, Ni2+, Co2+, Cd2+ and Zn2+) and lanthanide (Eu3+, Sm3+ and Tb3+) nanocomplexes were prepared. The ligand and its metal complexes were characterized with different techniques such as 1H-NMR, Mass spectrometer, elemental analysis, TGA, TEM, FT-IR, ESR and XRD. The absorption and photoluminescence spectra as well as electrical conductivity and magnetic moment were also measured. The reaction of AHC with transition metals produced complexes of 1:2 (M:L) and 1:3 stoichiometry with lanthanide ions. The spectral results revealed that the AHC coordinated the central metal ions in a monoanionic bidentate manner. The cytotoxic behavior of the ligand and its transition metal complexes was evaluated against HepG-2 cell lines. The cytotoxic study revealed that Zn-AHC complex showed significant activity IC50 = 3.87 µg/ml) compared with different standard drugs. Additionally, using UV-Vis spectroscopy, the binding characteristics of AHC and its transition metal complexes with HS-DNA revealed a moderately strong interaction depending on the intercalative binding mode. The interaction of AHC and its transition metal complexes with DNA has also been investigated via molecular docking simulation. DNA cleavage study has been, moreover, carried out by agarose gel electrophoresis for highly active Cu-AHC and Zn-AHC complexes. The DFT calculations validated the suggested structures and were used to calculate chemical quantum parameters and supported the biological findings.
The highly luminescent AHC powder was applied for latent print detection from various forensic substrates.
Moreover, Eu3+, Sm3+ and Tb3+ complexes (M-AHC) were characterized with intense photoluminescence emission and long lifetime. The Eu-AHC and Sm-AHC nanocomplexes were tested as a sensor for ions (anions and cations) in ground state and excited state. It is noted that Eu-AHC nanosensor is selective to Cr3+ ion in ground state (LOD = 5.594x10-5 mol/L). The selectivity of Eu-AHC and Sm-AHC nanosensors toward ions were also studied by photoluminescence quenching method. Eu-AHC nanosensor showed high selectivity, fast response time with low interference in case of Al3+ (85%) and PO43- (97.5%). LOD of Al3+ and PO43+ using the prepared Eu-AHC nanosensor are 0.797x10-5 molL-1 and 0.633x10-5 molL-1, respectively. The PL data demonstrated that the nanosensor has been statically quenched via columbic interaction mechanism between the europium ion and quencher.
Moreover, Tb-AHC shows high selectivity towards oxytetracycline, and ciprofloxacine antibiotics with LOD values equal 0.6811x10-5 molL-1 and 1.679x10-5 molL-1, respectively. The PL lifetime and critical distance results demonstrated that the fluorescent sensor has been dynamically quenched via columbic interaction mechanism between the green Tb-AHC nanosensor and antibiotics. The proposed method was efficiently used to determine oxytetracycline and ciprofloxacine in its commercial tablet formulation (Tetracycline capsules 250 mg and Cipro 500 mg tablets).