Loading...
2 results
Search Results
Now showing 1 - 2 of 2
- Synthesis and characterization of a 3-hydroxy-4-pyridinone chelator functionalized with a polyethylene glycol (PEG) chain aimed at sequential injection determination of iron in natural watersPublication . Mesquita, Raquel; Moniz, Tânia; Miranda, Joana L. A.; Gomes, Vânia; Silva, André M. N.; Rodriguez-Borges, J. E.; Rangel, António O. S. S.; Rangel, MariaThe synthesis of a highly water soluble 3-hydroxy-4-pyridinone ligand, functionalized with a hydrophilic ethylene glycol chain (PEG-HPO), was successfully achieved and is reported together with that of its iron (III) complex. The improved hydrophilicity of both the PEGylated 3,4-HPO ligand and its iron(III) complex were fully investigated in an analytical application and, the new chelator is proposed for the spectrophotometric sequential injection determination of iron in waters. The new ligand provided better sensitivity and a lower LOD for iron determination than that obtained for N-alkyl-3-hydroxy-4-pyridinone ligands. The developed sequential injection method presents a dynamic working range of 0.10-1.00 mg Fell. with a LOD of 48 mu g/L. Due to the use of a sequential injection system, the overall effluent production was <2 mL corresponding to the consumption of 44 mu g of PEG-HPO, 0.71 mg of NaHCO3, 0.92 mg of HNO3 and 500 mu L of sample. Two reference samples were assessed for accuracy studies and a relative deviation <5% was obtained; eight waters samples were analyzed and the results compared with the reference procedure, and no statistical difference was observed for the two sets of results.
- New hydrophilic 3-hydroxy-4-pyridinone chelators with ether-derived substituents: synthesis and evaluation of analytical performance in the determination of iron in watersPublication . Moniz, Tânia; Cunha-Silva, Luís; Mesquita, Raquel B.R.; Miranda, Joana L.A.; Silva, André M.N.; Silva, Ana M.G.; Rangel, António O.S.S.; Castro, Baltazar de; Rangel, MariaThree new hydrophilic 3-hydroxy-4-pyridinone chelators containing ether-derived substituents were prepared by a more sustainable synthetic protocol that involves the use of microwave heating and commercially available amines, allowing the successful production of highly water soluble chelators with improved reaction yields and reaction times. Compared with parent 3-hydroxy-4-pyridinone ligands, the new compounds were obtained faster and in higher amounts, facilitating the scale up of the synthesis, which is crucial to produce these ligands and their respective iron(III) complexes for many biological, analytical and agricultural applications. Ligands were fully characterized by 1H and 13C Nuclear Magnetic Resonance, High Resolution Mass Spectrometry and Single Crystal X-Ray Diffraction and their performance in the analytical determination of iron(III) in water samples was evaluated by sequential injection methods. The results obtained are scientifically relevant, pointing out the potential of the new and straightforwardly synthesized ligands as analytical reagents for determination of iron(III).