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Steroid hormones, botrydial, and inorganic ions were studied from cold and hot tap water samples with capillary electrophoresis techniques using UV detection. Identification of the steroids and botrydial was made with ultra-high -performance liquid chromatography (UHPLC) coupled to electrospray ionization orbitrap high-resolution mass spectrometry. Solid phase extraction with nonpolar and ion-exchange sorbents was needed to enrich the compounds for CE and UHPLC studies. The steroids identified from the drinking water samples were estradiol glucoside, androstenedione, testosterone, and progesterone. However, only progesterone could be quantified in both cold and hot tap water samples from Helsinki households. Its concentration varied from 0.031 ng/L to 0.135 ng/L and from 0.054 ng/L to 0.191 ng/L, respectively. Chloride and nitrate amounts were 25 mg/L. Calcium, potassium, magnesium, and sodium were 20, 1, 1, and 17 mg/L at the highest, respectively. Copper, iron, sulphate, and ammonium were below the methods concentration limits. Botrydial from Botrytis cinerea mould was identified in all drinking waters. In both cold and hot tap waters its concentration was 861-3900% higher than in a drilled well water that was also used as the household tap water. The mould was also confirmed by identification of its metabolite abscisic acid. (C) 2017 Elsevier B.V. All rights reserved.

International audience; In order to highlight the importance of the complex stoichiometry during ion imprinted polymer (IIP) synthesis, we investigated the effect of the complex structure on IIPs selectivity by adjusting the complex stoichiometry before polymerization. 2-(aminomethyl)pyridine monomer (amp) was chosen as a functionalized ligand for nickel(II) ions and a polymerizable vinylbenzyl derivative (Vbamp) was prepared. Complex formation was studied by varying the nickel/Vbamp ratio and recording absorption spectra of the complexes at the polymerization conditions. Using a least-squares minimization scheme, the complex species distribution was successfully established. From these results, it was possible to choose the metal/ligand stoichiometry in the complex (1:1; 1:2 or 1:3) by adjusting the initial metal/ligand ratio. IIPs were then prepared by inverse suspension copolymerization of Vbamp with ethyleneglycol dimethacrylate (EDMA). Highly porous particles with good nickel binding capacity and good Ni/Zn selectivity even at acidic conditions were obtained. Equilibrium uptake of Ni(II) at pH 7 ranged from 0.12 to 0.2 mmol g−1 and relative selective coefficient was as high as 260 for the IIP prepared using the Ni(Vbamp)2 complex.

Complexation of Ni2+ with 2-(aminomethyl)pyridine (amp) has been studied at 22 °C using absorption spectroscopy. Effect of high Zn2+ concentration on complex formation in aqueous sulfate solutions and complexation of Ni(ClO4)2 with amp in a nonaqueous methanol/2-methoxyethanol mixture were investigated. The spectra were analyzed using least-squares minimization technique (LS) and partial least-squares method (PLS) to obtain the stability constants and distribution of the complex species. Moreover, complex formation was studied qualitatively by means of continuous variation analysis. The data measured at zinc concentrations of 0.100–1.84 mol·kg–1 indicate only minor deviations from the equilibria calculated using literature stability constants. At the highest zinc concentration, the equilibrium is slightly shifted to higher complexes but no evidence was found of changes in the octahedral complex geometry. Octahedral 1:1, 1:2, and 1:3 complexes were observed also in the nonaqueous solvent mixture but the st...