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Inclusion compounds formed between sertraline stereoisomers and β-cyclodextrin, and 2-hydroxypropyl-β-cyclodextrin, were analyzed by using quantum chemistry methods.

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Guanosine triphosphate (GTP) is a key biomarker of multiple cellular processes and human diseases. The new fluorescent dinuclear complex [Zn 2 (L)(S)][OTf] 4 , 1 (asymmetric ligand, L = 5,8-Bis{[bis(2-pyridylmethyl)amino] methyl}quinoline, S = solvent, and OTf = triflate anion) was synthesized and studied in-depth as a chemosensor for nucleoside polyphosphates and inorganic anions in pure water. Additions at neutral pH of nucleoside triphosphates, guanosine diphosphate, guanosine monophosphate, and pyrophosphate (PPi) to 1 quench its blue emission (λ em = 410 nm) with a pronounced selectivity toward GTP over other anions, including adenosine triphosphate (ATP), uridine triphosphate (UTP), and cytidine triphosphate (CTP). The efficient quenching response by the addition of GTP was observed in the presence of coexisting species in blood plasma and urine with a detection limit of 9.2 μmol L −1 . GTP also shows much tighter binding to the receptor 1 on a submicromolar level. On the basis of multiple spectroscopic tools ( 1 H, 31 P NMR, UV−vis, and fluorescence) and DFT calculations, the binding mode is proposed through three-point recognition involving the simultaneous coordination of the N 7 atom of the guanosine motif and two phosphate groups to the two Zn(II) atoms. Spectroscopic studies, MS-ESI, and DFT suggested that GTP bound to 1 in 1:1 and 2:2 models with high overall binding constants of log β 1 (1:1) = 6.05 ± 0.01 and log β 2 = 10.91 ± 0.03, respectively. The optical change and selectivity are attributed to the efficient binding of GTP to 1 by the combination of a strong electrostatic contribution and synergic effects of coordination bonds. Such GTP selectivity of an asymmetric metal-based receptor in water is still rare.

The removal of pathogenic organisms from water and wastewater by electrochemical methods has gained increasing attention due to their very high efficiency, and their easy applicability in real world processes. In this regard there are several approaches utilizing different electrode materials to accomplish the pollutant removal. This minireview highlights how electrocoagulation, direct electrooxidation and indirect electrooxidation are used to remove pathogenic microorganisms from different water and wastewater sources, including industrial and municipal water and wastewater. The conditions for each treatment are describe and the material used for the electrodes are discussed. Particular attention is paid to the use of boron-doped electrodes in such processes. This kind of electrodes have gained attention due to their excellent properties in electrochemical water treatment, including a wide electrochemical potential window in aqueous media, very low capacitance and extreme electrochemical stability.

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In the present investigation, four macrophytes, namely Typha latifolia (L.), Lemna minor (L.), Eichhornia crassipes (Mart.) Solms-Laubach, and Myriophyllum aquaticum (Vell.) Verdc, were evaluated for their heavy metal (Cu, Pb, Hg, and Zn) hyperaccumulation potential under laboratory conditions. Tolerance analyses were performed for 7 days of exposure at five different treatments of the metals mixture (Cu, Hg, Pb, and Zn). The production of chlorophyll and carotenoids was determined at the end of each treatment. L. minor revealed to be sensitive, because it did not survive in all the tested concentrations after 72 hours of exposure. E. crassipes and M. aquaticum displayed the highest tolerance to the metals mixture. For the most tolerant species of aquatic macrophytes, The removal kinetics of E. crassipes and M. aquaticum was carried out, using the following mixture of metals: Cu (0.5 mg/L) and Hg, Pb, and Zn 0.25 mg/L. The obtained results revealed that E. crassipes can remove 99.80% of Cu, 97.88% of Pb, 99.53% of Hg, and 94.37% of Zn. M. aquaticum withdraws 95.2% of Cu, 94.28% of Pb, 99.19% of Hg, and 91.91% of Zn. The obtained results suggest that these two species of macrophytes could be used for the phytoremediation of this mixture of heavy metals from the polluted water bodies.

Inductive and resonance effects of different substituents (CH3, Cl, NH3, CN, NO2) on the reactivity of the nitrogen and oxygen centers of several saturated and unsaturated hydroxylamine derivates toward hard and soft electrophiles are analyzed in terms of various conceptual DFT based descriptors calculated using B3LYP/6-311G** method. In most cases, the +/-I and +/-M effects are correctly described by these descriptors. The way the substituent effect dies down as the distance between the substituent and the active center increases is also analyzed. It is observed that more than one effect is to be considered to properly understand the effect of a substituent on reactivity.