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The adsorption of permeating chemical compounds on the textile materials active surface is one of many principles of personal protection against dangerous chemical compounds including chemical warfare agents. The adsorption principle is generally known. However, its effective application especially in connection with the enhancing protection efficacy follows certain significant rules. A development of new textile materials based on the application of adsorbents in the combination with nanofibrous materials is the main topic of contemporary research in this area. This contribution sums up the theoretical basis of adsorption-based protective efficacy and also brings new experimental results of sorption and permeation of live CWA agents and their simulants through different samples of layered composite materials. Results are related to the basic structural parameters of nanotextiles and applied adsorbents.

H(3)nota derivatives are among the most studied macrocyclic ligands and are widely used for metal ion binding in biology and medicine. Despite more than 40 years of chemical research on H(3)nota, the comprehensive study of its solution chemistry has been overlooked. Thus, the coordination behavior of H(3)nota with several divalent metal ions was studied in detail with respect to its application as a chelator for copper radioisotopes in medical imaging and therapy. In the solid-state structure of the free ligand in zwitterionic form, one proton is bound in the macrocyclic cavity through a strong intramolecular hydrogen-bond system supporting the high basicity of the ring amine groups (log K-a = 13.17). The high stability of the [Cu(nota)](-) complex (log K-ML = 23.33) results in quantitative complex formation, even at pH Na(I) > K(I)). Thus, H(3)nota shows high selectivity for small metal ions. The [Cu(nota)](-) complex is hexacoordinated at neutral pH, and the equatorial N2O2 interaction is strengthened by complex protonation. Detailed kinetic studies showed that the Cu(II) complex is formed quickly (millisecond time scale at c(Cu) approximate to 0.1 mM) through an out-of-cage intermediate. Conversely, conductivity measurements revealed that the Zn(II) complex is formed much more slowly than the Cu(II) complex. The Cu(II) complex has medium kinetic inertness (tau(1/2) 46 s; pH 0, 25 degrees C) and is less resistant to acid-assisted decomplexation than Cu(II) complexes with H(4)dota and H(4)teta. Surprisingly, [Cu(nota)](-) decomplexation is decelerated in the presence of Zn(II) ions due to the formation of a stable dinuclear complex. In conclusion, H(3)nota is a good carrier of copper radionuclides because the [Cu(nota)](-) complex is predominantly formed over complexes with common impurities in radiochemical formulations, Zn(II) and Ni(II), for thermodynamic and, primarily, for kinetic reasons. Furthermore, the in vivo stability of the [Cu(nota)](-) complex may be increased due to the formation of dinuclear complexes when it interacts with biometals.

Eu(III) ternary complexes with 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (H3DO3A) and picolinate-like “antenna” ligands ([Eu(DO3A)(L)]−) react with carbonate anion to form more stable [Eu(DO3A)(CO3)]2− complexes which are non-fluorescent. Furthermore, [Eu(DO3A)(L)]− and [Eu(DO3A)(CO3)]2− differ in their electrochemical behavior. [Eu(DO3A)(L)]− are therefore suggested as sensitive luminescence-based and also electrochemical sensors of carbonate anion. Both luminescence and voltammetric sensing strategies show similar analytical figures of merit (limit of detection 0.2 mM, dynamic range 0.2–1.6 mM). The voltammetric procedure was successfully tested in field conditions for the quantitative analysis of bicarbonate/carbonate in environmental water samples, utilizing portable potentiostat and screen-printed electrode.

The kinetic properties of Cu(ii) complexes of H4dota and its analogues with one (H5do3ap), two in the 1,7-position (trans-H6do2a2p), three (H7doa3p) and four (H8dotp) phosphonic acid pendant arms were investigated. The formation of a Cu(ii) complex with H4dota, trans-H6do2a2p and H8dotp at a slightly acidic pH is faster for the phosphonic acid derivatives than for H4dota, but with no simple dependence on the number of -CH2PO3H2 substituents (trans-H6do2a2p > H8dotp > H4dota; pH 4-6). Relative differences in the reactivity among the differently protonated species (HnL(x-)) of the same ligand are successively decreased with the more phosphonic acid groups in the ligand. The faster complexation is probably caused by the higher ability of phosphonates to bind the metal ion and/or to assist in the transfer of protons from the ring amine groups to the bulk water. The acid-assisted decomplexation kinetics of the complexes was followed in highly acidic solutions ([H(+)] = 0.01-5 M) and at different temperatures (15-70 °C) to determine the activation parameters of the reaction. The kinetic inertness of the Cu(ii) complexes follows the order: H4dota > H5do3ap > trans-H6do2a2p > H7doa3p > H8dotp. To obtain information on the influence of additional pendant arms, analogous data were obtained for trans-H2do2a. The ligand is less reactive than H4dota, but the kinetic inertness of its Cu(ii) complex is similar to that of the H4dota complex. As it was considered that the published thermodynamics data on the Cu(ii)-H8dotp system are probably incorrect, the system was re-investigated. It showed a very high stability for the [Cu(dotp)](6-) species and the easy formation of several Cu2L species in the presence of an excess of the metal ion. Also, the structure of the (H6doa3p)(-) anion in the solid state was determined. These experimental data demonstrate that the substitution of acetic acid pendant arms by methylphosphonic acid ones in H4dota-like ligands increases the rate of complexation but significantly decreases the kinetic inertness of the Cu(ii) complexes.

The mono(pyridine-N-oxide) analog of the H4dota macrocylic ligand, H3do3a-pyNO, is capable of forming thermodynamically stable and kinetically inert Ln(III) complexes. Its Eu(III) and Tb(III) complexes display a strong long-lived fluorescence as a result of the antenna effect of the pyridine- N-oxide fluorophore in the reagent. It is shown that H3do3a-pyNO can be used as a fluorogenic reagent for the determination of Eu(III) and Tb(III) at pH 6.5 and cL 1 mM. At an excitation wavelength of 286 nm, the emission maxima are 615 nm (Eu(III)-complex), and 547 nm (Tb(III)complex). Detection limits are at concentrations around 1.0 mM and linearity of the method spans over 2 orders of magnitude. The method was applied to artificial and real samples (spiked mineral waters, extracts from cathode ray tube luminophore dust) and gave satisfactory results. The method is simple, rapid, and hardly interfered by other metal ions.

The Electronegativity Equalization Method (EEM) is a fast approach for charge calculation. A challenging part of the EEM is the parameterization, which is performed using ab initio charges obtained for a set of molecules. The goal of our work was to perform the EEM parameterization for selected sets of organic, organohalogen and organometal molecules. We have performed the most robust parameterization published so far. The EEM parameterization was based on 12 training sets selected from a database of predicted 3D structures (NCI DIS) and from a database of crystallographic structures (CSD). Each set contained from 2000 to 6000 molecules. We have shown that the number of molecules in the training set is very important for quality of the parameters. We have improved EEM parameters (STO-3G MPA charges) for elements that were already parameterized, specifically: C, O, N, H, S, F and Cl. The new parameters provide more accurate charges than those published previously. We have also developed new parameters for elements that were not parameterized yet, specifically for Br, I, Fe and Zn. We have also performed crossover validation of all obtained parameters using all training sets that included relevant elements and confirmed that calculated parameters provide accurate charges.

The kinetics of decomposition of a macrocyclic Cu2+ complex is strongly dependent on the anions in solution. In particular, chloride anions accelerate significantly the decomposition process, even out of the stopped-flow time scale. Given the different chloride concentrations in biological media, the possibility of changes in the decomposition kinetics must be considered when designing 64Cu radiopharmaceuticals.

The kinetic inertness of copper(II) complexes with cyclen-based ligands having three (H3do3a) or four (H4dota) acetic acid arms and those with three acetic acid and one phosphonic (H5do3ap), phosphinic (H5do3apPrA, H4do3apABn) acid or methylpyridine-N-oxide (H3do3a-pyNox) pendant arms has been studied. The proton-assisted decomplexation reaction was studied under a wide range of conditions to fully assess the parameters influencing the reaction (temperature range 25–60 °C, proton concentration range 0.05–5 M and presence of perchlorate or nitrate anions). The empirical rate law kd,obs = k0 + kH × [H+], involving solvolytic and proton-assisted dissociation pathways, shows that the complexes can be divided into two groups according to their kinetic behavior. Complexes of ligands having only carboxylate pendant arms (H3do3a, H4dota) show higher kinetic inertness than those of ligands with mixed pendant arms (H5do3ap, H5do3apPrA, H4do3apABn, H3do3a-pyNox). Linear Free Energy Relationship (LFER) analysis of the activation parameters (ΔH#, ΔS#) proves that the reaction mechanism is generally the same for all copper(II) complexes and is independent of the inert electrolyte. Rate constants representing both solvolytic and acid-assisted pathways roughly correlate with the basicity of the ring nitrogen atoms. The nitrate anion from the supporting electrolyte was shown to accelerate (by about 3–5 times) the decomplexation reaction when compared to the reaction in perchlorate-containing media; the nitrate anion seems to interact with the reaction intermediates, changing the activation parameters of both reaction pathways. This effect is somewhat suppressed in the complex of the ligand with a hydrophobic p-aminobenzyl substituent on the phosphorus atom, H5do3apABn. In perchlorate media, complexes of the monophosphorus acid H4dota analogs are less kinetically inert (τ½ 2.4–4.8 h at pH 0, 25 °C) than the Cu(II)-H4dota complex (τ½ 32 h at pH 0, 25 °C).

Lanthanide(III) complexes of 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (H3DO3A) are suggested as sensors for sensitive luminescence-based determination of a carbonate anion. Thermodynamic study of association of [Eu(H2O)2(DO3A)] with bidentate anionic ligands using luminescence spectroscopy reveals an affinity order CO 3 2− > oxalate2− > picolinate− > phthalate2− ≈ citrate3−; presumably as a consequence of an increasing chelate ring size. The ternary [Eu(DO3A)(picolinate)]− and [Tb(DO3A)(picolinate)]− complexes show improved photophysical properties due to the antenna effect of the picolinate anion. High quenching effect of carbonate anion and, to a lesser extent also oxalate, enables construction of a linear calibration plot utilizing optimized experimental conditions (e.g. c LnL = 0.1 mM, c picolinate = 2–5 mM, pH = 7.4, λ exc = 286 nm, etc.) for carbonate determination in solution. Both sensors show a comparable sensitivity and the detection limit of about 0.4 mM. In order to improve the photophysical properties of Ln(III) sensor by shift of excitation wavelength about 40 nm to VIS range, the isoquinoline-3-carboxylic acid (IQCA) as antenna ligand was employed instead of picolinic acid. The analysis of commercial samples of European mineral waters was carried out and they were compared to the results obtained by capillary isotachophoresis to confirm there is no inherent (systematic) error to the present analysis. The Ln(III) sensor with IQCA is recommended since it has a better robustness than that with picolinate. The present analytical method is simple and rapid, and it is useful for sensitive determination of bicarbonate/carbonate concentration in water samples under aerobic conditions.

International audience; Complexes of 4,10-bis(phosphonomethyl)-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (trans-H(6)do2a2p, H(6)L) with transition metal and lanthanide(III) ions were investigated. The stability constant values of the divalent and trivalent metal-ion complexes are between the corresponding values of H(4)dota and H(8)dotp complexes, as a consequence of the ligand basicity. The solid-state structures of the ligand and of nine lanthanide(III) complexes were determined by X-ray diffraction. All the complexes are present as twisted-square-antiprismatic isomers and their structures can be divided into two series. The first one involves nona-coordinated complexes of the large lanthanide(III) ions (Ce, Nd, Sm) with a coordinated water molecule. In the series of Sm, Eu, Tb, Dy, Er, Yb, the complexes are octa-coordinated only by the ligand donor atoms and their coordination cages are more irregular. The formation kinetics and the acid-assisted dissociation of several Ln(III)-H(6)L complexes were investigated at different temperatures and compared with analogous data for complexes of other dota-like ligands. The [Ce(L)(H(2)O)](3-) complex is the most kinetically inert among complexes of the investigated lanthanide(III) ions (Ce, Eu, Gd, Yb). Among mixed phosphonate-acetate dota analogues, kinetic inertness of the cerium(III) complexes is increased with a higher number of phosphonate arms in the ligand, whereas the opposite is true for europium(III) complexes. According to the (1)H NMR spectroscopic pseudo-contact shifts for the Ce-Eu and Tb-Yb series, the solution structures of the complexes reflect the structures of the [Ce(HL)(H(2)O)](2-) and [Yb(HL)](2-) anions, respectively, found in the solid state. However, these solution NMR spectroscopic studies showed that there is no unambiguous relation between (31)P/(1)H lanthanide-induced shift (LIS) values and coordination of water in the complexes; the values rather express a relative position of the central ions between the N(4) and O(4) planes.

The novel methylphosphonic acid monoethylester (H(4)dotp(OEt)) has been synthesized and characterized and their complexes with Sm(III) and Ho(III) ions were studied. Dissociation constants of the ligand are lower than those of H(4)dota. The stability constants of the Ln(III)-H(4)dotp(OEt) complexes are surprisingly much lower that those of H(4)dota (H(4)dota=1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) probably due to a lower coordination ability of the phosphonate monoester groups. Acid-assisted decomplexation studies have shown that both complexes are less kinetically inert than the H(4)dota complexes, but still much more inert than complexes of open-chain ligands. Nevertheless, the synthesis of (153)Sm and (166)Ho complexes with this ligand led to stable complexes both in vitro and in vivo. A very low binding of these complexes to hydroxyapatite (HA) and calcified tissues was observed confirming the assumption that a fully ionized phosphonate group(s) is necessary for a strong bone affinity. Both complexes show similar behaviour in vivo and, in general, follow the biodistribution trend of the H(4)dota complexes with the same metals.