Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
Add more filters










Publication year range
1.
Sci Total Environ ; 941: 173763, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38839004

ABSTRACT

In recent years, nanocopper (Cu NPs) has gained attention due to its antimicrobial properties and potential for industrial, agricultural, and consumer applications. But it also has several effects on the aquatic environment. Widespread use of various nanoproducts has raised concerns about impacts of different nanoparticle size on environment and biological objects. Spermatozoa is a model for studying the ecotoxic effects of pollutants on cells and organisms. This study aimed to investigate the effects of different sizes of copper nanoparticles on rainbow trout spermatozoa motility, and to compare their effects with copper ionic solution. Computer assisted sperm analysis (CASA) was used to detect movement parameters at activation of gametes (direct effect) with milieu containing nanocopper of primary particle size of 40-60, 60-80 and 100 nm. The effect of the elements ions was also tested using copper sulfate solution. All products was prepared in concentration of 0, 1, 5, 50, 125, 250, 350, 500, 750, and 1000 mg Cu L-1. Six motility parameters were selected for analysis. The harmful effect of Cu NPS nanoparticle was lower than ionic form of copper but the effect depends on the motility parameters. Ionic form caused complete immobilization (MOT = 0 %, IC100) at 350 mg Cu L-1 whilst Cu NPs solution only decreased the percentage of motile sperm (MOT) up to 76.4 % at highest concentration tested of 1000 mg Cu L-1 of 40-60 nm NPs. Cu NPs of smaller particles size had more deleterious effect than the bigger one particularly in percentage of MOT and for curvilinear velocity (VCL). Moreover, nanoparticles decrease motility duration (MD). This may influence fertility because the first two parameters positively correlate with fertilization rate. However, the ionic form of copper has deleterious effect on the percentage of MOT and linearity (LIN), but in some concentrations it slightly increases VCL and MD.


Subject(s)
Copper , Metal Nanoparticles , Oncorhynchus mykiss , Particle Size , Sperm Motility , Spermatozoa , Water Pollutants, Chemical , Animals , Male , Oncorhynchus mykiss/physiology , Sperm Motility/drug effects , Copper/toxicity , Water Pollutants, Chemical/toxicity , Spermatozoa/drug effects , Spermatozoa/physiology , Metal Nanoparticles/toxicity
2.
J Am Chem Soc ; 145(36): 19533-19541, 2023 Sep 13.
Article in English | MEDLINE | ID: mdl-37642307

ABSTRACT

The environment around a host-guest complex is defined by intermolecular interactions between the complex, solvent molecules, and counterions. These interactions govern both the solubility of these complexes and the rates of reactions occurring within the host molecules and can be critical to catalytic and separation applications of host-guest systems. However, these interactions are challenging to detect using standard analytical chemistry techniques. Here, we quantify the hydration and ion pairing of a FeII4L4 coordination cage with a set of guest molecules having widely varying physicochemical properties. The impact of guest properties on host ion pairing and hydration was determined through microwave microfluidic measurements paired with principal component analysis (PCA). This analysis showed that introducing guest molecules into solution displaced counterions that were bound to the cage, and that the solvent solubility of the guest has the greatest impact on the solvent and ion-pairing dynamics surrounding the host. Specifically, we found that when we performed PCA of the measured equivalent circuit parameters and the solubility and dipole moment, we observed a high (>90%) explained variance for the first two principal components for each circuit parameter. We also observed that cage-counterion pairing is well-described by a single ion-pairing type, with a one-step reaction model independent of the type of cargo, and that the ion-pairing association constant is reduced for cargo with higher water solubility. Quantifying hydration and cage-counterion interactions is a critical step to building the next generation of design criteria for host-guest chemistries.

3.
J Chem Phys ; 156(15): 154501, 2022 Apr 21.
Article in English | MEDLINE | ID: mdl-35459289

ABSTRACT

We present here the results of high-pressure broadband dielectric spectroscopy (BDS) measurements for a mixture of liquid-crystalline drug itraconazole (ITZ) and glycerol (GLY) at a critical concentration of 5% w/w in which the nematic order is eliminated. In the investigated system, smectic-A to isotropic phase transition leaves a clear fingerprint on the dielectric response, allowing for a phase diagram creation using BDS data. By following the α-relaxation dynamics under different thermodynamic conditions, we provide insights into the effect of pressure on temperature and the phenomenology of smectic-A to the isotropic phase transition. Additional measurements of specific volume as a function of pressure and temperature provide us with a deeper insight into material properties that could be analyzed comprehensively via the equation of state. We proved the validity of the density scaling concept, showing that the mixture's complexity does not exclude thermodynamic scaling of dynamic properties related to the α-process in the smectic-A phase. The low value of scaling exponent γ = 2.00 ± 0.02 and a high ratio of the activation energy at constant volume, EV, to the activation enthalpy at constant pressure, HP, indicate that temperature is a dominant variable controlling α-relaxation dynamics in the ordered smectic-A phase of the ITZ-GLY mixture.


Subject(s)
Itraconazole , Liquid Crystals , Glycerol , Itraconazole/chemistry , Liquid Crystals/chemistry , Molecular Dynamics Simulation , Phase Transition
4.
J Hazard Mater ; 427: 128160, 2022 04 05.
Article in English | MEDLINE | ID: mdl-34979392

ABSTRACT

Ionic liquids (ILs) are known for their unique physicochemical properties. However, despite the great number of published papers, still little attention has been paid to their biological activity. Anticancer potential and the molecular mechanisms underlying the toxicity of these compounds are especially interesting and still unexplored. In the current work, a broad analysis of the cytotoxicity towards colon and breast cancers as well as glioblastoma of the ILs with pyridinium, piperidinium, pyrrolidinium, and imidazolium cations and trifluoromethanesulfonate or bis(trifluoromethylsulfonyl)imide anions indicated previously as the most toxic for normal human dermal fibroblasts were presented. In the case of MCF-7 cells, the activity of 1-decyl-3-methylimidazolium trifluoromethanesulfonate was more than twice as high as cisplatin. It was found that the inhibition of the cell cycle of colon cancer and glioblastoma cells occurs in different phases. More importantly, the different types of cell death were detected for both selected ILs, namely 1-hexyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide and 1-hexyl-3-methylimidazolium trifluoromethane-sulfonate, on colon cancer and glioblastoma, respectively, apoptosis and autophagy, confirmed at the gene and protein levels. Additionally, kinetic studies of the reactive oxygen species indicated that the tested ILs disturbed the cellular redox homeostasis.


Subject(s)
Ionic Liquids , Anions , Humans , Imides , Kinetics , Mesylates
5.
J Phys Chem B ; 125(16): 4141-4147, 2021 Apr 29.
Article in English | MEDLINE | ID: mdl-33857379

ABSTRACT

In this work, we show how the structure and intermolecular interactions affect the dynamic heterogeneity of aprotic ionic liquids. Using calorimetric data for 30 ionic samples, we examine the influence of the strength of van der Waals and Coulombic interactions on dynamic heterogeneity. We show that the dynamic length scale of spatially heterogeneous dynamics decreases significantly with decreasing intermolecular distances. Additionally, we assume that the magnitude of the number of dynamically correlated molecules at the liquid-glass transition temperature can be treated as an indicator for a dynamical crossover.

6.
J Phys Chem Lett ; 12(8): 2142-2147, 2021 Mar 04.
Article in English | MEDLINE | ID: mdl-33625856

ABSTRACT

A series of five alcohols (3-methyl-2-butanol, 1-cyclopropylethanol, 1-cyclopentylethanol, 1-cyclohexylethanol, and 1-phenylethanol) was used to study the impact of the size of steric hindrance and its aromaticity on self-assembling phenomena in the liquid phase. In this Letter, we have explicitly shown that the phenyl ring exerts a much stronger effect on the self-organization of molecules via the O-H···O scheme than any other type of steric hindrance, leading to a significant decline in the size and concentration of the H-bonded clusters. Given the combination of calorimetric, dielectric, infrared, and diffraction studies, this phenomenon was ascribed to its additional proton-acceptor function for the competitive intermolecular O-H···π interactions. The consequence of this is a different packing of molecules on the short- and medium-range scale.

7.
Soft Matter ; 16(41): 9479-9487, 2020 Oct 28.
Article in English | MEDLINE | ID: mdl-32955538

ABSTRACT

The glassy, supercooled, and normal liquid states of the 1-alkyl-3-methylimidazolium tricyanomethanide series [CnC1im][TCM] (n = 2, 4, 6, 8, and 16) were investigated by dielectric and mechanical (rheological) experiments supplemented by X-ray diffraction. The conductivity relaxation was found to be accompanied by a pronounced secondary relaxation. However, based on ambient and high-pressure results as well as the coupling model, we assumed that the latter one can not be classified as Johari-Goldstein relaxation. Moreover, the studies on the nanoscale organization of ionic liquids indicated that 1-alkyl-3-methylimidazolium tricyanomethanide ILs begin to form nanoscale aggregates when the alkyl chain of the cation has six carbon atoms.

8.
Phys Chem Chem Phys ; 22(34): 19342-19348, 2020 Sep 08.
Article in English | MEDLINE | ID: mdl-32822445

ABSTRACT

In this paper, we investigate the interplay between the dynamics and thermodynamics of aprotic ionic liquids in the supercooled and normal liquid states. For this purpose, the conductivity dynamic modulus Mσp-T, being defined as the ratio of activation energy (Ep) and activation volume (VT), and its relation to bulk modulus BT under isobaric and isothermal conditions is examined. We found that both isobaric cooling and isothermal compression lead to an increase in Mσp-T. Specifically, Mσp-T(P)T rises linearly similar to BT. Consequently, a direct linear relationship between Mσp-T(P)T and BT is established under isothermal conditions.

9.
Sci Total Environ ; 745: 141032, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-32726691

ABSTRACT

Plants are masterpieces of evolution that is based on carbon chemistry. In particular, plant leaves are biosynthetic factories able to convert CO2 into carbohydrates and oxygen. It is worth noting that mimicking the efficiency of a natural plant and natural leaf is still a challenge for contemporary chemistry. We can even better realize this when we notice that a plant and an industrial factory are equivalent in meaning. On the other hand, green technologies are under development in a quest for the artificial leaf. If we could modify the synthetic pathways in leaves, we could also design green chemistry schemes in natural leaves to produce useful chemicals or to digest wastes or toxins. Specifically, can we intensify the potential for capturing atmospheric CO2 in leaves? Auxins are plant hormones that control the growth and development of plants. Herein, we determined whether we could efficiently transport xenobiotic auxin into leaves and if so, whether this supply could enhance the metabolism and CO2 capturing ability. By exploring a series of dioxolanes as potential enhancers of auxin transport, we discovered for the first time that a small molecular compound, 2,2-dimethyl-1,3-dioxolane (DMD), enhances the xenobiotic auxin transport to leaves, which boosts the metabolism that is measured by H2O2 production as well as CO2 capturing ability in leaves.


Subject(s)
Carbon Dioxide , Indoleacetic Acids , Biological Transport , Hydrogen Peroxide , Photosynthesis , Plant Leaves
10.
ACS Macro Lett ; 8(8): 996-1001, 2019 Aug 20.
Article in English | MEDLINE | ID: mdl-35619493

ABSTRACT

In this paper, we examine the transport properties of a 1,2,3-triazolium-based poly(ionic liquid) (PIL) at ambient and elevated pressure up to 475 MPa. We show that the isothermal and isobaric conductivity measurements analyzed in the 3D plane give a unique possibility to estimate the thermodynamic (isothermal compressibility and thermal expansion coefficient) properties for PILs having a charge transport fully controlled by viscosity. This result, providing a direct connection between thermodynamic and dynamic properties of PILs, is of significant importance for both material scientists and practical applications.

11.
J Phys Chem B ; 121(42): 9886-9894, 2017 10 26.
Article in English | MEDLINE | ID: mdl-28950058

ABSTRACT

Ultrasound absorption spectra within the frequency range 10-300 MHz were determined for 1-propyl- and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imides at ambient pressure and at temperatures in the ranges 293.15-313.15 and 293.15-323.15 K, respectively. For both compounds, a single Debye model (relaxation times between 0.451 and 0.778 ns) thoroughly describes the observed ultrasound absorption spectra in the investigated ranges. The spectra resemble those observed for imidazolium-based ionic liquids with the same anion. The ultrasound relaxation is dependent on the alkyl chain length of pyrrolidinium ring. In comparison to adequate imidazolium-based bis(trifluoromethylsulfonyl)imides, the relaxation in pyrrolidinium-based bis(trifluoromethylsulfonyl)imides is stronger; the pyrrolidinium cation causes clearly greater absorption than the imidazolium cation. Also, estimated ultrasound velocity dispersion is stronger in the case of pyrrolidinium imides in comparison to imidazolium imides. In turn, comparison of the ultrasonic data and literature data for the dielectric spectra exemplified for the 1-butyl- side chain in the cation indicates strong coupling in the case of imidazolium ring and weak coupling in the case of pyrrolidinium ring. The effect of absorption on the speed of sound is also discussed.

SELECTION OF CITATIONS
SEARCH DETAIL
...