Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 52
Filter
1.
Molecules ; 29(13)2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38999093

ABSTRACT

Lithium-ion portable batteries (LiPBs) contain valuable elements such as cobalt (Co), nickel (Ni), copper (Cu), lithium (Li) and manganese (Mn), which can be recovered through solid-liquid extraction using choline chloride-based Deep Eutectic Solvents (DESs) and bi-functional ionic liquids (ILs). This study was carried out to investigate the extraction of metals from solid powder, black mass (BM), obtained from LiPBs, with various solvents used: six choline chloride-based DESs in combination with organic acids: lactic acid (1:2, DES 1), malonic acid (1:1, DES 2), succinic acid (1:1, DES 3), glutaric acid (1:1, DES 4) and citric acid (1:1, DES 5 and 2:1, DES 6). Various additives, such as didecyldimethylammonium chloride (DDACl) surfactant, hydrogen peroxide (H2O2), trichloroisocyanuric acid (TCCA), sodium dichloroisocyanurate (NaDCC), pentapotassium bis(peroxymonosulphate) bis(sulphate) (PHM), (glycine + H2O2) or (glutaric acid + H2O2) were used. The best efficiency of metal extraction was obtained with the mixture of {DES 2 + 15 g of glycine + H2O2} in two-stage extraction at pH = 3, T = 333 K, 2 h. In order to obtain better extraction efficiency towards Co, Ni, Li and Mn (100%) and for Cu (75%), the addition of glycine was used. The obtained extraction results using choline chloride-based DESs were compared with those obtained with three bi-functional ILs: didecyldimethylammonium bis(2,4,4-trimethylpentyl) phosphinate, [N10,10,1,1][Cyanex272], didecyldimethylammonium bis(2-ethylhexyl) phosphate, [N10,10,1,1][D2EHPA], and trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, [P6,6,6,14][Cyanex272]/toluene. The results of the extraction of all metal ions with these bi-functional ILs were only at the level of 35-50 wt%. The content of metal ions in aqueous and stripped organic solutions was determined by ICP-OES. In this work, we propose an alternative and highly efficient concept for the extraction of valuable metals from BM of LiPBs using DESs and ILs at low temperatures instead of acid leaching at high temperatures.

2.
Molecules ; 27(15)2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35956933

ABSTRACT

The extraction of metals from waste printed circuit boards (WPCBs) with ionic liquids (ILs), Deep Eutectic Solvents (DESs) and organophosphorous-based acid (Cyanex 272) has been presented. The study was undertaken to assess the effectiveness of the application of the new leaching liquids, and the new method of extraction of metals from the leachate and the solid phase with or without the leaching process. Solvent extraction from the liquid leachate phase has been studied in detail with popular ILs, such as tetraoctylphosphonium bromide, {[P8,8,8,8][Br] and tributyltetradecylphosphonium chloride, [P4,4,4,14][Cl] using Aqueous Biphasic Systems (ABS) method. Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, [P6,6,6,14][Cyanex272], ([P6,6,6,14][BTMPP]), trihexyltetradecylphosphonium thiocyanate, [P6,6,6,14][SCN], methyltrioctylammonium chloride (Aliquat 336), as well as bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex 272) were also used in the extraction of metals from the leachate. Two DESs (1) {choline chloride + lactic acid, 1:2} and (2) {choline chloride + malonic acid, 1:1} were used in the extraction of metals from the solid phase. The extraction behavior of metals with DESs was compared with that performed with three new bi-functional ILs: didecyldimethylammonium salicylate, [N10,10,1,1][Sal], didecyldimethylammonium bis(2-ethylhexyl) phosphate, [N10,10,1,1][D2EHPA], and didecyldimethylammonium bis(2,4,4-trimethylpentyl) phosphinate, [N10,10,1,1][Cyanex272]. The [P6,6,6,14][Cyanex272]/toluene and (Cyanex 272 + diethyl phosphite ester) mixtures exhibited a high extraction efficiency of about 50-90% for different metal ions from the leachate. High extraction efficiency of about 90-100 wt% with the ABS method using the mixture {[P8,8,8,8][Br], or [P4,4,4,14][Cl] + NaCl + H2O2 + post-leaching liquid phase} was obtained. The DES 2 revealed the efficiency of copper extraction, ECu = 15.8 wt% and silver, EAg = 20.1 wt% at pH = 5 from the solid phase after the thermal pre-treatment and acid leaching. The solid phase extraction efficiency after thermal pre-treatment only was (ECu = 9.6 wt% and EAg = 14.2 wt%). The use of new bi-functional ILs did not improve the efficiency of the extraction of metal ions from the solid phase. Process factors such as solvent concentration, extraction additives, stripping and leaching methods, temperature, pH and liquid/solid as well as organic/water ratios were under control. For all the systems, the selectivity and distribution ratios were described. The proposed extraction processes can represent alternative paths in new technologies for recovering metals from electronic secondary waste.


Subject(s)
Electronic Waste , Ionic Liquids , Acids , Choline , Electronic Waste/analysis , Hydrogen Peroxide , Ions , Silver , Solvents , Water
3.
Molecules ; 25(23)2020 Dec 02.
Article in English | MEDLINE | ID: mdl-33276551

ABSTRACT

Experimental and theoretical studies on thermodynamic properties of quinolinium-based ionic liquids (ILs) based on bis(trifluoromethylsulfonyl)imide anion (namely N-butyl-quinoloinium bis(trifluoromethylsulfonyl)imide, [BQuin][NTf2], N-hexylquinoloinium bis(trifluoromethyl-sulfonyl)imide, [HQuin][NTf2], and N-octylquinoloinium bis(trifluoromethyl-sulfonyl)imide, [OQuin][NTf2]) with aromatic sulfur compounds and heptane, as a model compound of fuel were examined in order to assess the applicability of the studied ionic liquids for desulfurization of fuels. With this aim, the temperature-composition phase diagrams of 13 binary mixtures composed of organic sulfur compounds (thiophene, benzothiophene, or 2-methylthiophene) or heptane and ionic liquid (IL) were investigated at ambient pressure. A dynamic method was used to determine the (solid-liquid) equilibrium phase diagrams in binary systems over a wide composition range and temperature range from T = 255.15 to 365.15 K up to the fusion temperature of ILs. The immiscibility gap with an upper critical solution temperature (UCST) was observed for each binary system under study. The influence of the alkane chain length of the substituent on the IL cation and of the sulfur compounds (the aromaticity of the solvent) was described. The experimental (solid + liquid) phase equilibrium dataset were successfully correlated using the well-known NRTL equation.


Subject(s)
Cations/chemistry , Heptanes/chemistry , Ionic Liquids/chemistry , Organic Chemicals/chemistry , Phase Transition , Quinolinium Compounds/chemistry , Sulfur Compounds/chemistry , Thermodynamics , Models, Theoretical , Solubility , Solvents/chemistry
4.
J Phys Chem B ; 122(23): 6188-6197, 2018 06 14.
Article in English | MEDLINE | ID: mdl-29763313

ABSTRACT

Ionic liquids (ILs) are important new solvents proposed for applications in different separation processes. Herein, an idea of possible use of high pressure in a general strategy of production of 2-phenylethanol (PEA) is discussed. In this work, we present the influence of pressure on the density in binary systems of {1-hexyl-1-methylpyrrolidynium bis{(trifluoromethyl)sulfonyl}imide, [HMPYR][NTf2], or 1-dodecyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide, [DoMIM][NTf2] + PEA} in a wide range of temperatures (298.15-348.15 K) and pressures (0.1-40 MPa). The densities at ambient and high pressures are measured to present the physicochemical properties of the ILs used in the process of separation of PEA from aqueous phase. The Tait equation was used for the correlation of density of one-component and two-component systems as a function of mole fraction, temperature, and pressure. The influence of pressure is not significant. These systems exhibit mainly negative molar excess volumes, VE. The solid-liquid phase equilibrium (SLE) of [DoMIM][NTf2] in PEA at atmospheric pressure was measured and compared to the SLE high-pressure results. Additionally, the ternary liquid-liquid phase equilibrium (LLE) at ambient pressure in the {[DoMIM][NTf2] (1) + PEA (2) + water (3)} at temperature T = 308.15 K was investigated. The solubility of water in the [DoMIM][NTf2] is quite high in comparison with that measured by us earlier for ILs ( x3 = 0.403) at T = 308.15 K, which results in not very successful average selectivity of extraction of PEA from the aqueous phase. The [DoMIM][NTf2] has shown strong interaction with PEA without the immiscibility region. The ternary system revealed Treybal's type phase equilibrium in which two partially miscible binaries ([DoMIM][NTf2] + water) and (PEA + water) exist. From the results of LLE in the ternary system, the selectivity and the solute distribution ratio of separation of water/PEA were calculated and compared to the results obtained for the ILs measured earlier by us. The popular NRTL model was used to correlate the experimental tie-lines in ternary LLE. These results may help in a new technological project of "in situ" extraction of PEA from aqueous phase during the biosynthesis.

5.
Eur J Pharm Sci ; 111: 270-277, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-28986197

ABSTRACT

Synthesis of three mefenamic acid (MEF) derivatives - ionic liquid compounds composed of MEF in an anionic form and ammonium cation (choline, MEF1), or {di(2-hydroxyethyl)dimethyl ammonium (MEF2)}, or {tri(2-hydroxyethyl)methyl ammonium compound (MEF3)} is presented. The basic thermal properties of pure compounds i.e. fusion temperatures, and the enthalpy of fusion of these compounds have been measured with differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The solubilities of MEF1, MEF2 and MEF3 using the dynamic method were measured at constant pH in a range of temperature from (290 to 370) K in three solvents: water, ethanol and 1-octanol. The experimental solubility data have been correlated by means of three commonly known GE equations: the Wilson, NRTL and UNIQUAC with the assumption that the systems studied here present simple eutectic behaviour. The activity coefficients of pharmaceuticals at saturated solutions in each binary mixture were calculated from the experimental data. The formation of MEF-ionic liquid compounds greatly increases the solubility in water in comparison with pure MEF or complexes with 2-hydroxypropyl-ß-cyclodextrin. The development of these compounds formulations will assist in medication taking into account oral solid or gel medicines.


Subject(s)
Alcohols/chemistry , Ammonium Compounds/chemistry , Ionic Liquids/chemistry , Mefenamic Acid/chemistry , Water/chemistry , Mefenamic Acid/analogs & derivatives , Models, Chemical , Molecular Structure , Solubility
6.
J Phys Chem B ; 121(32): 7689-7698, 2017 08 17.
Article in English | MEDLINE | ID: mdl-28723222

ABSTRACT

This study assessed the effect of ionic liquids (ILs) on extraction of 2-phenylethanol (PEA) from aqueous phase. It consists the synthesis of four new ILs, their physicochemical properties, and experimental solubility measurements in water as well as liquid-liquid phase equilibrium in ternary systems. ILs are an important new media for imaging and sensing applications because of their solvation property, thermal stability, and negligible vapor pressure. However, complex procedures and nonmiscibility with water are often required in PEA extraction. Herein, a facile and general strategy using four ILs as extraction media including the synthesis of new bis(fluorosulfonyl)imide-based ILs, 1-hexyl-methylmorpholinium bis(fluorosulfonyl)imide, [HMMOR][FSI], N-octylisoquinolinium bis(fluorosulfonyl)imide, [OiQuin][FSI], 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide, [BMPYR][FSI], and N-triethyl-N-octylammonium bis(fluorosulfonyl)imide, [N2228][FSI], were investigated. The thermal properties, density, viscosity, and surface tension of new ILs were measured. Calorimetric measurements (DSC) were used to determine the melting point and the enthalpy of melting as well as the glass transition temperature and heat capacity at glass transition of the ILs. The phase equilibrium in binary systems (IL + PEA, or water) and in ternary systems {IL (1) + PEA (2) + water (3)} at temperature T = 308.15 K and ambient pressure are reported. All systems present liquid-liquid equilibrium with the upper critical solution temperature (UCST). All ILs revealed complete miscibility with PEA. In all ternary systems immiscibility gap was observed, which classified measured systems as Treybal's type II. The two partially miscible binaries (IL + water) and (PEA + water) exist in these systems. The discussion contains the specific selectivity and the solute distribution ratio of separation for the used ILs. The commonly used NRTL model was used for the correlation of the experimental binary and ternary systems with acceptable root-mean-square deviation. The prediction of binary and ternary compositions was provided with acceptable deviations using COSMO RS. The data of ternary LLE show the possible use of [HMMOR][FSI] as a good entrainer for the separation of PEA from water using solvent extraction.

7.
J Phys Chem B ; 120(50): 12928-12936, 2016 12 22.
Article in English | MEDLINE | ID: mdl-27936736

ABSTRACT

Terpenes are an abundant and diverse class of chemicals having numerous applications in different areas of chemistry. Therefore, a detailed knowledge of physical and thermodynamic properties of terpenes and their mixtures with other compounds is highly desired. This paper reports both a thermodynamic study on solid-liquid equilibrium (SLE) phase diagrams in binary systems formed by (±)-camphene (a representative terpene) and one of the following solvents: n-decane, n-dodecane, 1-decanol, 1-dodecanol, phenylmethanol, 2-phenylethanol, 2-cyclohexylethanol. The observed trends in the measured SLE data are discussed in terms of structure (alkyl chain length, aromacity) of the solvent and molecular interactions. Modeling of the considered SLE phase diagrams with three well-established thermodynamic models, namely, modified UNIFAC (Dortmund), perturbed-chain statistical associating fluid theory (PC-SAFT) and conductor-like screening model for real solvents (COSMO-RS), is presented. A comparative analysis of their performance is given in terms of average absolute deviations between predicted and experimental SLE temperature.

8.
Crit Rev Oncol Hematol ; 97: 107-17, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26321372

ABSTRACT

Cancer metastasis causes most cancer-related deaths. Several model systems to study the complex and multi step process of metastasis exist, including in vitro systems, ex-vivo organ slices, Drosophila Melanogaster and zebrafish models and the use of the chorio allantoic membrane (CAM) of fertilized chicken eggs. These models are relatively easy and cheap but often lack the opportunity to study the complete metastasis cascade. More complex but also more expensive is the use of animal models including the more recently developed patient derived tumor xenografts (PDTX). In this review, we give an overview of the existing metastatic models, discuss the challenges of improving current models to enhance translation from the preclinical to the clinical setting and consider future perspectives.


Subject(s)
Disease Models, Animal , Neoplasms/pathology , Animals , Humans
9.
J Solution Chem ; 44(3-4): 382-394, 2015.
Article in English | MEDLINE | ID: mdl-25983354

ABSTRACT

In this work, the desulfurization ability of alkyl-piperidinium-based and phosphonium-based ionic liquids (ILs) for (thiophene or benzothiophene + heptane) mixtures are studied. With this aim, ternary liquid-liquid phase equilibrium data (LLE) have been obtained for mixtures of {IL (1) + thiophene, or benzothiophene (2) + heptane (3)} at T = 308.15 K and p = 101.33 kPa. For this study 1-pentyl-1-methylpiperidinium bis{(trifluoromethyl)sulfonyl}imide, [C1C5PIP][NTf2], and tributylethylphosphonium diethylphosphate, [P2,4,4,4][DEP], were used. The suitability of these ILs as solvents for extractive desulfurization has been evaluated in terms of the solute distribution ratio and selectivity. Immiscibility was observed in the binary liquid systems of (thiophene, or benzothiophene + heptane) with both ILs. One of the studied ILs, [C1C5PIP][NTf2], shows high distribution ratios and high selectivities for extraction of sulfur compounds. The data obtained have been correlated with the non-random two liquid NRTL model. The experimental tie-lines and the phase compositions in mole fractions in the ternary systems were calculated with an average root mean square deviation of 0.0052.

10.
Curr Pharm Des ; 21(17): 2276-83, 2015.
Article in English | MEDLINE | ID: mdl-25557636

ABSTRACT

Metastatic rectal cancer patients could benefit from novel therapeutic approaches. The signaling network formed by chemokines and their receptors can promote metastasis and resistance to current anticancer treatments. This study assessed the expression of chemokine receptor 4 (CXCR4) and its ligand CXCL12 immuhistochemically in stage IV rectal tumors. Paraffin-embedded primary tumor collected before and after local radiotherapy and systemic treatment with bevacizumab, oxaliplatin and capecitabine was analyzed. Receptor and ligand expression was assessed in the cytoplasm and nucleus of tumor, stromal and normal rectal crypt cells. Baseline expression of CXCR4 and CXCL12 was correlated with patients' pathologic response to treatment. At diagnosis (n=46), 89% of the rectal tumors expressed cytoplasmic CXCR4 and 81% CXCL12. Nuclear CXCR4 expression in tumor cells was present in 30% and nuclear CXCL12 expression in 35% of the tumors. After radiochemotherapy and administration of bevacizumab, nuclear CXCL12 expression was observed in 79% of residual tumors, as compared to 31% of the paired tumor samples expressing nuclear CXCL12 before treatment (P=0.001). There were no differences in CXCR4 or CXCL12 expression at baseline between the patients who had (n=9) and did not have (n=30) a pathologic complete response. Our results show that CXCR4 and CXCL12 are extensively expressed in primary rectal tumors of patients presenting with metastatic disease, while radiochemotherapy and bevacizumab further upregulate CXCL12 expression. These data indicate the importance of the CXCR4/CXCL12 axis in rectal tumor biology, and may suggest the CXCR4/CXCL12 receptor-ligand pair as a potential therapeutic target in metastatic rectal cancer.


Subject(s)
Chemokine CXCL12/biosynthesis , Neoadjuvant Therapy , Receptors, CXCR4/biosynthesis , Rectal Neoplasms/drug therapy , Rectal Neoplasms/metabolism , Rectal Neoplasms/radiotherapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols , Female , Humans , Immunohistochemistry , Male , Middle Aged , Neoplasm Staging , Rectal Neoplasms/pathology
11.
J Phys Chem B ; 119(2): 543-51, 2015 Jan 15.
Article in English | MEDLINE | ID: mdl-25513724

ABSTRACT

This work is concerned with thermodynamic properties of binary mixtures composed of 1-butyl-1-methylpyrrolidinium dicyanamide ionic liquid (IL) and the following molecular solvents: n-heptane, benzene, toluene, ethylbenzene, thiophene, 1-butanol, 1-hexanol, and 1-octanol. This is the very first time when experimental data on liquid-liquid equilibrium (LLE) phase diagrams and excess enthalpies of mixing (H(E)) for these systems are reported. An impact of the molecular solvent structure on LLE and H(E) is discussed. Furthermore, modeling of the properties under study is presented by using perturbed-chain statistical associating fluid theory (PC-SAFT). The equation of state is used in purely predictive and semipredictive mode. The latter one involves temperature-dependent binary corrections to combining rules employed in the PC-SAFT model determined on the basis of infinite dilution activity coefficients. The results shown indicate that such an approach can serve as an interesting modern thermodynamic tool for representation of thermodynamic data for complex ILs-based systems.

12.
Int J Mol Sci ; 15(12): 23909-23, 2014 Dec 22.
Article in English | MEDLINE | ID: mdl-25535080

ABSTRACT

In our study, poly(dl-lactide-co-glycolide) (PLGA) nanoparticles loaded with perphenazine (PPH) and chlorpromazine hydrochloride (CPZ-HCl) were formulated by emulsion solvent evaporation technique. The effect of various processing variables, including PLGA concentration, theoretical drug loading, poly(vinyl alcohol) (PVA) concentration and the power of sonication were assessed systematically to obtain higher encapsulation efficiency and to minimize the nanoparticles size. By the optimization formulation process, the nanoparticles were obtained in submicron size from 325.5 ± 32.4 to 374.3 ± 10.1 nm for nanoparticles loaded with PPH and CPZ-HCl, respectively. Nanoparticles observed by scanning electron microscopy (SEM) presented smooth surface and spherical shape. The encapsulation efficiency of nanoparticles loaded with PPH and CPZ-HCl were 83.9% and 71.0%, respectively. The drug loading were 51.1% and 39.4% for PPH and CPZ-HCl, respectively. Lyophilized nanoparticles with different PLGA concentration 0.8%, 1.3% and 1.6% (w/v) in formulation process were evaluated for in vitro release in phosphate buffered saline (pH = 7.4) by using dialysis bags. The release profile for both drugs have shown that the rate of PPH and CPZ-HCl release were dependent on a size and amount of drugs in the nanoparticles.


Subject(s)
Chlorpromazine/administration & dosage , Delayed-Action Preparations , Dopamine Antagonists/administration & dosage , Lactic Acid/chemistry , Nanoparticles/chemistry , Perphenazine/administration & dosage , Polyglycolic Acid/chemistry , Chemistry, Pharmaceutical , Chlorpromazine/chemistry , Dopamine Antagonists/chemistry , Hydrogen-Ion Concentration , Kinetics , Nanoparticles/ultrastructure , Particle Size , Perphenazine/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer
13.
J Solution Chem ; 43(11): 1929-1946, 2014.
Article in English | MEDLINE | ID: mdl-25484473

ABSTRACT

The effects of temperature and composition on the density and viscosity of pure benzothiophene and ionic liquid (IL), and those of the binary mixtures containing the IL 1-butyl-1-methylpyrrolidynium tricyanomethanide ([BMPYR][TCM] + benzothiophene), are reported at six temperatures (308.15, 318.15, 328.15, 338.15, 348.15 and 358.15) K and ambient pressure. The temperature dependences of the density and viscosity were represented by an empirical second-order polynomial and by the Vogel-Fucher-Tammann equation, respectively. The density and viscosity variations with compositions were described by polynomials. Excess molar volumes and viscosity deviations were calculated and correlated by Redlich-Kister polynomial expansions. The surface tensions of benzothiophene, pure IL and binary mixtures of ([BMPYR][TCM] + benzothiophene) were measured at atmospheric pressure at four temperatures (308.15, 318.15, 328.15 and 338.15) K. The surface tension deviations were calculated and correlated by a Redlich-Kister polynomial expansion. The temperature dependence of the interfacial tension was used to evaluate the surface entropy, the surface enthalpy, the critical temperature, the surface energy and the parachor for pure IL. These measurements have been provided to complete information of the influence of temperature and composition on physicochemical properties for the selected IL, which was chosen as a possible new entrainer in the separation of sulfur compounds from fuels. A qualitative analysis on these quantities in terms of molecular interactions is reported. The obtained results indicate that IL interactions with benzothiophene are strongly dependent on packing effects and hydrogen bonding of this IL with the polar solvent.

14.
J Phys Chem B ; 118(44): 12692-705, 2014 Nov 06.
Article in English | MEDLINE | ID: mdl-25317901

ABSTRACT

In the present work the excess enthalpies of butyltrimethylammonium bis(trifluoromethyl-sulfonyl)imide, [N1114][NTf2], with 1,2-propanediol, or 1,2-butanediol, or 2,3-butanediol have been measured at T = 298.15 K. Additionally, the density, ρ, and dynamic viscosity, η, for binary solutions containing ionic liquids (ILs) and alkanedioles, {butyltrimethylammonium bis(trifluoromethyl-sulfonyl)imide, [N1114][NTf2], + 1,2-propanediol, 1,2-butanediol, 2,3-butanediol} and {(2-hydroxyethyl)trimethylammonium bis(trifluoro-methylsulfonyl)imide, [N1112OH][NTf2], + 1,2-propanediol, 1,3-propanediol, 1,5-pentanediol}, at wide temperature and composition ranges at ambient pressure have been investigated. From experimental values of the density, ρ, and dynamic viscosity, η, the excess molar volumes, V(E), and dynamic viscosity deviations, Δη, were calculated and correlated using the Redlich-Kister polynomial equation. The temperature dependence of density and viscosity for the tested binary systems was described by an empirical second-order polynomial and by the Vogel-Fucher-Tammann equation, respectively. The variation of density and viscosity as a function of composition has been described by the polynomial correlations. Comparison of the experimental results for the binary mixtures tested in this work allows us to determine the influence of alkanediol carbon chain length, the position of the hydroxyl group in the alcohol, and the influence of the structure of the cation of the ionic liquid on the presented properties.

15.
Clin Exp Metastasis ; 31(7): 829-39, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25154297

ABSTRACT

Preclinical studies show that stroma affects sensitivity of prostate cancer cells via activation of the CXCR4/CXCL12 pathway. Here we studied the effect of CXCR4 inhibition combined with irradiation in prostate cancer cells. In an in vitro co-culture with stromal cells, the CXCR4 inhibitor AMD3100 sensitized prostate cancer cell lines PC3-Luc and LNCaP to irradiation (P = 0.04). Tumor growth and metastasis were evaluated in mice xenografted with luciferase-expressing PC3 cells that received 5 Gy irradiation weekly ± 3.5 mg/kg AMD3100 daily intraperitoneally. The irradiated xenografts showed higher CXCR4 (P = 0.006) and CXCL12 (P = 0.01) expression, compared to controls. AMD3100 sensitized the xenografts to irradiation at the fourth week of treatment (P = 0.02). However AMD3100 also mobilized tumor cells at days 14 and 21 (P < 0.0001), as shown by bioluminescent imaging. In conclusion, AMD3100 transiently enhances prostate cancer radiosensitivity, but induces cancer cell mobilization.


Subject(s)
Disease Models, Animal , Prostatic Neoplasms/pathology , Radiation Tolerance , Receptors, CXCR4/antagonists & inhibitors , Animals , Male , Mice , Receptors, CXCR4/physiology
16.
Phys Chem Chem Phys ; 16(23): 11417-25, 2014 Jun 21.
Article in English | MEDLINE | ID: mdl-24803282

ABSTRACT

In this paper we present the synthesis route and electrochemical properties of new class of ionic liquids (ILs) obtained from lithium derivate TDI (4,5-dicyano-2-(trifluoromethyl)imidazolium) anion. ILs synthesized by us were EMImTDI, PMImTDI and BMImTDI, i.e. TDI anion with 1-alkyl-3-methylimidazolium cations, where alkyl meant ethyl, propyl and butyl groups. TDI anion contains fewer fluorine atoms than LiPF6 and thanks to C-F instead of P-F bond, they are less prone to emit fluorine or hydrogen fluoride due to the rise in temperature. Use of IL results in non-flammability, which is making such electrolyte even safer for both application and environment. The thermal stability of synthesized compounds was tested by DSC and TGA and no signal of decomposition was observed up to 250 °C. The LiTDI salt was added to ILs to form complete electrolytes. The structures of tailored ILs with lithium salt were confirmed by X-ray diffraction patterns. The electrolytes showed excellent properties regarding their ionic conductivity (over 3 mS cm(-1) at room temperature after lithium salt addition), lithium cation transference number (over 0.1), low viscosity and broad electrochemical stability window. The ionic conductivity and viscosity measurements of pure ILs are reported for reference.

17.
J Chem Inf Model ; 54(5): 1311-24, 2014 May 27.
Article in English | MEDLINE | ID: mdl-24758717

ABSTRACT

A knowledge of various thermophysical (in particular transport) properties of ionic liquids (ILs) is crucial from the point of view of potential applications of these fluids in chemical and related industries. In this work, over 13 000 data points of temperature- and pressure-dependent viscosity of 1484 ILs were retrieved from more than 450 research papers published in the open literature in the last three decades. The data were critically revised and then used to develop and test a new model allowing in silico predictions of the viscosities of ILs on the basis of the chemical structures of their cations and anions. The model employs a two-layer feed-forward artificial neural network (FFANN) strategy to represent the relationship between the viscosity and the input variables: temperature, pressure, and group contributions (GCs). In total, the resulting GC-FFANN model employs 242 GC-type molecular descriptors that are capable of accurately representing the viscosity behavior of ILs composed of 901 distinct ions. The neural network training, validation, and testing processes, involving 90, 5, and 5% of the whole data pool, respectively, gave mean square errors of 0.0334, 0.0595, and 0.0603 log units, corresponding to squared correlation coefficients of 0.986, 0.973, and 0.972 and overall relative deviations at the level of 11.1, 13.8, and 14.7%, respectively. The results calculated in this work were shown be more accurate than those obtained with the best current GC model for viscosity of ILs described in the literature.


Subject(s)
Databases, Chemical , Ionic Liquids/chemistry , Neural Networks, Computer , Models, Chemical , Pressure , Viscosity
18.
Int J Mol Sci ; 14(8): 16638-55, 2013 Aug 13.
Article in English | MEDLINE | ID: mdl-23945559

ABSTRACT

The solubility of ß-cyclodextrin (ß-CD) in ionic liquids (ILs) and the activity coefficients at infinite dilution (γ13(∞)) of more than 20 solutes (alkanes, aromatic hydrocarbons, alcohols) were measured in four chosen ionic liquids, their mixtures with ß-CD, and in the ß-CD at high temperatures from 338 to 398 K using the inverse gas chromatography. The intermolecular interactions, inclusion complexes and the possible increasing of the solubility of ß-CD in water using the IL are presented. The solubility of ß-CD in ten chosen hydrophobic ILs at the temperature T = 423 K was detected. The solid-liquid phase diagrams (SLE) of {IL (1) + ß-CD (2)} binary systems at the high mole fraction of the IL were measured for three systems (1-ethyl-3-methylimidazolium chloride, [EMIM][Cl], 1-ethyl-3-methylimidazolium bromide, [EMIM][Br]; and for 1-butyl-3-methylimidazolium chloride, [BMIM][Cl]). The eutectic points were determined at the high IL concentration for all binary systems. The intermolecular interaction and the possibility of inclusion complexes of the IL and/or solvents with ß-CD were discussed. The infrared spectroscopy, IR was used for the description of the intermolecular interactions in the (ß-CD + IL) systems. It was shown via the activity coefficients at infinite dilution results that the inclusion complexes are dependent on the temperature. The addition of ß-CD to the IL does not improve the selectivity of the separation of the aliphatics from aromatics.


Subject(s)
Ionic Liquids/chemistry , beta-Cyclodextrins/chemistry , Hydrophobic and Hydrophilic Interactions , Imidazoles/chemistry , Solubility
19.
Eur J Pharm Biopharm ; 85(1): 151-7, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23958326

ABSTRACT

In the field of drug delivery systems, microparticles made of polymeric matrix appear as an attractive approach. The in vitro release kinetic profile is crucial information when developing new particulate formulations. These data are essential for batch to batch comparison, quality control as well as for anticipation of in vivo behavior to select the best formulation to go further in preclinical investigations. The methods available present common drawbacks such as the time- and compound-consumption that does not fit with formulation screening requirements in early development stages. In this study, a new microscale high throughput screening (HTS) method has been developed to investigate drug release kinetic from piroxicam-loaded polylactic acid (PLA) and polylactic-co-glycolic acid (PLGA) microparticles. The method is a sample- and separation-based method where separation is performed by filtration using 96-well micro filter plates. 96 experiments can therefore be performed on one plate in one time in a fully automated way and with a very low sample and particle consumption. The influence of different parameters controlling release profiles was also investigated using this technique. The HTS method gave the same release profile than the standard dialysis method. Shaking, particle concentration, and the nature of the release medium were found to be of influence. The HTS method appears as a reliable method to evaluate drug release from particles with smaller standard deviation and less consumption of material.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Lactic Acid/chemistry , Piroxicam/chemistry , Polyesters/chemistry , Polyglycolic Acid/chemistry , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Automation, Laboratory , Chemical Phenomena , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemistry , Drug Compounding , Filtration , High-Throughput Screening Assays , Kinetics , Microchemistry , Microscopy, Electron, Scanning , Microspheres , Particle Size , Piroxicam/administration & dosage , Polylactic Acid-Polyglycolic Acid Copolymer , Quality Control , Reproducibility of Results , Solubility , Surface Properties
20.
J Phys Chem B ; 117(23): 7034-46, 2013 Jun 13.
Article in English | MEDLINE | ID: mdl-23683321

ABSTRACT

Experimental and theoretical studies on thermodynamic properties of three ionic liquids based on dicyanamide anion (namely, 1-butyl-3-methylimidazolium dicyanamide, 1-butyl-1-methylpyrrolidinium dicyanamide, and 1-butyl-1-methylpiperidinium dicyanamide) and their binary mixtures with sugar alcohols (D-sorbitol and xylitol) were conducted in order to assess the applicability of the salts ionic liquids for dissolution of those biomass-related materials. Density and dynamic viscosity (at ambient pressure) of pure ionic liquids are reported in the temperature range from T = 293.15 to 363.15 K. Solid-liquid equilibrium phase diagrams in binary systems {sugar alcohol + ionic liquid} were measured with dynamic method up to the fusion temperature of sugar alcohol. The impact of the chemical structure of both the ionic liquid and sugar alcohol were established and discussed. For the very first time, the experimental solubility data were reproduced and analyzed in terms of equation of state rooted in statistical mechanics. For this purpose, perturbed-chain statistical associating fluid theory (PC-SAFT) was employed. In particular, new molecular schemes for the ionic liquids, D-sorbitol, and xylitol were proposed, and then the pure chemicals were parametrized by using available density and vapor pressure data. The model allowed accurate correlation of pure fluid properties for both ionic liquids and sugar alcohols, when the association term is taken into account. The results of solid-liquid equilibria modeling were also satisfactory. However, one or two adjustable binary corrections to the adopted combining rules were required to be adjusted in order to accurately capture the phase behavior. It was shown that a consistent thermodynamic description of extremely complex systems can be achieved by using relatively simple (but physically grounded) theoretical tools and molecular schemes.


Subject(s)
Ionic Liquids/chemistry , Solvents/chemistry , Sorbitol/chemistry , Xylitol/chemistry , Biomass , Green Chemistry Technology , Models, Molecular , Solubility , Temperature , Thermodynamics , Viscosity
SELECTION OF CITATIONS
SEARCH DETAIL
...