Triethanolammonium Cations Research Articles

In Vitro Antiproliferative, Antibacterial, and Anti-Angiogenic Studies of Triethanolamine-Based Salts

The triethanolammonium (TEA) cation associated with the anion cyclopropanecarboxylate, mercaptoacetate, trichloroacetate, and 4-dodecylbenzenesulfonate led to the formation of TEA-based salts. The antibacterial activity of the TEA salts was examined against some bacteria and the obtained results were used to calculate minimal inhibitory concentrations (MICs) values. Additionally, the antiproliferative activities of TEA salts were examined in vitro on breast cancer cell line. Furthermore, in vitro scratch assay was performed by HUVECs (human vascular endothelial cell line) to assess the anti-angiogenic effect of these salts. These compounds did not dramatically differentiate the cell viability of cancer cells. On the other hand, it was demonstrated that TEA salts blocked human endothelial cell migration slightly. Therefore, these compounds were determined to have a limited ability to inhibit angiogenesis.

Assembling Lipoic Acid and Nanoclay into Nacre-Mimetic Nanocomposites

A facile strategy to obtain nacre-mimetic nanocomposite materials is presented. The proposed economically feasible and environmentally friendly process consists in fusing dynamic poly(lipoic acid) and montmorillonite (MTM) via a water evaporation method. Lipoic acid (LA), a naturally occurring molecule, can readily undergo thermal-, UV-, or (water) evaporation-induced dynamic ring-opening polymerization. This monomer has been equipped with various organic and inorganic counter cations, altering the physical properties of both the obtained poly(lipoate)s and the resulting nacre-like nanocomposites. The mechanical performance of the nanocomposites can be accordingly tuned from rigid and brittle to soft and ductile. Importantly, the composites containing triethanolammonium cations show enhanced ductility with an elongation at break up to around 16% when compared to other reported nacre-mimetic nanocomposites with similar MTM content (elongation at break usually below 10%). Moreover, the influence of MTM content on the mechanical properties of the nanocomposites is elucidated. Furthermore, the dynamic nature of the poly(lipoate)s and supramolecular architecture within the composites enables water-assisted self-healing of superficial scratches, as evaluated by optical microscopy, and closed-loop recycling for materials with up to 70 wt % MTM. Finally, the nanocomposites were found to exhibit flame retardancy.

Cytotoxicity of protic ionic liquids towards the HaCat cell line derived from human skin

In this work we have investigated the toxicity of 10 PILs, consisting of ethyl-, ethanol-, diethanol- and triethanolammonium cations paired with nitrate, formate, acetate and glycolate anions. Their toxicity was quantified by the EC50 values of each of these PILs towards HaCat cells, which are derived from human skin cells. Additional salts and solvents were used for comparison including DMSO, choline chloride, potassium nitrate, sodium acetate and ethanol to distinguish if the toxicity changes were due to ionicity, short chain amphiphilic behaviour, or specific ion effects. The toxicity followed the general trend of choline chloride < acetate containing PILs < DMSO < sodium acetate < ethanol < nitrate containing PILs or salt. Ethanolammonium acetate and ethylammonium acetate were identified as having the lowest toxicities of the PILs, being slightly more toxic than choline chloride or DMSO. Overall the toxicity was found to be highly dependent on the cation and anion combination, with the anion having a stronger affect. It was evident that the PILs can be tailored to vary their toxicities, and this is expected to be dependent on which cell lines are used.

Quantum Chemical Modeling of the Structure and H Bonding in Triethanolammonium-Based Protic Ionic Liquids with Sulfonic Acids.

The results of electronic structure calculations based on density functional theory (DFT) for protic ionic liquids (PILs) consisting of triethanolammonium cation paired with anion of different sulfonic acids are reported. The influence of the anion nature on the structure and interactions in the ion pairs that are formed in these PILs is discussed in detail. Multiple H-bonding interactions exist between the protons in the NH/OH groups of the cation and different oxygen atoms of the acid anion in the ion pairs. The quantum theory of "atoms in molecules" has been used to estimate the individual contributions of each hydrogen bond to the stability of the ion pair. The hydrogen-bonding interactions in the ion pairs vary in their strength ranging from weak to moderately strong. In addition to these hydrogen bonds, there are other dispersion and electrostatic-dominant interactions that play an important role in the overall stability of PILs and their physicochemical properties. Aided by results from our previous DFT studies of triethanolammonium class of PILs with inorganic anions, these new data allow us to gain an improved understanding of the structure-property relationships in the studied ionic liquids. Close to linear correlation, in particular, has been found between the melting points and the binding energies of the cation and anion in the ion pairs.

FTIR Spectroscopic Study of the Secondary Structure of Globular Proteins in Aqueous Protic Ionic Liquids.

Protein misfolding is a detrimental effect which can lead to the inactivation of enzymes, aggregation, and the formation of insoluble protein fibrils called Amyloids. Consequently, it is important to understand the mechanism of protein folding, and under which conditions it can be avoided or mitigated. Ionic liquids (ILs) have previously been shown as capable of increasing or decreasing protein stability, depending on the specific IL, IL concentration and which protein. However, a greater range of IL-proteins need to be systematically explored to enable the development of structure-property relationships. In this work, the secondary structure of four proteins, lysozyme, trypsin, β-lactoglobulin and α-amylase, were studied in aqueous solutions of 10 protic ionic liquids (PILs) with 0–50 mol% PIL present. The PILs consisted of ethyl-, ethanol-, diethanol- and triethanolammonium cations paired with nitrate, formate, acetate or glycolate anions. The secondary structure was obtained using ATR-FTIR spectroscopy. It was found that lysozyme and trypsin retained its secondary structure, consistent with a native folded state, for many of the aqueous IL solutions which contained a formate or nitrate anion at the most dilute concentrations. In contrast, α-amylase and β-lactoglobulin generally had poor stability and solubility in the IL solutions. This may be due to the isoelectric point of α-amylase and β-lactoglobulin being closer to the pH of the solvents. All four proteins were insoluble in ethyl-, ethanol- and diethanolammonium acetate, though α-amylase and trypsin retained their secondary structure in up to 20 and 30 mol% of triethanolammonium acetate, respectively. It was evident that the protein stability varied substantially depending on the protein-IL combination, and the IL concentration in water. Overall, the findings indicated that some ions and some ILs were in general better for protein solubility and stability than others, such as acetate leading to poor solubility, and EAN and EAF generally leading to better protein stability than the other PILs. This study of four proteins in 10 aqueous PILs clearly showed that there are many complexities in their interactions and no clear general trend, despite the similarities between the PIL structures. This highlights the need for more and larger studies to enable the selection and optimization of PIL solvents used with biomolecules.

The Nature of the Interactions in Triethanolammonium-Based Ionic Liquids. A Quantum Chemical Study.

Structural features and interionic interactions play a crucial role in determining the overall stability of ionic liquids and their physicochemical properties. Therefore, we performed high-level quantum-chemical study of different cation-anion pairs representing the building units of protic ionic liquids based on triethanolammonium cation and anions of sulfuric, nitric, phosphoric, and phosphorus acids to provide essential insight into these phenomena at the molecular level. It was shown that every structure is stabilized through multiple H bonds between the protons in the N-H and O-H groups of the cation and different oxygen atoms of the anion acid. Using atoms in molecules topological parameters and natural bond orbital analysis, we determined the nature and strength of these interactions. Our calculations suggest that the N-H group of the cation has more proton donor-like character than the O-H group that makes the N-H···O hydrogen bonds stronger. A close relation between the binding energies of these ion pairs and experimental melting points was established: the smaller the absolute value of the binding energy between ions, the lower is the melting point.

Absorption Behavior of Acid Gases in Protic Ionic Liquid/Alkanolamine Binary Mixtures

Herein, we studied the absorption of H2S and CO2 by alkanolamine–protic ionic liquids binary mixtures based on 2-hydroxyethylammonium (MEA) or triethanolammonium cations and residues of 2-hydroxy-5-sulfobenzoic acid or pyridine-3-carboxylic acid at various temperatures and partial gases pressures. It was found that absorbents based on the 2-hydroxyethylammonium cation, performed high absorption properties toward the H2S. The solubility of hydrogen sulfide, characterized by the Henry’s Law constant, in MEA-based binary mixtures had the values comparable to the commercially available ionic liquids. The results of thermal desorption analysis demonstrated that the capture of acid gases in MEA-based absorbents occurred at two stages: through the dissolution in MEA component and in protic ionic liquid.

Ionic liquids based on triethanolammonium salts of dicarboxylic acids (oxalic, malonic, succinic). Crystal structure and cation-anion interaction

The series of ionic liquids based on triethanolammonium salts of dicarboxylic acids (oxalic, malonic and succinic) was synthesized, characterized by IR and H1, C13 NMR spectroscopy, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Their structure was determined by single-crystal X-ray diffraction. It was found that triethanolammonium [(HOCH2CH2)3NH]+ cations in salts of oxalic (1), malonic (2) and succinic acids (3) containing monoanions [OOC(CH2)nCOOH]− (n = 0–2) have the endo conformation and the ammonium proton (Ham) resides inside the “lampshade” formed by three CH2CH2OH branches connected with nitrogen atom. The asymmetric cell of the second modification of the succinic acid salt (4) includes two triethanolammonium cations and a succinate dianion [(HOCH2CH2)3NH]2+[OOC(CH2)2COO]2 −. In this salt (4) one CH2CH2OH branch of the triethanolammonium cation is rotated around the NC bond (endo-exo conformation) and forms infinite TEA chains. This pattern was firstly found in organic salts of TEA. The obtained results show that different structures of triethanolammonium cations in the salts of dicarboxylic acids have significant influence on the cation-anion interaction.

Protic alkanolammonium ionic liquids based on triethanolammonium salts of carboxylic acids

A configuration of the triethanolammonium cation is determined by the X-ray diffraction method, and cation-anion interactions in its salts with oxalic, succinic, and salicylic acids are investigated. The reaction of the triethanolammonium salts with silver nitrate is studied, and the structure of the reaction product is determined.

Development and Characterization of Amine-Clay Hybrid Adsorbents for CO&lt;sub&gt;2&lt;/sub&gt; Capture

The present work aims at a better understanding of the influences of the intercalated mono-, di- and triethanolamines on the characteristics and CO2 adsorption ability of sodium form of bentonite (Na-bentonite). The results revealed that the molar mass of intercalated amines significantly influenced the structural and surface properties as well as the CO2 adsorption capacity of Na-bentonite. In this respect, a stepwise increase in the d-spacing of Na-bentonite with the molar mass of amine was recorded by XRD technique. However, an inverse effect of the molar mass of amine on the surface area was confirmed by BET method. CO2 adsorption experiments on amine-bentonite hybrid adsorbents showed that the CO2 adsorption capacity inversly related to the molar mass of amine at 25 ͦC and 101 kPa. Accordingly, Na-bentonite modified by monoethanolammonium cations adsorbed as high as 0.475 mmol CO2/g compared to 0.148 and 0.087 mmol CO2/g for that one treated with di- and triethanolammonium cations, respectively.

Effects of Intercalated Mono-, Di- and Triethanolammonium Cations on the Structural and Surface Characteristics of Sodium Form of Bentonite

The present study investigates the effects of intercalation process of protonated primary, secondary and tertiary amines on structural and surface characteristics of sodium form of bentonite clay. For this purpose, sodium form of bentonite clay was prepared and then exchanged with mono-, di-and triethanolammonium cations via intercalation mechanism into the interlayer space of the clay. The prepared samples were characterized by XRD and BET techniques. An increase in the d-spacing of bentonite clay with the molar mass of amines was observed in their x-ray diffractograms, following the order of: triethanolamine &gt; diethanolamine &gt; monoethanolamine. The BET results showed a gradual decrease in the BET surface area with the increase in the molar mass of amines used. Based on the results obtained, it can be concluded that the molar mass of amines has significant effects on structural and surface properties of bentonite clay.

Carbon Dioxide Retention on Bentonite Clay Adsorbents Modified by Mono-, Di- and Triethanolamine Compounds

A series of organic-inorganic hybrids were developed via intercalation process of primary, secondary and tertiary ammonium cations into different alkali and alkaline earth and transition metal cation forms of bentonite clay to be used as adsorbent materials for CO2capture under ambient temperature and slightly high pressure. The effect of the molar mass of amines on the structural characteristics, surface properties and CO2loading capacity of bentonite clay were investigated by X-ray diffraction, Brunauer-Emmett-Teller method and Magnetic Suspension Balance equipment, respectively. X-ray diffraction results revealed that the basal spacing of bentonite clay after modification with amines was increased with the molar mass of amine used, while BET results showed an inverse effect of the molar mass of amines on the surface area of the synthesized materials. The CO2loading capacity of the examined samples revealed that bentonite clay modified with monoethanolammonium cations retained higher CO2amount compared to those modified with di-and triethanolammonium cations. CO2adsorption isotherms on MEA+-Mg-MMT were conducted at 298, 323 and 348 K and different pressures. A decrease in CO2uptake with increasing temperature was observed, suggesting the exothermic nature of the adsorption process.

Sulfonic Acid Group Functionalized Ionic Liquid Catalyzed Hydrolysis of Cellulose in Water: Structure Activity Relationships

Catalytic activities of eight sulfonic acid group functionalized ionic liquids in water were compared for the hydrolysis of Sigmacell cellulose (DP ~ 450) in the 150-180°C temperature range by measuring total reducing sugar (TRS) and glucose produced. The catalytic activity of acidic ionic liquids with different cation types decreases in the order imidazolium > pyridinium > triethanol ammonium cation. Among the sulfonic acid group functionalized imidazolium ionic liquids, the catalysts which contain a single imidazolium ion and a flexible linker between sulfonic acid group and the imidazolium ionic liquid core structure are the most active catalysts.

Effects of exchanged ammonium cations on structure characteristics and CO2 adsorption capacities of bentonite clay

Different alkali and alkaline earth cation forms of bentonite clay were exchanged with protonated mono-, di- and triethanolamine compounds, to study the effect of the exchanged ammonium cations on the structure characteristics, thermal behavior, surface properties and CO2 adsorption capacities of bentonite clay. The revolution of the interlayer structure characteristics, thermal properties, the specific surface area and elemental analysis were characterized by XRD, FTIR, TGA, BET and CHNS techniques respectively, while the CO2 adsorption capacities were gravimetrically measured by using magnetic suspension balance (MSB) equipment. It was found that the intercalation of ammonium cations into the interlayer space of bentonite clay induced a step change in its basal spacing, depending on their molar mass and the interlayer molecular arrangement. The presence of the characteristic IR peaks of amine compounds in the spectra of bentonite clay adsorbents modified by amines was qualitatively supported by the incorporation of ammonium cations in the interlayer space of bentonite, while the presence of C, H and N elements using CHNS technique was quantitatively confirmed by the intercalation process of amine compounds. It was also found that the molar mass of amines has an inverse effect on the amount of the adsorbed water (intensity), its desorption temperature (position) and the specific surface area of the synthesized materials. The CO2 adsorption capacities on all the studied bentonite clay adsorbents modified by amines were found to increase between 2.68 and 3.15mmol/g, compared to 0.93mmol/g for untreated bentonite at the studied temperature and pressure. As expected, bentonite clay modified with di- and triethanolammonium cations showed lower CO2 adsorption capacities than that treated with monoethanolammonium cations, due to their low specific surface area.

Thermal properties of different transition metal forms of montmorillonite intercalated with mono-, di-, and triethanolammonium compounds

In the present study, different transition metal forms of montmorillonite have been intercalated with mono-, di-, and triethanolammonium cations via d coordination mechanism to investigate their thermal behavior, structural characteristics, surface properties, and elemental composition using TG, XRD, BET, and CHNS techniques. Thermogravimetric analysis showed two thermal transition steps for transition metal-exchanged montmorillonites, which attributed to desorption of the physically adsorbed water and hydrated water, and dehydroxylation of the structural water; whereas for ammonium-montmorillonite complexes, the TG curves showed three thermal transition steps which attributed to desorption of the adsorbed water and dehydration, decomposition of the ammonium cations in the interlayer space of montmorillonite, and the dehydroxylation of the structural water. The thermal analysis of ammonium-montmorillonites affirmed that the molar mass of amine compounds used affects both desorption temperature (position) and the amount of the adsorbed water (intensity). XRD results revealed that the molar mass of amine used has linear relation with the basal spacings of the corresponding ammonium-montmorillonites, indicating structural changes. BET results showed that the molar mass of amines has an inverse effect on the surface area of the studied samples. CHNS analysis for the studied samples quantitatively confirmed the intercalation of ammonium cations into the interlayer space of montmorillonite.

Thermogravimetric analysis of different molar mass ammonium cations intercalated different cationic forms of montmorillonite

Different cationic forms of montmorillonite, mainly K-, Na-, Ca- and Mg-montmorillonites were intercalated in this study via ion exchange process with mono-, di-, and triethanolammonium cations. The developed samples were characterized by TG, XRD, and CHNS techniques. Thermogravimetric study of ammonium-montmorillonites shows three thermal transition steps, which are attributable to the volatilization of the physically adsorbed water and dehydration, followed by the decomposition of the intercalated ammonium cations and dehydroxylation of the structural water of the modified clay, respectively, while untreated and cationic forms of montmorillonite showed only two decomposition steps. The type of ammonium cation has affected both desorption temperature (Position) and the amount of the adsorbed water (intensity). XRD results show a stepwise change in the crystallographic spacings of montmorillonite with the molar mass of ammonium cation, reflecting a change in the structure of the clay. CHNS data confirm the intercalation of ammonium cations into the interlayer space of montmorillonite and corroborate the effect of the molar mass of ammonium cation on the amount adsorbed by the clay.

PH-Dependence of the aqueous electrochemistry of the two-electron reduced α-[Mo18O54(SO3)] sulfite Dawson-like polyoxometalate anion derived from its triethanolammonium salt

The electrochemistry of the Dawson-like sulfite polyoxometalate anion alpha-[Mo18O54(SO3)2]6-, derived from the TEAH6{alpha-[Mo18O54(SO3)2]} salt (TEAH+ is the triethanolammonium cation; pKa=7.8), has been investigated in aqueous media using cyclic and rotated disk voltammetry at glassy carbon electrodes and bulk electrolysis, with a focus on the pH-dependence for oxidation to alpha-[Mo18O54(SO3)2]4-. In buffered media at pH>or=4, the cyclic voltammetric response for alpha-[Mo18O54(SO3)2]6- reveals two partially resolved one-electron oxidation processes corresponding to the sequential generation of alpha-[Mo18O54(SO3)2]5- and alpha-[Mo18O54(SO3)2]4-. At lower pH, using electrolytes containing sulfuric acid, the two waves coalesce but the individual apparent E0' reversible formal potential values for the two processes can be extracted down to pH 2 by assuming that reversible protonation accompanies fast electron transfer. The results for 2<or=pH<or=8 are well described by the double-square scheme mechanism: [FORMULAS: SEE TEXT] where A, B and C correspond to species alpha-[Mo18O54(SO3)2]4-, alpha-[Mo18O54(SO3)2]5- and alpha-[Mo18O54(SO3)2]6- respectively. The following thermodynamic values could be deduced: E=-0.009 V vs. Fc+/Fc; E=-0.125 V vs. Fc+/Fc and KC=1.5x10(-5) M; values for KA, KB, E and E could not be determined. Protonated alpha-[HMo18O54(SO3)2]5-, deduced to be the major species present at pH<4, is highly stable in aqueous media. In contrast, alpha-[Mo18O54(SO3)2]6-, which is dominant at higher pH values, slowly decomposes. Data considered in the context of acid-base properties of both the TEAH+ cation and alpha-[HMo18O54(SO3)2]5- anion imply that the TEAH+ cation is important in the isolation of (TEAH)6{alpha-[Mo18O54(SO3)2]}. Cyclic and rotating disk electrode voltammetries demonstrate that at least 8 electrons also can be easily added to the [Mo18O54(SO3)2]4- framework in acidic media. The existence of the electron transfer series alpha-[Mo18O54(SO3)2]4-/5-/6-/7-/8- was confirmed by cyclic voltammetric studies of water insoluble [Pn4N]4{alpha-[Mo18O54(SO3)2]} adhered to a glassy carbon electrode in contact with an aqueous 0.1 M Et4NCl electrolyte.

A New Decavanadate Salt Incorporating Both Inorganic and Organic Cations.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Crystal structure of triethanolammonium bis(1-hydroxyethane-1,1-diphosphonato)diaquazincate pentahydrate, [(OHCH2CH2)3NH][Zn(H2O)2(H2.5 L)2] ⋅ 5H2O

The crystal structure of [(HOCH2CH2)3NH][Zn(H2O)2(H2.5L)2] ⋅ 5H2O, where H4L is 1-hydroxyethane-1,1-diphosphonic acid, was determined by X-ray diffraction. The anionic complex has a cis-octahedral structure. The zinc atom is coordinated by four O atoms of two bidentate chelate H2.5L1.5− ligands and two O atoms of water molecules. The Zn-O(L) bond lengths range between 2.050 and 2.175 A, and the Zn-O(H2O) bond lengths are 2.105 and 2.133 A. The anionic complexes, triethanolammonium cations, and molecules of crystallization water are interlinked by an extensive network of hydrogen bonds. The crystallographic data for isostructural complexes of cobalt and nickel are given.

Chloroantimonate(III), V. Darstellung und Kristallstruktur des Triethanolammoniuin-tetrachloroantimonats [(C2H4OH)3NH]SbCl4 / Chloroantimonates(III), V. Preparation and Crystal Structure of Triethanolammonium Tetrachloroantimonate [(C2H4OH)3NH]SbCl4

Triethanolammonium tetrachloroantimonate was synthesized and investigated by X-ray diffrac­tion analysis. The structure consists of SbCl3 molecules, chloride ions and triethanolammonium cations. The SbCl3 molecules and the cations form adducts by a bridging O-atom at 274.3 pm. The Sb-Cl distances within the SbCl3 molecule are 239.2, 240.3 and 245.3 pm, whereas the distances from the Sb atom th the Cl- ion are 290.2 and 332.1 pm.