33529-02-1Relevant articles and documents
Imidazolium-based zwitterionic surfactants: Characterization of normal and reverse micelles and stabilization of nanoparticles
Souza, Franciane D.,Souza, Bruno S.,Tondo, Daniel W.,Leopoldino, Elder C.,Fiedler, Haidi D.,Nome, Faruk
, p. 3587 - 3595 (2015)
This paper presents the physicochemical properties of micellar aggregates formed from a series of zwitterionic surfactants of the type 3-(1-alkyl-3-imidazolio)propane-sulfonate (ImS3-n), with n = 10, 12, 14, and 16. The ImS3-n dipolar ionic surfactants represent a versatile class of dipolar ionic compounds, which form normal and reverse micelles. Furthermore, they are able to stabilize nanoparticles in water and in organic media. Aqueous solubility is too low at room temperature to allow characterization of micellar aggregates but increases with addition of salts, allowing determination of aggregation number and cmc. As expected, these parameters depend on the length of the alkyl chain, and cmc values follow Klevens equation. In the presence of NaClO4, all ImS3-n micelles become anionoid by incorporating ClO4- on the micellar interface. A special feature of these surfactants is the ability to form reverse micelles and solubilize copious amounts of saline solutions in chloroform. 1H NMR and infrared spectroscopic evidence showed that the maximum water to surfactant molar ratio w0 achievable depends on the concentration and type of salt dissolved. Reverse micelles of the ImS3-n surfactants can be used to stabilize metallic nanoparticles, whose size may be tuned by the amount of water dissolved.
Ordered, microphase-separated, noncharged-charged diblock copolymers via the sequential ATRP of styrene and styrenic imidazolium monomers
Shi, Zhangxing,Newell, Brian S.,Bailey, Travis S.,Gin, Douglas L.
, p. 6664 - 6671 (2014)
A series of imidazolium-based noncharged-charged diblock copolymers (1) was synthesized by the direct, sequential ATRP of styrene and styrenic imidazolium bis(trifluoromethyl)sulfonamide monomers with methyl, n-butyl, and n-decyl side-chains. Small-angle X-ray scattering studies on initial examples of 1 with a total of 50 repeat units and styrene:imidazolium-styrene repeat unit ratios of 25:25, 20:30, and 15:35 showed that their ability to form ordered nanostructures (i.e., sphere and cylinder phases) in their neat states depends on both the block ratio and the length of the alkyl side-chain on the imidazolium monomer. To our knowledge, the synthesis of imidazolium-based BCPs that form ordered, phase-separated nanostructures via direct ATRP of immiscible co-monomers is unprecedented.
Synthesis of a novel alkylimidazolium iodide containing an amide group for electrolyte of dye-sensitized solar cells
Jeon, Seung-Hwan,Priya, A.R. Sathiya,Kang, Eun-Ji,Kim, Kang-Jin
, p. 5652 - 5658 (2010)
A novel alkylimidazolium iodide containing an amide group, 1-(2-hexanamidoethyl)-3-methylimidazol-3-ium iodide (amido-ImI), was synthesized to act as the quasi-solid-state electrolyte of dye-sensitized solar cells (DSSCs). The DSSC with the amido-ImI electrolyte exhibited short-circuit photocurrent density (Jsc) and overall energy conversion efficiency (η) that were improved by 7.2% and 10.2%, respectively, compared to those obtained with the cell containing 1-hexyl-2,3-dimethylimidazolium iodide, a commonly used liquid electrolyte, at 100mWcm-2. Furthermore, the stability of the DSSC was enhanced by the presence of amido-ImI.
Influence of dlutaraldehyde cross-linking modes on the recyclability of immobilized lipase b from candida antarctica for transesterification of soy bean oil
Modenez, Iago A.,Sastre, Diego E.,Moares, Fernando C.,Marques Netto, Caterina G.C.
, (2018)
Lipase B from Candida antarctica (CAL-B) is largely employed as a biocatalyst for hydrolysis, esterification, and transesterification reactions. CAL-B is a good model enzyme to study factors affecting the enzymatic structure, activity and/or stability after an immobilization process. In this study, we analyzed the immobilization of CAL-B enzyme on different magnetic nanoparticles, synthesized by the coprecipitation method inside inverse micelles made of zwitterionic surfactants, with distinct carbon chain length: 4 (ImS4), 10 (ImS10) and 18 (ImS18) carbons. Magnetic nanoparticles ImS4 and ImS10 were shown to cross-link to CAL-B enzyme via a Michael-type addition, whereas particles with ImS18 were bond via pyridine formation after glutaraldehyde cross-coupling. Interestingly, the Michael-type cross-linking generated less stable immobilized CAL-B, revealing the influence of a cross-linking mode on the resulting biocatalyst behavior. Curiously, a direct correlation between nanoparticle agglomerate sizes and CAL-B enzyme reuse stability was observed. Moreover, free CAL-B enzyme was not able to catalyze transesterification due to the high methanol concentration; however, the immobilized CAL-B enzyme reached yields from 79.7 to 90% at the same conditions. In addition, the transesterification of lipids isolated from oleaginous yeasts achieved 89% yield, which confirmed the potential of immobilized CAL-B enzyme in microbial production of biodiesel.
Crystallographic and spectroscopic analysis of 9,10-bis-alkyl imidazolium anthracene hexatungstate supramolecular complexes
Annapareddy, Gayatri,Mubeena, Shaik,N, Meghana,Sarma, Monima
, (2021)
This article describes the ionic and supramolecular association of bis-dialkyl imidazolium anthracene dications with hexametalate cluster anions. In the relevant compounds, the length of the alkyl chain was varied to observe its effect on the crystal packing. Despite the endothermicity in the crystals due to structural incompatibility between planar anthracene and spherical polyoxometalate ion, packing stability is attained by coulombic interaction together with the supramolecular interactions between the components. The nature of supramolecular interactions depends on the number of carbon atoms in the alkyl chain in the organic counterparts of the crystals which ultimately modifies the packing pattern.
A Remarkable Fluorescence Quenching Based Amplification in ATP Detection through Signal Transduction in Self-Assembled Multivalent Aggregates
Biswas, Rakesh,Naskar, Sumit,Ghosh, Surya,Das, Mousumi,Banerjee, Supratim
supporting information, p. 13595 - 13600 (2020/10/06)
Signal transduction is essential for the survival of living organisms, because it allows them to respond to the changes in external environments. In artificial systems, signal transduction has been exploited for the highly sensitive detection of analytes. Herein, a remarkable signal transduction, upon ATP binding, in the multivalent fibrillar nanoaggregates of anthracene conjugated imidazolium receptors is reported. The aggregates of one particular amphiphilic receptor sensed ATP in high pm concentrations with one ATP molecule essentially quenching the emission of thousands of receptors. A cooperative merging of the multivalent binding and signal transduction led to this superquenching and translated to an outstanding enhancement of more than a millionfold in the sensitivity of ATP detection by the nanoaggregates; in comparison to the “molecular” imidazolium receptors. Furthermore, an exceptional selectivity to ATP over other nucleotides was demonstrated.
Inhibition of bacterial growth and galactosyltransferase activity of WbwC by α, ω-bis(3-alkyl-1H-imidazolium)alkane salts: Effect of varying carbon content
Brockhausen, Inka,Kocev, Alexander,Kong, Xianqi,Melamed, Jacob,Szarek, Walter A.,Vlahakis, Jason Z.,Wang, Shuo,Xu, Yaozu
, (2020/04/21)
A series of compounds was designed and synthesized having two imidazolium rings separated by a polymethylene spacer and having alkyl substituents on each of the imidazolium rings. The compounds were assayed for their effects on the activity of galactosyltransferase WbwC, and also on the growth of Gram-negative and Gram-positive bacteria, as well as human cells. The inhibition observed on enzyme activities and cell growth was dependent on the total number of carbons in the spacer and the alkyl substituents on the imidazolium rings. These readily synthesized, achiral compounds have potential as antimicrobial and antiseptic agents.
Synthesis and Antibacterial Evaluation of Bis-thiazolium, Bis-imidazolium, and Bis-triazolium Derivatives
Thomas, Beno?t,Duval, Rapha?l E.,Fontanay, Stéphane,Varbanov, Mihayl,Boisbrun, Michel
supporting information, p. 1232 - 1237 (2019/06/13)
Given the worldwide spread of bacterial drug resistance, there is an urgent need to develop new compounds that exhibit potent antibacterial activity and that are unimpaired by this phenomenon. Quaternary ammonium compounds have been used for many years as disinfectants, but recent advances have shown that polycationic derivatives exhibit much stronger activity and are less prone to bacterial resistance than commonly used monocationic compounds. In this sense, we prepared three series of new bis-cationic compounds: bis-thiazoliums, bis-imidazoliums, and bis-1,2,4-triazoliums. If some compounds of the first series showed fair antibacterial activity, most of those belonging to the two other series were highly potent, with minimum inhibitory concentrations close to 1 μg mL?1. Some of them also exhibited low toxicity toward eukaryotic MRC-5 lung fibroblasts, and we showed that this toxicity is clearly correlated with clogP. Finally, four selected compounds were found to exhibit a clear bactericidal effect.
Novel alkylimidazolium ionic liquids as an antibacterial alternative to pathogens of the skin and soft tissue infections
Doria, Oscar Forero,Castro, Ricardo,Gutierrez, Margarita,Valenzuela, Diego Gonzalez,Santos, Leonardo,Ramirez, David,Guzman, Luis
, (2018/09/26)
Keeping in mind the concept of green chemistry, this research aims to synthesize and characterize new ionic liquids (ILs) derived from N-cinnamyl imidazole with different sizes of alkyl chains (1, 6, 8, and 10 carbon atoms), and evaluate their antibacterial activity against Skin and soft tissue infections (SSTIs) causative bacteria. The antibacterial screening was carried out by agar well diffusion and the Minimum Inhibitory Concentration (MIC) and Half Maximum Inhibitory Concentration (IC50) of the different ILs were determined by microdilution in broth, also Molecular dynamics simulations were performed to study the interaction mechanism between ILs and membranes. The MIC value in Gram-positive bacteria showed that as the hydrocarbon chain increases, the MIC value decreases with a dose-dependent effect. Furthermore, Gram-negative bacteria showed high MIC values, which were also evidenced in the antibacterial screening. The molecular dynamics showed an incorporation of the ILs with the longer chain (10 C), corresponding to a passive diffusion towards the membrane surface, for its part, the ILs with the shorter chain due to its lack of hydrophobicity was not incorporated into the bilayer. Finally, the new ILs synthesized could be an alternative for the treatment of Gram-positive bacteria causative of SSTIs.
A planar anthracene–imidazolium/anthracene–benzimidazolium cation system in a spherical polyoxometalate matrix: Synthesis, crystallography and spectroscopy
Chatterjee, Tanmay,Kumar, N. Tanmaya,Das, Samar K.
, p. 68 - 83 (2017/03/01)
A series of ion–pair compounds, comprising of Lindqvist type isopolyanions viz., [Mo6O19]2?and [W6O19]2?as the counter anions and anthracene–imidazolium/anthracene–benzimidazolium as counter cations, have been described. Structures of the isolated stoichiometric solids have been unambiguously determined by single crystal X-ray diffraction analysis. In spite of the structural incompatibility between anthracene (planar) and the present polyoxometalate anions (spherical), coulombic and several intermolecular weak interactions, e.g. C–H?O, C–H?π, π–π, etc. compensate the destabilization energy raised due to presence of the structurally mis-matched components in the respective crystal lattices. Single-crystal- as well as powder X-ray-diffraction (PXRD) analyses reveal iso-structural relationship between the hexamolybdates- and hexatungstates-associated ion pair compounds. Conformational variation has been observed in the crystal structures containing benzyl benzimidazolium counter cations. Diffuse reflectance electronic absorption spectral studies are performed to understand the relatively intense color of the title compounds in their solid states in comparison to their respective solution states.
