25308-80-9Relevant academic research and scientific papers
Hierarchically nanostructured polyisobutylene-based ionic liquids
Zare, Parvin,Stojanovic, Anja,Herbst, Florian,Akbarzadeh, Johanna,Peterlik, Herwig,Binder, Wolfgang H.
, p. 2074 - 2084 (2012)
A new type of highly temperature stable ionic liquid (IL) with strongly temperature dependent nanostructures is reported. The molecular design relies on the use of a liquid polymer with an ionic liquid headgroup, introducing liquid properties by both the polymeric and the ionic liquid (IL) headgroup. The IL polymers (poly(isobutylene)s) 3a-3c (PIB-ILs) were prepared by a combination of living carbocationic polymerization (LCCP) and subsequent "click" chemistry for attachment of methylimidazolium (3a), pyrrolidinium (3b), and triethylammonium cations (3c). All three investigated PIB-ILs exhibited pronounced nanostructural organization at room temperature depending strongly on the nature of the anchored cation. Whereas the morphology of the imidazolium-based PIB-IL 3a shows high thermal stability up to the decomposition temperature, order-order (OOT) and lattice disorder-order transitions (LDOT) characteristic for common ionomers could be observed in the case of pyrrolidinium 3b and ammonium-based 3c PIB-ILs. Control of flow behavior as well as adjustable relaxation times from the liquid to the viscoelastic regime can be adjusted by choice of the appropriate IL headgroup.
High yield production of high molecular weight poly(ethylene glycol)/α-cyclodextrin polyrotaxanes by aqueous one-pot approach
Sun, Haiyan,Han, Jin,Gao, Chao
, p. 2884 - 2889 (2012)
An easy, one-pot, high-yield preparation of high molecular weight polyrotaxanes (PRs) from poly(ethylene glycol) (PEG) and α-cyclodextrin (α-CD) by click chemistry is presented with novel water soluble and clickable end-capping agents containing quaternary ammonium and propargyl groups. The threading numbers of α-CD on the PEG chain were investigated by means of 1H NMR spectroscopy and gel permeation chromatography (GPC). When Mn of the PEG axis is 35 kDa, the yield is up to 614 mg per 100 mg PEG axis and the average number of α-CDs on each PEG axis is 193. Wide-angle X-ray diffraction (WAXD) revealed that PRs form a column-type crystalline structure. The prepared PR possesses terminal alkyne groups which can connect with functional molecules to make the PR more useful. As a typical example, fluorescent rhodamine B has been successfully installed on the PR terminals.
Construction of Silver Clusters Capped by Zwitterionic Ethynide Ligands
Shen, Yang-Lin,Jin, Jun-Ling,Fang, Jun-Jie,Liu, Zheng,Shi, Jian-Lin,Xie, Yun-Peng,Lu, Xing
, p. 6276 - 6282 (2021)
A zwitterionic ligand 3-(triethylammonio)propyne (TAP) has been employed to construct nine silver ethynide compounds for the first time. Single-crystal X-ray analyses reveal that compounds 1 and 2 are silver ethynide assemblies based on the Ag3 subunits and clusters 3-8 are small discrete clusters of Ag3, Ag6, Ag8, and Ag12, respectively, ligated by the bulky TAP ligand with different auxiliary ligands. In addition, upon acquiring the tripod-like tBuPO32-, a unprecedented 80 nuclei silver ethynide cluster was isolated and determined to be [(CF3CO2)5@Ag80(TAP)14(tBuPO3)16(CF3CO2)24]19+ by crystallography and thermogravimetric analysis. The C1 symmetry of Ag80 was deconstructed to be two [Ag40(TAP)7(tBuPO3)8(CF3CO2)12]12+ secondary building subunits arranged in a cross way, with five CF3CO2- trapped in the center. These results highlight that the elaborate selection of ethynide ligands is of great importance in the synthesis of novel silver ethynide clusters.
Synthesis, surface properties and bioactivity of novel 4-Substituted 1,2,3-Triazole quaternary ammonium surfactants
Mechken, Karima Amel,Menouar, Mohammed,Belkhodja, Moulay,Saidi-Besbes, Salima
, (2021/07/09)
Series of novel 1,2,3-triazole based quaternary ammonium surfactants with different hydrophobic chain length and head group substituents were synthetized and characterized. Their surface properties and aggregation behavior were discussed on the basis of tensiometry and conductimetry measurements by using several parameters, including critical micelle concentration (CMC), surface tension at the cmc (γcmc), adsorption efficiency (pC20), effectiveness of surface tension reduction (Πcmc), minimum surface area occupied by a molecule (Amin) at the air ? water interface and standard Gibbs free energy of micellization ΔGMic0. These heterocyclic surfactants exhibit much lower CMC values as compared with those reported for conventional alkyltriethyl ammoniums and alkylbenzyldiethyl ammonium salts. Their micelles formation and surface adsorption in aqueous media can be tuned out through a suitable choice of the substituent attached to the polar head. Triethyl ammonium (CnTzTEA] and diethylbenzyl ammonium surfactants (CnTzBz) showed improved micellization behavior than tetradecyl diethyl ammonium (CnTzC14) homologous. The in vitro antimicrobial activity of the surfactants against B. subtilis, P. aerugenosa and A.niger strains was also investigated. CnTzBz series possessing benzyl chain showed better activity against all the tested microorganisms with minimum inhibitory concentration ranging from 6 to 57 μmol/L.
α-Tocopherol-based cationic amphiphiles with a novel pH sensitive hybrid linker for gene delivery
Muripiti, Venkanna,Rachamalla, Hari Krishnareddy,Banerjee, Rajkumar,Patri, Srilakshmi V.
, p. 2932 - 2946 (2018/05/03)
Endosomal escape is one of the barriers for the efficient liposomal gene delivery. To address this and based on earlier encouraging results using tocopherol cationic lipids, we elaborated chemical modifications on tocopherol cationic lipids by introducing a novel hybrid pH sensitive linker "ether-β-hydroxy-triazole" between tocopherol, the anchoring moiety and the basic tris(2-hydroxy ethyl)quaternary ammonium head group (Lp2). As control lipids we designed two lipids (Lp1 and Lp3), one is with only the ether-β-hydroxy linker in between α-tocopherol and quaternary tris(2-hydroxyethyl)ammonium (Lp1) and the other is with the same novel hybrid linker i.e. "ether-β-hydroxy-triazole" between the α-tocopherol linked and quaternary tris-ethyl ammonium head group (Lp3). Liposomes were formulated with a combination of a well-known co-lipid, 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and biophysical characteristics such as DNA binding, hydrodynamic diameters and global surface charges for liposomes and lipoplexes of respective lipids were evaluated. Cell viability assay and in vitro transfection studies were carried out in NIH3 T3, B16F10, HEK-293, and HepG2 cell lines. In vitro transfection data for the liposomes of lipids (Lp1, Lp2 and Lp3) revealed that the Lp2 lipid with a novel hybrid pH sensitive linker showed superior transfection efficiency when compared with the remaining two analogues. More importantly, Lp2 has shown a similar pattern of transfection efficiency in HepG2 and HEK-293 cell lines when compared with commercially available Lipofectamine 3000.
