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Cationic polymers

Weiping Cao, Margarita Mishina, Samuel Amoah, Wadzanai P Mboko, Caitlin Bohannon, James McCoy, Suresh K Mittal, Shivaprakash Gangappa, Suryaprakash Sambhara
Avian influenza virus infection is a serious public health threat and preventive vaccination is the most cost-effective public health intervention strategy. Unfortunately, currently available unadjuvanted avian influenza vaccines are poorly immunogenic and alternative vaccine formulations and delivery strategies are in urgent need to reduce the high risk of avian influenza pandemics. Cationic polymers have been widely used as vectors for gene delivery in vitro and in vivo. In this study, we formulated H5N1 influenza vaccines with GenJet™ or in vivo-jetPEI® , and showed that these formulations significantly enhanced the immunogenicity of H5N1 vaccines and conferred protective immunity in a mouse model...
November 2018: Drug Delivery
Amirhossein Mafi, Srinivas Abbina, Manu Thomas Kalathottukaren, James H Morrissey, Charles Haynes, Jayachandran N Kizhakkedathu, Jim Pfaendtner, Keng C Chou
Inorganic polyphosphate (polyP) released by human platelets has recently been shown to activate blood clotting and identified as a potential target for the development of novel antithrombotics. Recent studies have shown that polymers with cationic binding groups (CBGs) inhibit polyP and attenuate thrombosis. However, a good molecular-level understanding of the binding mechanism is lacking for further drug development. While molecular dynamics (MD) simulation can provide molecule-level information, the time scale required to simulate these large biomacromolecules makes classical MD simulation impractical...
March 14, 2018: Biomacromolecules
Mayte Martinez-Martinez, Guillermo Rodriguez-Berna, Isabel Gonzalez Alvarez, M Jesus Hernandez, Avelino Corma, Marival Bermejo, Virginia Merino, Marta Gonzalez-Alvarez
In this work, 6-phosphogluconic trisodium salt (6-PG-Na+) is introduced as a new aqueous and non-toxic crosslinker agent to obtain ionic hydrogels. Here, it is shown the formation of hydrogels based on chitosan crosslinked with 6-PG-Na+. This formulation is obtained by ionic interaction of cationic groups of polymer with anionic groups of crosslinker. These hydrogels are non-toxic, do not cause dermal irritation, are easy to extend and have an adequate adhesion force to be applied as polymeric film over the skin...
March 14, 2018: Biomacromolecules
Jesse Gatten McDaniel, Chang Yun Son, Arun Yethiraj
Room temperature ionic liquids composed of organic anions bis(trifluoromethanesulfonyl)imide (TFSI), bis(fluorosulfonyl)imide (FSI), and trifluoromethanesulfonate (OTf) exhibit interesting physical properties and are important for many electrochemical applications. TFSI and FSI form ``hydrophobic'' ionic liquids, immiscible with water but miscible with many organic solvents and polymers; for computer simulation studies, it is thus essential to develop force fields for these anions that are transferable among this wide variety of chemical environments...
March 14, 2018: Journal of Physical Chemistry. B
Konstantin S Rodygin, Alexander S Bogachenkov, Valentine P Ananikov
We developed a simple and efficient strategy to access N -vinyl secondary amines of various naturally occurring materials using readily available solid acetylene reagents (calcium carbide, KF, and KOH). Pyrrole, pyrazole, indoles, carbazoles, and diarylamines were successfully vinylated in good yields. Cross-linked and linear polymers were synthesized from N -vinyl carbazoles through free radical and cationic polymerization. Post-modification of olanzapine (an antipsychotic drug substance) was successfully performed...
March 13, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Tsukuru Masuda, Naohiko Shimada, Atsushi Maruyama
Membrane active peptides (MAPs) have potential applications in drug delivery systems and as antimicrobials. We previously showed that a cationic comb-type copolymer, poly(allylamine)-graft-dextran (PAA-g-Dex), forms a soluble inter-polyelectrolyte complex with an anionic MAP, the E5 peptide, resulting in significant enhancement of the membrane disruption activity of E5. In this study, we designed a novel comb-type cationic copolymer composed of a PAA main chain and thermo-responsive poly(N-isopropylacrylamide) graft chains (PAA-g-PNIPAAm)...
March 12, 2018: Biomacromolecules
Yohei Ishida, Akihiro Morita, Tomoharu Tokunaga, Tetsu Yonezawa
We herein present the preparation of short, bulky cationic thiolate (thiocholine) protected fluorescent Au nanoclusters via sputter deposition over a liquid polymer matrix. The obtained Au nanoclusters showed near-infrared fluorescence and had an average core diameter of 1.7 ± 0.6 nm, which is too large compared with that of the reported fluorescent Au nanoclusters prepared via chemical means. We revealed the mechanism of formation of this unique material using single-particle electron microscopy, optical measurements, X-ray photoelectron spectroscopy (XPS), and high-performance liquid chromatography fractionations...
March 12, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Yannick P Borguet, Sarosh Khan, Amandine Noel, Sean P Gunsten, Steven L Brody, Mahmoud Elsabahy, Karen L Wooley
To expand the range of functional polymer materials to include fully hydrolytically degradable systems that bear bioinspired phosphorus-containing linkages both along the backbone and as cationic side chain moieties for packaging and delivery of nucleic acids, phosphonium-functionalized polyphosphoester- block-poly(l-lactide) copolymers of various compositions were synthesized, fully characterized, and their self-assembly into nanoparticles were studied. First, an alkyne-functionalized polyphosphoester- block-poly(l-lactide) copolymer was synthesized via a one pot sequential ring opening polymerization of an alkyne-functionalized phospholane monomer, followed by the addition of l-lactide to grow the second block...
March 11, 2018: Biomacromolecules
Guocheng Zhu, Junfei Liu, Yongning Bian
Dissolved organic nitrogen (DON) is an important component of aquatic environment of which amount impacts water quality. Thus, removal of DON has attracted wide attention. At present, it is difficult for common coagulation to remove DON from the aquatic environment. The cationic polymers can help to improve the removal efficiency of DON to some extent, but the underlying mechanism of the ascension is not clear. In order to grasp its removal behavior and further improve the removal efficiency of DON in the future, we evaluated the effect of a hybridized coagulant of polyacrylamide with iron-based coagulant on removal of aquatic DON...
March 10, 2018: Environmental Science and Pollution Research International
Akhila Jose, Mrudula Surendran, Sajid Fazal, Bindhu-Paul Prasanth, Deepthy Menon
This work reports the potential of iron quantum clusters (FeQCs) as a hyperthermia agent for cancer, by testing its in-vitro response to shortwave (MHz range), radiofrequency (RF) waves non-invasively. Stable, fluorescent FeQCs of size ∼1 nm prepared by facile aqueous chemistry from endogenous protein haemoglobin were found to give a high thermal response, with a ΔT ∼50 °C at concentrationsas low as165 μg/mL. The as-prepared nanoclusters purified by lyophilization as well as dialysis showed a concentration, power and time-dependent RF response, with the lyophilized FeQCs exhibiting pronounced heating effects...
February 27, 2018: Colloids and Surfaces. B, Biointerfaces
Brynn R Olden, Yilong Cheng, Jonathan L Yu, Suzie H Pun
The clinical success of chimeric antigen receptor (CAR) T cell immunotherapy in treating multiple blood cancers has created a need for efficient methods of ex vivo gene delivery to primary human T cells for cell engineering. Here, we synthesize and evaluate a panel of cationic polymers for gene delivery to both cultured and primary human T cells. We show that a subset of comb- and sunflower-shaped pHEMA-g-pDMAEMA polymers can mediate transfection with efficiencies up to 50% in the Jurkat human T cell line with minimal concomitant toxicity (>90% viability)...
March 5, 2018: Journal of Controlled Release: Official Journal of the Controlled Release Society
Huijun Li, Yu Jun Tan, Sijun Liu, Lin Li
A novel strategy to improve the adhesion between printed layers of 3D printed constructs is developed by exploiting the interaction between two oppositely charged hydrogels. Three anionic hydrogels (alginate, xanthan, kappa-carrageenan (Kca)) and three cationic hydrogels (chitosan, gelatin, gelatin methacrylate (GelMA)) are chosen in order to find the optimal combination of two oppositely charged hydrogels for the best 3D printability with strong interface bonding. Rheological properties and printability of the hydrogels, as well as structural integrity of printed constructs in cell culture medium, are studied as functions of polymer concentration and combination of hydrogels...
March 8, 2018: ACS Applied Materials & Interfaces
Abdul-Hackam Ranneh, Hiroyasu Takemoto, Shunya Sakuma, Aziz Awaad, Takahiro Nomoto, Yuki Mochida, Makoto Matsui, Keishiro Tomoda, Mitsuru Naito, Nobuhiro Nishiyama
Polyzwitterions have been employed as coating polymers for biomaterials, in order to install antifouling property on the surface. Herein, we demonstrated that fine-tuning of the betaine structure builds a molecular program to switch the antifouling property to be interactive with anionic tissue constituents in response to tumorous pH gradient. Ethylenediamine moiety in the carboxybetaine enabled stepwise protonation and initiated the di-protonation process around tumorous pH 6.5; thus, the net charge of the developed polyzwitterion (PGlu(DET-Car)) was neutral at pH 7...
March 7, 2018: Angewandte Chemie
Yi-Hsuan Lin, Julie D Forman-Kay, Hue Sun Chan
Liquid-liquid phase separation and related condensation processes of intrinsically disordered proteins (IDPs), proteins with intrinsically disordered regions and nucleic acids underpin various condensed-liquid droplets or gel-like assemblies in the cellular environment. Collectively referred to as condensates, these bodies provide spatial/temporal compartmentalization, often serving as hubs for regulated biomolecular interactions. Examples include certain extracellular materials, transcription complexes, and membraneless organelles such as germ and stress granules and the nucleolus...
March 6, 2018: Biochemistry
Danila Merino, Andrea Yamila Mansilla, Claudia A Casalongué, Vera Alejandra Alvarez
Clay based nanocomposites (nano-clays) are interesting systems to hold a wide type of active substances with a wide field of industrial applications. Bentonite-Chitosan nano-clay was obtained via cationic exchange of natural bentonite (Bent) with an aqueous solution of chitosan (CS). Their physicochemical and morphological properties were discussed under the light of Fourier Transform Infrared Spectroscopy, X-ray diffraction, Thermogravimetric analysis and Scanning electron microscopy. Bent-CS characterization indicated that CS was intercalated in a 10% w/w...
March 6, 2018: Journal of Agricultural and Food Chemistry
Qiang Yan, Wei Sang
Cationic polymerizations have long been industrialized; however, stimulus-regulated cationic polymerization remains to be developed. Here we report an electrochemically controlled living cationic polymerization for the first time. In the presence of external potential and organic-based electrocatalyst, a series of monomers can be polymerized under a cationic chain transfer mechanism. The resulting polymers exhibit well-defined molecular mass, narrow dispersity and good chain-end fidelity. Controlling the external potential to switch the electrocatalyst between its oxidized and reduced states can achieve the "ON/OFF" polymerization...
March 6, 2018: Angewandte Chemie
Baizhu Chen, Lei Yu, Zhibo Li, Chi Wu
Mixing cationic polymer chains with anionic DNA chains in solution results in the polymer/DNA complexes (also known as polyplexes). We recently confirmed that it is those non-complexed cationic chains free in the mixture that promote the gene transfection, leading to a hypothesis: free cationic chains adsorbed on various anionic membranes interfere with the signal protein interaction, disrupt the inter-vesicular fusion and block the endolysosome pathway so that the plasmid DNA (pDNA) chains have a higher chance to enter the nucleus...
March 5, 2018: Biomacromolecules
Tristan Neumann, Magdalena Ceglarska, Luzia S Germann, Michał Rams, Robert E Dinnebier, Stefan Suckert, Inke Jess, Christian Näther
Reaction of Ni(NCS)2 with 4-aminopyridine in different solvents leads to the formation of compounds with the compositions Ni(NCS)2 (4-aminopyridine)4 (1), Ni(NCS)2 (4-aminopyridine)2 (H2 O)2 (2), [Ni(NCS)2 (4-aminopyridine)3 (MeCN)]·MeCN (3), and [Ni(NCS)2 (4-aminopyridine)2 ]n (5-LT). Compounds 1, 2, and 3 form discrete complexes, with octahedral metal coordination. In 5-LT the Ni cations are linked by single thiocyanate anions into chains, which are further connected into layers by half of the 4-aminopyridine coligands...
March 5, 2018: Inorganic Chemistry
Wen Cui, Ruyu Wang, Xi Shu, Yu Fan, Yang Liu, Yongdong Jin, Chuanqin Xia, Chao Huang
The interaction between the uranyl cation, (UO2 )2+ , and organic species is of interest due to the potential applications of the resulting compounds with regard to nuclear waste disposal and nuclear fuel reprocessing. The hydrothermal reaction of various uranyl compounds with flexible zwitterionic 1,1'-[1,4-phenylenebis(methylene)]bis(pyridin-1-ium-4-carboxylate) dihydrochloride (Bpmb·2HCl) in deionized water containing drops of H2 SO4 resulted in the formation of a novel two-dimensional uranyl coordination polymer, namely poly[tetraoxido{μ2 -1,1'-[1,4-phenylenebis(methylene)]bis(pyridin-1-ium-4-carboxylate)}di-μ3 -sulfato-diuranium(VI)], [(UO2 )2 (SO4 )2 (C20 H16 N2 O4 )]n , (1)...
March 1, 2018: Acta Crystallographica. Section C, Structural Chemistry
Peng Cheng Li, Kou Lin Zhang
Multifunctional 2-amino-5-sulfobenzoic acid (H2 afsb) can exhibit a variety of roles during the construction of supramolecular coordination polymers. The pendant carboxylic acid, sulfonic acid and amino groups could not only play a role in directing bonding but could also have the potential to act as hydrogen-bond donors and acceptors, resulting in extended high-dimensional supramolecular networks. Two new CuII coordination compounds, namely catena-poly[[[diaquacopper(II)]-μ-1,6-bis(1H-1,2,4-triazol-1-yl)hexane-κ2 N4 :N4' ] bis(3-amino-4-carboxybenzenesulfonate) dihydrate], {[Cu(C10 H16 N6 )2 (H2 O)2 ](C7 H6 NO5 S)2 ·2H2 O}n or {[Cu(bth)2 (H2 O)2 ](Hafsb)2 ·2H2 O}n , (1), and bis(μ-2-amino-5-sulfonatobenzoato-κ2 O1 :O1' )bis{μ-1,2-bis[(1H-imidazol-1-yl)methyl]benzene-κ2 N3 :N3' }bis[aquacopper(II)] trihydrate, [Cu2 (C7 H5 NO5 S)2 (C14 H14 N4 )2 (H2 O)2 ]·3H2 O or [Cu2 (afsb)2 (obix)2 (H2 O)2 ]·3H2 O, (2), have been obtained through the assembly between H2 afsb and the CuII ion in the presence of the flexible N-donor ligands 1,6-bis(1H-1,2,4-triazol-1-yl)hexane (bth) and 1,2-bis[(1H-1,2,4-triazol-1-yl)methyl]benzene (obix), respectively...
March 1, 2018: Acta Crystallographica. Section C, Structural Chemistry
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