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Cationic polymers

Lu Su, Richen Li, Sarosh Khan, Ryan Clanton, Fuwu Zhang, Yen-Nan Lin, Yue Song, Hai Wang, Jingwei Fan, Soleil Hernandez, Andrew S Butters, Gamal Akabani, Ronan MacLoughlin, Justin Smolen, Karen L Wooley
Although nanomedicines have been pursued for nearly 20 years, fundamental chemical strategies that seek to optimize both the drug and drug carrier together in a concerted effort remain uncommon yet may be powerful. In this work, two block polymers and one dimeric prodrug molecule were designed to be coassembled into degradable, functional nanocarriers, where the chemistry of each component was defined to accomplish important tasks. The result is a poly(ethylene glycol) (PEG)-protected redox-responsive dimeric paclitaxel (diPTX)-loaded cationic poly(d-glucose carbonate) micelle (diPTX@CPGC)...
January 19, 2018: Journal of the American Chemical Society
Xu Zhen, Chen Xie, Yuyan Jiang, Xiangzhao Ai, Bengang Xing, Kanyi Pu
Nanomedicines have shown success in cancer therapy, but the pharmacological actions of most nanomedicine are often nonspecific to cancer cells because of utilization of the therapeutic agents that induce cell apoptosis from inner organelles. We herein report the development of semiconducting photothermal nanoagonists that can remotely and specifically initiate the apoptosis of cancer cells from cell membrane. The organic nanoagonists comprise semiconducting polymer nanoparticles (SPNs) and capsaicin (Cap) as the photothermally-responsive nanocarrier and the agonist for activation of transient receptor potential cation channel subfamily V member 1 (TRPV1), respectively...
January 17, 2018: Nano Letters
Mahmoud H Abu Elella, Riham R Mohamed, Marwa M Abdel-Aziz, Magdy W Sabaa
The present study is imported to solve two critical problems we face in our daily life which are microbial pollution and colon cancer. One pot green synthesis of a water soluble polyelectrolyte complex (PEC) between cationic polysaccharide as N,N,N-trimethyl chitosan chloride (TMC) and anionic polymer as poly (acrylic acid) (PAA) in presence of silver nanoparticles to yield (TMC/PAA/Ag) nanocomposites with different Ag weight ratios. Structure of TMC, PAA and TMC/PAA (PEC) were proved via different analysis tools...
January 12, 2018: International Journal of Biological Macromolecules
Danyang Li, Amir S Sharili, John Connelly, Julien E Gautrot
The high density of polymer brushes confers to these coatings unique physico-chemical properties, in particular for the regulation of biomolecular interaction and the design of highly selective coatings for biosensors and protein patterning. Here we show that high density poly(dimethylaminoethyl methacrylate) cationic polymer brushes enable the stable uptake of high levels of oligonucleotides. This is proposed to result from the high degree of crowding and associated increase in entropic driving force for the binding of polyelectrolytes such as nucleic acid molecules...
January 16, 2018: Biomacromolecules
Xiaozhen Lu, Hongxia Jia, Xiaohua Yan, Jingsha Wang, Yucong Wang, Chenghui Liu
A simple and homogeneous histone assay is developed based on histone-induced DNA compressing coupled with cationic conjugated polymer (CCP)-mediated fluorescence resonance energy transfer (FRET). In this strategy, the CCP serves as the FRET donor and SYBR Green I (SG), which can strongly fluoresce not at its free state but after intercalated into the double stranded calf thymus DNA (dsDNA), serves as the acceptor of FRET. In the absence of histone, the dsDNA-SG and CCP combine with each other through electrostatic interaction and the strong FRET from CCP to SG occurs due to the overlapping between the fluorescent emitting spectrum of the CCP and the absorption spectrum of SG...
April 1, 2018: Talanta
(no author information available yet)
Hyperkalaemia is a potentially life-threatening condition, in which there is an abnormally high concentration of potassium ions in the blood.1,2 Cation-exchange resins (e.g. calcium or sodium polystyrene sulfonate) that bind potassium in the gastrointestinal tract to increase faecal elimination have been used as part of the management of hyperkalaemia but they have some serious adverse effects, including potentially fatal gastrointestinal necrosis.3,4 Patiromer (▼Veltassa - Vifor Fresenius) is a cation-exchange polymer that is licensed for the treatment of hyperkalaemia in adults and, unlike other exchange resins, its licence is not restricted to people with anuria, severe oliguria or those requiring or undergoing dialysis...
January 2018: Drug and Therapeutics Bulletin
Chi Zhang, Jinkai Ji, Xiaoyan Shi, Xiaoyu Zheng, Xuewei Wang, Fude Feng
Water-soluble conjugated polymers (WCPs) have prospective applications in the field of bioimaging, disease diagnosis and therapy. However, the use of WCPs with controllability and regio-regularity for bioapplications have scarcely been reported. In this work, we synthesized polythiophenes containing ester side chains (P3ET) via Kumada catalyst-transfer polycondensation (KCTP) and confirmed a quasi-"living" chain-growth mechanism. In addition, we obtained cationic regioregular polythiophenes by aminolysis of P3ET with varied chain lengths, and studied DNA binding capability and gene delivery performance...
January 11, 2018: ACS Applied Materials & Interfaces
Guanjun Chang, Li Yang, Junxiao Yang, Mark P Stoykovich, Deng Xu, Jiaxi Cui, Dapeng Wang
Supramolecular chemistry has provided versatile and affordable solutions for the design of intelligent soft materials, but it cannot be applied in stiff materials. This paper describes a new concept for the design of high-performance supramolecular thermosets by using the noncovalent cation-π interaction as cross-linking. These supramolecular thermosets are a class of infusible and insoluble stiff polymers having excellent mechanical properties even at temperatures exceeding 300 °C. The cation-π interaction can be locally and reversibly installed and removed by aqueous treatments at high or low pH, respectively...
January 5, 2018: Advanced Materials
Monika Farys, Daniel Gibson, Alan Lewis, Will Lewis, Richard Kucia-Tran
Monoclonal antibodies of the IgG2 and IgG4 isotype were found to exhibit an increased propensity for displaying two-peak elution profiles during cation exchange chromatography. In some cases, this two-peak elution profile also resulted in the formation of non-reversible mAb aggregates. Comparison of IgG1, IgG2 and IgG4 molecules with the same variable region reveals that the two-peak behaviour is predominantly mediated by the constant region and most likely the lower CH1, hinge and upper CH2 regions of the mAb...
January 8, 2018: Biotechnology and Bioengineering
Jeffrey R Vieregg, Michael Lueckheide, Amanda Brittany Marciel, Lorraine Leon, Alex J Bologna, Josean Reyes Rivera, Matthew V Tirrell
When oppositely-charged polymers are mixed, counterion release drives phase separation; understanding this process is a key unsolved problem in polymer science and biophysical chemistry, particularly for nucleic acids, polyanions whose biological functions are intimately related to their high charge density. In the cell, complexation by basic proteins condenses DNA into chromatin, and membraneless organelles formed by liquid-liquid phase separation of RNA and proteins perform vital functions and have been linked to disease...
January 9, 2018: Journal of the American Chemical Society
Aleksandra Ivanova, Kristina Ivanova, Javier Hoyo, Thomas Heinze, Susana Sanchez-Gomez, Tzanko Tzanov
Bacteria-mediated diseases are a global healthcare concern due to the development and spread of antibiotic resistant strains. Cationic compounds are considered membrane active biocidal agents having a great potential to control bacterial infections, while limiting the emergence of drug resistance. Herein, the versatile and simple Layer-by-Layer (LbL) technique was used to coat alternating multilayers of an antibacterial aminocellulose conjugate and the biocompatible hyaluronic acid on biocompatible polymer nanoparticles (NPs), taking advantage of the nano-size of these otherwise biologically inert templates...
January 9, 2018: ACS Applied Materials & Interfaces
Román-Hidalgo Cristina, Martín-Valero María Jesús, Fernández-Torres Rut, Bello-López Miguel Ángel
The use of polymer inclusion membranes (PIMs) as support of 1-octanol liquid membrane in electromembrane extraction (EME) procedure is proposed. Synthesis of PIMs were optimized to a composition of 29% (w/w) of cellulose triacetate as base polymer and 71% (w/w) of Aliquat®336 as cationic carrier. Flat PIMs of 25µm thickness and 6mm diameter were used. EME protocol was implemented for the simultaneous extraction of four non-steroidal anti-inflammatory drugs (NSAIDs) (salicylic acid, ketoprofen, naproxen and ibuprofen) and four highly polar acidic drugs (anthranilic acid, nicotinic acid, amoxicillin and hippuric acid)...
March 1, 2018: Talanta
Markus Hansch, Benjamin Hämisch, Ralf Schweins, Sylvain Prévost, Klaus Huber
The dilute solution behavior of sodium poly(styrene sulfonate) is studied in the presence of trivalent Al3+ and bivalent Ba2+ cations at various levels of excess NaCl. The study evaluates the phase behavior and the morphology of the polyelectrolyte chains with increasing extent of decoration with the Al3+ and Ba2+ cations and analyses the effect of temperature on these decorated chains. The phase behavior is presented in the form of the cation concentration versus the respective poly(styrene sulfonate) concentration, recorded at the onset of precipitation...
January 7, 2018: Journal of Chemical Physics
Rajni Bala, Anuradha Swami, Ilja Tabujew, Kalina Peneva, Nishima Wangoo, Rohit K Sharma
A novel detection platform with high malathion specificity has been developed, which operates based on the signal response in the fluorescence of CdTe@CdS quantum dots (QDs). The designed nanoprobe comprises of QDs, poly(N-(3-guanidinopropyl)methacrylamide) homopolymer (PGPMA) and malathion specific aptamer. The interaction of aptamer with malathion results in switching off of the fluorescence signal of the probe due to the availability of the cationic polymer, which causes quenching of the QDs. However, in the absence of malathion, the polymer interacts with the aptamer, via electrostatic interactions thereby rendering the fluorescence of QDs unaffected...
December 22, 2017: Biosensors & Bioelectronics
Yugyeong Kim, Saji Uthaman, Md Nurunnabi, Sudipta Mallick, Keun Sang Oh, Sun-Woong Kang, Sungpil Cho, Han Chang Kang, Yong-Kyu Lee, Kang Moo Huh
We synthesized a new cationic AB2 miktoarm block copolymer consisting of one poly (ethylene glycol) (PEG) block and two cationic poly (l-lysine) (PLL) blocks, wherein the PLL blocks were conjugated to the PEG blocks with or without a bioreducible linker (disulfide bonds). Bioreducible and non-bioreducible miktoarm block copolymers (mPEG-(ss-PLL)2 and mPEG-PLL2) were prepared for efficient gene delivery as a non-viral gene delivery approach. Both cationic copolymers (bioreducible and nonbioreducible) efficiently formed the nanopolyplexes with plasmid DNA (pDNA) through electrostatic interaction at different weight ratio of polymer and pDNA...
January 2, 2018: International Journal of Biological Macromolecules
Jian Jun Liu, Ying Dong, Li Zhen Chen, Ling Wang, Shu Biao Xia, Chang Cang Huang
Naphthalenediimides, a class of organic dyes with an expanded π-electron-deficient plane, have attracted considerable interest because of their photoinduced electron transfer from neutral organic moieties to stable anionic radicals. This makes them excellent candidates for organic linkers in the construction of photochromic coordination polymers. Such a photochromic two-dimensional coordination polymer has been prepared using N,N'-bis(pyridin-4-ylmethyl)naphthalene-1,8:4,5-bis(dicarboximide) (DPMNI). In crystallization tubes, upon slow diffusion of an MeOH solution of cadmium perchlorate into a CHCl3 solution of DPMNI, the complex poly[[bis[μ2-2,7-bis(pyridin-4-ylmethyl)benzo[imn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetrone-κ2N:N']bis(perchlorato-κO)cadmium(II)] chloroform tetrasolvate], {[Cd(C26H16N4O4)2(ClO4)2]·4CHCl3}n, (I), was obtained...
January 1, 2018: Acta Crystallographica. Section C, Structural Chemistry
Daisuke Koyama, Harvey J A Dale, Andrew J Orr-Ewing
Photoredox catalysis has driven a revolution in the field of organic chemistry, but direct mechanistic insights into reactions of genuine synthetic utility remain relatively scarce. Herein we report ultrafast time-resolved spectroscopic observation of a bimolecular organocatalysed photoredox reaction, from catalyst photoexcitation through to photoinduced electron transfer (PET) and intermediate formation, using transient vibrational and electronic absorption spectroscopy with sub-picosecond time resolution...
January 4, 2018: Journal of the American Chemical Society
Xiu-Tang Zhang, Hong-Tai Chen, Bin Li, Guang-Zeng Liu, Xin-Zheng Liu
Hydrothermal reactions of aromatic terphenyl-4,2'',5'',4'-tetracarboxylic acid (H4tta) and transitional metal cations in the presence of two flexible N-donor ancillary ligands afforded four novel coordination polymers, namely, {[Zn(tta)0.5(m-bimb)]·H2O}n (1), [Ni2(tta)(m-bimb)2(H2O)]n (2), [Ni(H2tta)(o-bimb)·H2O]n (3), and [Cd(tta)0.5(o-bimb)]n (4), from solvothermal reactions in the presence of bis(imidazole) bridging linkers (m-bimb = 1,3-bis(imidazol-1-ylmethyl)benzene, and o-bimb = 1,2-bis(imidazol-1-ylmethyl)benzene)...
January 3, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Jian Xie, Yaxing Wang, Mark A Silver, Wei Liu, Tao Duan, Xuemiao Yin, Lanhua Chen, Juan Diwu, Zhifang Chai, Shuao Wang
There have been numerous studies on emission-color regulation by the adjustment of molar amounts of multiple trivalent lanthanide cations, such as Eu3+, Tb3+, Dy3+, and others, in many types of solid host materials. Although uranyl emission originating from charge-transfer transitions has been well-recognized and investigated for many decades, as of now there is no report on tunable 4f/5f bimodal emission based on heterobimetallic lanthanide(III) and uranyl(VI) compounds. In most cases, complete energy transfer between uranyl(VI) and lanthanide(III) centers was observed...
January 3, 2018: Inorganic Chemistry
Gemma M Adams, Annie Louise Colebatch, Joseph T Skornia, Alasdair I McKay, Heather C Johnson, Guy C Lloyd-Jones, Stuart A Macgregor, Nicholas A Beattie, Andrew S Weller
A systematic study of catalyst structure and charge for the dehydropolymerization of H3B•NMeH2 to form N-methylpolyaminoborane is reported using catalysts based upon neutral and cationic {Rh(Xantphos-R}} fragments, in which PR2 groups are selected from Et, iPr and tBu. The most efficient systems are based upon {Rh(Xantphos-iPr}}, i.e. [Rh(3-P,O,P-Xantphos-iPr)(H)2(2-H3B•NMe3)][BArF4], 6, and Rh(3-P,O,P-Xantphos-iPr)H, 11. While H2 evolution kinetics show both are fast catalysts (ToF ~ 1500 hr-1), and polymer growth kinetics for dehydropolymerization suggest a classical chain growth process for both, neu-tral 11 (Mn = 28,000 g mol-1, Ð = 1...
December 29, 2017: Journal of the American Chemical Society
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