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https://www.readbyqxmd.com/read/28731685/lipophilic-polycation-vehicles-display-high-plasmid-dna-delivery-to-multiple-cell-types
#1
Yaoying Wu, Adam E Smith, Theresa M Reineke
A class of cationic poly(alkylamidoamine)s (PAAAs) containing lipophilic methylene linkers were designed and examined as in vitro plasmid DNA (pDNA) delivery agents. The PAAAs were synthesized via step-growth polymerization between a diamine monomer and each of four different diacid chloride monomers with varying methylene linker lengths, including glutaryl chloride, adipoyl chloride, pimeloyl chloride, and suberoyl chloride, which served to systematically increase the lipophilicity of the polymers. The synthesized polymers successfully complexed with pDNA in reduced serum medium at N/P ratios of 5 and greater, resulting in polyplexes with hydrodynamic diameters of approximately 1 μm...
July 21, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28730822/distributions-of-polycyclic-aromatic-hydrocarbons-aromatic-ketones-carboxylic-acids-and-trace-metals-in-arctic-aerosols-long-range-atmospheric-transport-and-photochemical-degradation-production-at-polar-sunrise
#2
Dharmendra Kumar Singh, Kimitaka Kawamura, Ayako Yanase, Leonard Barrie
The distributions, correlations and source apportionment of aromatic acids, aromatic ketones, polycyclic aromatic hydrocarbons (PAHs) and trace metals were studied in Canadian high Arctic aerosols. 19 PAHs including minor sulphur-containing heterocyclic PAH (dibenzothiophene) and major 6 carcinogenic PAHs were detected with a high proportion of fluoranthene followed by benzo[k]fluoranthene, pyrene and chrysene. However, in the sunlit period of spring, their concentrations significantly declined likely due to photochemical decomposition...
July 21, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28678292/photocatalytic-decarboxylation-of-diacids-for-the-initiation-of-free-radical-polymerization
#3
Wanfeng Liao, Xiuyuan Ni
Photopolymerization, which is one of the most attractive polymerization methods, has been recently studied for the development of new photoinitiators. Herein, we use a binary mixture of titanium dioxide (TiO2) nanoparticles and carboxylic diacid as a novel photoinitiator to initiate the free radical polymerization of vinyl acetate (VAc). The polymerization of VAc is achieved both in aqueous medium and bulk. The initiation mechanism of TiO2/diacids is studied via nuclear magnetic resonance (NMR) spectroscopy using (13)C labeled diacids as probing molecules...
July 5, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/28671209/new-bio-based-monomers-tuneable-polyester-properties-using-branched-diols-from-biomass
#4
Sacha Pérocheau Arnaud, Linglin Wu, Maria-Angelica Wong Chang, James W Comerford, Thomas J Farmer, Maximilian Schmid, Fei Chang, Zheng Li, Mark Mascal
A family of monomers, including 2,5-hexandiol, 2,7-octandiol, 2,5-furandicarboxylic acid (FDCA), terephthalic acid (TA), and branched-chain adipic and pimelic acid derivatives, all find a common derivation in the biomass-derived platform molecule 5-(chloromethyl)furfural (CMF). The diol monomers, previously little known to polymer chemistry, have been combined with FDCA and TA derivatives to produce a range of novel polyesters. It is shown that the use of secondary diols leads to polymers with higher glass transition temperatures (Tg) than those prepared from their primary diol equivalents...
July 3, 2017: Faraday Discussions
https://www.readbyqxmd.com/read/28657435/enhanced-detection-of-amino-acids-in-hydrophilic-interaction-chromatography-electrospray-tandem-mass-spectrometry-with-carboxylic-acids-as-mobile-phase-additives
#5
Dengyang Yin, Xunxiu Hu, Dantong Liu, Wencheng Du, Haibo Wang, Mengzhe Guo, Daoquan Tang
Liquid chromatography coupled with mass spectrometry technique has been widely used in the analysis of biological targets such as amino acids, peptides, and proteins. In this work, eight common single carboxylic acids or diacids, which contain different pKa have been investigated as the additives to the analysis of amino acids. As the results, carboxylic acid additive can improve the signal intensity of acidity amino acids such as Asp and Glu and the chromatographic separation of basic amino acids such as Arg, His, and Lys...
June 2017: European Journal of Mass Spectrometry
https://www.readbyqxmd.com/read/28652003/comprehensive-two-dimensional-gas-chromatography-mass-spectrometry-of-complex-mixtures-of-anaerobic-bacterial-metabolites-of-petroleum-hydrocarbons
#6
C M Aitken, I M Head, D M Jones, S J Rowland, A G Scarlett, C E West
Anaerobic biotransformation of petroleum hydrocarbons is an important alteration mechanism, both subsurface in geological reservoirs, in aquifers and in anoxic deep sea environments. Here we report the resolution and identification, by comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS), of complex mixtures of aromatic acid and diacid metabolites of the anaerobic biodegradation of many crude oil hydrocarbons. An extended range of metabolites, including alkylbenzyl, alkylindanyl, alkyltetralinyl, alkylnaphthyl succinic acids and alkyltetralin, alkylnaphthoic and phenanthrene carboxylic acids, is reported in samples from experiments conducted under sulfate-reducing conditions in a microcosm over two years...
June 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28636893/controlled-release-from-aspirin-based-linear-biodegradable-poly-anhydride-esters-for-anti-inflammatory-activity
#7
Queeny Dasgupta, Sahitya Movva, Kaushik Chatterjee, Giridhar Madras
This work reports the synthesis of a novel, aspirin-loaded, linear poly (anhydride ester) and provides mechanistic insights into the release of aspirin from this polymer for anti-inflammatory activity. As compared to conventional drug delivery systems that rely on diffusion based release, incorporation of bioactives in the polymer backbone is challenging and high loading is difficult to achieve. In the present study, we exploit the pentafunctional sugar alcohol (xylitol) to provide sites for drug (aspirin) attachment at its non-terminal OH groups...
June 19, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28578576/potential-induced-aggregation-of-anionic-porphyrins-at-liquid-liquid-interfaces
#8
Sho Yamamoto, Hirohisa Nagatani, Hisanori Imura
The adsorption and self-aggregation of anionic porphyrins were studied at the polarized water|1,2-dichloroethane (DCE) interface by polarization-modulation total internal reflection fluorescence (PM-TIRF) spectroscopy. 5,10,15,20-Tetrakis(4-sulfonatophenyl)porphyrin diacid (H4TPPS(2-)) and protoporphyrin IX (H2PP(2-)) exhibited high surface activities at the interface. The selective excitation of interfacial species in PM-TIRF measurements elucidated the potential-induced aggregation mechanism of the porphyrins...
June 13, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28522412/athero-inflammatory-nanotherapeutics-ferulic-acid-based-poly-anhydride-ester-nanoparticles-attenuate-foam-cell-formation-by-regulating-macrophage-lipogenesis-and-reactive-oxygen-species-generation
#9
Rebecca A Chmielowski, Dalia S Abdelhamid, Jonathan J Faig, Latrisha K Petersen, Carol R Gardner, Kathryn E Uhrich, Laurie B Joseph, Prabhas V Moghe
Enhanced bioactive anti-oxidant formulations are critical for treatment of inflammatory diseases, such as atherosclerosis. A hallmark of early atherosclerosis is the uptake of oxidized low density lipoprotein (oxLDL) by macrophages, which results in foam cell and plaque formation in the arterial wall. The hypolipidemic, anti-inflammatory, and antioxidative properties of polyphenol compounds make them attractive targets for treatment of atherosclerosis. However, high concentrations of antioxidants can reverse their anti-atheroprotective properties and cause oxidative stress within the artery...
July 15, 2017: Acta Biomaterialia
https://www.readbyqxmd.com/read/28499946/lipid-drug-conjugate-nanoparticle-as-a-potential-nanocarrier-for-the-oral-delivery-of-pemetrexed-diacid-formulation-design-characterization-ex-vivo-and-in-vivo-assessment
#10
Kriti Soni, Ali Mujtaba, Kanchan Kohli
The present work was to develop lipid drug conjugated (LDC) nanoparticles for the potential oral delivery of pemetrexed diacid (PTX) and evaluation of its in vitro, ex vivo and in vivo potentials. The LDC was prepared by salt formation of PTX with stearic acid and followed by cold homogenization technique to produce the LDC nanoparticles. FTIR analysis of LDC proved the presence of amide bond in LDC powder indicating the conjugation between drug and lipid. LDC nanoparticles was found to have particle size 121...
May 10, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28471081/metal-coordination-assisted-folding-and-guest-binding-in-helical-aromatic-oligoamide-molecular-capsules
#11
Maxime Horeau, Guillaume Lautrette, Barbara Wicher, Virginie Blot, Jacques Lebreton, Muriel Pipelier, Didier Dubreuil, Yann Ferrand, Ivan Huc
The development of foldamer-based receptors is driven by the design of monomers with specific properties. Herein, we introduce a pyridazine-pyridine-pyridazine diacid monomer and its incorporation into helical aromatic oligoamide foldamer containers. This monomer codes for a wide helix diameter and can sequester metal ions on the inner wall of the helix cavity. Crystallographic studies and NMR titrations show that part of the metal coordination sphere remains available and may then promote the binding of a guest within the cavity...
May 4, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28420232/gas-phase-carboxylic-acids-in-a-university-classroom-abundance-variability-and-sources
#12
Shang Liu, Samantha L Thompson, Harald Stark, Paul J Ziemann, Jose L Jimenez
Gas-phase carboxylic acids are ubiquitous in ambient air, yet their indoor occurrence and abundance are poorly characterized. To fill this gap, we measured gas-phase carboxylic acids in real-time inside and outside of a university classroom using a high-resolution time-of-flight chemical ionization mass spectrometer (HRToF-CIMS) equipped with an acetate ion source. A wide variety of carboxylic acids were identified indoors and outdoors, including monoacids, diacids, hydroxy acids, carbonyl acids, and aromatic acids...
May 2, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28353675/nmr-and-ir-investigations-of-strong-intramolecular-hydrogen-bonds
#13
REVIEW
Poul Erik Hansen, Jens Spanget-Larsen
For the purpose of this review, strong hydrogen bonds have been defined on the basis of experimental data, such as OH stretching wavenumbers, νOH, and OH chemical shifts, δOH (in the latter case, after correction for ring current effects). Limits for O-H···Y systems are taken as 2800 > νOH > 1800 cm(-1), and 19 ppm > δOH > 15 ppm. Recent results as well as an account of theoretical advances are presented for a series of important classes of compounds such as β-diketone enols, β-thioxoketone enols, Mannich bases, proton sponges, quinoline N-oxides and diacid anions...
March 29, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28322864/water-soluble-derivatives-of-25-och3-ppd-and-their-anti-proliferative-activities
#14
Wu-Xi Zhou, Yuan-Yuan Sun, Wei-Hui Yuan, Yu-Qing Zhao
(20R)-25-Methoxyl-dammarane-3β,12β,20-triol (25-OCH3-PPD, AD-1) is a dammarane-type sapogenin showing anti-tumor potential. In the search for new anti-tumor agents with higher potency than our previously identified compound 25-OCH3-PPD, 11 novel sulfamic acid and diacid derivatives that could improve water solubility and contribute to good drug potency and pharmacokinetic profiles were designed and synthesized. Their in vitro anti-tumor activities in MCF-7, A-549, HCT-116, and BGC-823 cell lines and one normal cell line were tested by standard MTT assay...
March 18, 2017: Steroids
https://www.readbyqxmd.com/read/28291347/production-of-odd-carbon-dicarboxylic-acids-in-escherichia-coli-using-an-engineered-biotin-fatty-acid-biosynthetic-pathway
#15
Robert W Haushalter, Ryan M Phelan, Kristina M Hoh, Cindy Su, George Wang, Edward E K Baidoo, Jay D Keasling
Dicarboxylic acids are commodity chemicals used in the production of plastics, polyesters, nylons, fragrances, and medications. Bio-based routes to dicarboxylic acids are gaining attention due to environmental concerns about petroleum-based production of these compounds. Some industrial applications require dicarboxylic acids with specific carbon chain lengths, including odd-carbon species. Biosynthetic pathways involving cytochrome P450-catalyzed oxidation of fatty acids in yeast and bacteria have been reported, but these systems produce almost exclusively even-carbon species...
March 21, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28257018/a-13-c-solid-state-nmr-investigation-of-four-cocrystals-of-caffeine-and-theophylline
#16
Nicolas J Vigilante, Manish A Mehta
We report an analysis of the (13)C solid-state NMR chemical shift data in a series of four cocrystals involving two active pharmaceutical ingredient (API) mimics (caffeine and theophylline) and two diacid coformers (malonic acid and glutaric acid). Within this controlled set, we make comparisons of the isotropic chemical shifts and the principal values of the chemical shift tensor. The dispersion at 14.1 T (600 MHz (1)H) shows crystallographic splittings in some of the resonances in the magic angle spinning spectra...
March 1, 2017: Acta Crystallographica. Section C, Structural Chemistry
https://www.readbyqxmd.com/read/28239064/theoretical-aspects-of-triacylglycerin-positional-isomer-separation-on-reverse-phase-high-performance-liquid-chromatography
#17
Tsugihiko Hirano, Keiichi Yokochi, Koretaro Takahashi
The purpose of the present study is to bear our hypothesis and to make a profound discussion on the theoretical aspects of triacylglycerin (TG) positional isomer separation on reverse phase high performance liquid chromatography (HPLC). Authentic triacid TG positional isomers and authentic diacid TG positional isomers were injected to a monomeric and polymeric HPLC. Relationship between TG molecular structure and those elution profiles were carefully analyzed. In polymeric column, thickness of the ODS chain is high compared to monomeric column...
April 3, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28191588/enhancing-fungal-production-of-galactaric-acid
#18
Dorothee Barth, Marilyn G Wiebe
Galactaric (mucic) acid is a symmetrical six carbon diacid which can be produced by oxidation of galactose with nitric acid, electrolytic oxidation of D-galacturonate or microbial conversion of D-galacturonate. Both salts and the free acid of galactarate have relatively low solubility, which may create challenges for a microbial host. Galactaric acid was most soluble at pH values around 4.7 in the presence of ammonium or sodium ions and less soluble in the presence of potassium ions. Solubility increased with increasing temperature...
February 12, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28133655/kinetics-mechanisms-and-ionic-liquids-in-the-uptake-of-n-butylamine-onto-low-molecular-weight-dicarboxylic-acids
#19
Michelle C Fairhurst, Michael J Ezell, Carla Kidd, Pascale S J Lakey, Manabu Shiraiwa, Barbara J Finlayson-Pitts
Atmospheric particles adversely affect visibility, health, and climate, yet the kinetics and mechanisms of particle formation and growth are poorly understood. Multiphase reactions between amines and dicarboxylic acids (diacids) have been suggested to contribute. In this study, the reactions of n-butylamine (BA) with solid C3-C8 diacids were studied at 296 ± 1 K using a Knudsen cell interfaced to a quadrupole mass spectrometer. Uptake coefficients for amines on the diacids with known geometric surface areas were measured at initial amine concentrations from (3-50) × 10(11) cm(-3)...
January 30, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28026947/biodegradable-kojic-acid-based-polymers-controlled-delivery-of-bioactives-for-melanogenesis-inhibition
#20
Jonathan J Faig, Alysha Moretti, Laurie B Joseph, Yingyue Zhang, Mary Joy Nova, Kervin Smith, Kathryn E Uhrich
Kojic acid (KA) is a naturally occurring fungal metabolite that is utilized as a skin-lightener and antibrowning agent owing to its potent tyrosinase inhibition activity. While efficacious, KA's inclination to undergo pH-mediated, thermal-, and photodegradation reduces its efficacy, necessitating stabilizing vehicles. To minimize degradation, poly(carbonate-esters) and polyesters comprised of KA and natural diacids were prepared via solution polymerization methods. In vitro hydrolytic degradation analyses revealed KA release was drastically influenced by polymer backbone composition (e...
January 26, 2017: Biomacromolecules
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