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Tyszczuk-Rotko Katarzyna K Faculty of Chemistry, Department of Analytical Chemistry and Instrumental Analysis, Maria Curie-Skłodowska University, 20-031 Lublin, Poland. Electronic address: - - 2014
The paper describes the fabrication and application of a novel sensor (a boron-doped diamond electrode modified with Nafion and lead films) for the simultaneous determination of paracetamol and ascorbic acid by differential pulse voltammetry. The main advantage of the lead film and polymer covered boron-doped diamond electrode is that the ...
Holland Brendan J BJ Centre for Chemistry and Biotechnology, School of Life and Environmental Sciences, Deakin University, Geelong, Victoria, - - 2014
Sodium polyphosphate is commonly used to enhance chemiluminescence reactions with acidic potassium permanganate through a dual enhancement mechanism, but commercially available polyphosphates vary greatly in composition. We have examined the influence of polyphosphate composition and concentration on both the dual enhancement mechanism of chemiluminescence intensity and the stability of the ...
Kanchana P P Department of Bioelectronics and Biosensors, Alagappa University, 630003 Karaikudi, Tamilnadu, - - 2014
Hydroxyapatite nanoparticles have been synthesized using EDTA as organic modifier by a simple microwave irradiation method and its application for the selective determination of uric acid (UA) has been demonstrated. Electrochemical behavior of uric acid at HA nanoparticle modified glassy carbon electrode (E-HA/GCE) has been investigated by electrochemical impedance spectroscopy ...
Kharrat Nadia - - 2014
Ascorbyl lipophilic derivatives (Asc-C2 to Asc-C18:1), were synthesized in a good yield using lipase from Staphylococcus xylosus produced in our laboratory and immobilized onto silica aerogel. Results showed that esterification had little effect on radical-scavenging capacity of purified ascorbyl esters using DPPH assay in ethanol. However, long chain fatty acids ...
Jiang Jingjing J Key Laboratory of Mesoscopic Chemistry (Ministry of Education), State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China. - - 2014
Sensitive electrochemical sensors were fabricated with reduced graphene oxide-supported Au@Pd (Au@Pd-RGO) nanocomposites by one-step synthesis for individual and simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA) with low detection limits and wide concentration ranges. From the Au@Pd-RGO-modified electrodes, well-separated oxidation peaks and enhanced peak currents of ...
Oestergaard Michael E - - 2014
We compare the duplex stabilizing properties of 2'-fluorinated nucleic acid analogs with furanose and non-furanose ring systems and dissect the relative contributions of hydration, sugar conformation and fluorine configuration towards overall Tm. We find that the stabilization imparted by fluorine substitution is additive over that obtained by restricting the conformation ...
Massin Pascale P Hôpital Lariboisière , Paris , France - - 2014
Abstract Purpose: Fenofibrate reduced progression of diabetic retinopathy in two large randomized studies. The effect of 135 mg fenofibric acid on diabetic macular edema (DME) was evaluated in subjects with existing DME. Methods: In this double-blind, randomized, placebo-controlled study, 110 subjects with DME not requiring immediate photocoagulation or intraocular treatment with ...
Gao Xiaoxin X College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing, 210009, People's Republic of - - 2014
Burkholderia sp. EG13 with high ethylene glycol-oxidizing activity was isolated from soil, which could be used for the synthesis of glycolic acid from the oxidation of ethylene glycol. Using the resting cells of Burkholderia sp. EG13 as biocatalysts, the optimum reaction temperature and pH were 30 °C and 6.0, respectively. After ...
Tai Akihiro A a Faculty of Life and Environmental Sciences , Prefectural University of Hiroshima , Shobara , - - 2014
A single-step synthesis of 3-O-ethyl-l-ascorbic acid was performed without the induction of protecting groups. Sodium l-ascorbate reacted with ethyl bromide in DMSO to give 3-O-Ethylascorbic acid in a yield of 51.0%. 3-O-ethylascorbic acid enhanced dibutyryl cyclic AMP-induced neurite outgrowth in PC12 cells.
Islam Ariful A Department of Organ - - 2014
Low placental fatty acid (FA) transport during the embryonic period has been suggested to result in fetal developmental disorders and various adult metabolic diseases, but the molecular mechanism by which FAs are transported through the placental unit remains largely unknown. The aim of this study was to examine the distribution ...
Ma Ye Y State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China. - - 2014
A three dimensional graphene network (3DGN)@WO3 nanowire (NW) sensor is proposed which can perform colorimetric and electrochemical sensing techniques to detect H2O2, ascorbic acid and dopamine. The 3DGN provides three functions: anchoring, separating, conducting, while the WO3 NWs maximize surface area and catalyse reactions.
Veerakumar Pitchaimani P Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. - - 2014
Carbon porous materials (CPMs) with high surface areas up to 2660 m(2) g(-1), directly fabricated by a facile microwave-assisted route, were applied to the electrochemical detection of dopamine (DA). The CPM-modified electrodes exhibited excellent selectivity, a desirable detection limit (2.9 nM), and extraordinary sensitivity (2.56 mA μM(-1) cm(-2)) for detection ...
Lokman Ibrahim M IM Catalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra - - 2014
In the current research work, effect of microwave irradiation energy on the esterification of palm fatty acid distillate (PFAD) to produce PFAD methyl ester / biodiesel was intensively appraised. The PFAD is a by-product from refinery of crude palm oil consisting >85% of free fatty acid (FFA). The esterification reaction ...
Chen Xi X Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München - - 2014
The kinetics of the reactions of carbocations with carbanions 1 derived from 5-benzyl-substituted Meldrum's acids 1-H (Meldrum's acid=2,2-dimethyl-1,3-dioxane-4,6-dione) were investigated by UV/Vis spectroscopic methods. Benzhydryl cations Ar2 CH(+) added exclusively to C-5 of the Meldrum's acid moiety. As the second-order rate constants (kC ) of these reactions in DMSO followed ...
Kuo Chao-Yin - - 2014
In this study, TiO2/zeolite (TZ)-based composite was utilized to degrade bisphenol A (BPA) under ultraviolet (UV) irradiation. The effects of the TiO2 and Cu2O doses in TZ and Cu2O/TiO2/zeolite (CTZ) on the rate of BPA removal were identified, respectively. The surface area of TZ declined as the TiO2 loading increased. ...
Todoroki Kenichiro K Laboratory of Analytical and Bio-Analytical Chemistry, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, - - 2014
A sensitive, versatile, and reproducible automatic analyzer for highly polar carboxylic acids based on a fluorescence derivatization-liquid chromatography (LC) method was developed. In this method, carboxylic acids were automatically and fluorescently derivatized with 4-(N,N-dimethylaminosulfonyl)-7-piperazino-2,1,3-benzoxadiazole (DBD-PZ) in the presence of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride by adopting a pretreatment program installed in an LC ...
Derrar S N SN Laboratoire de Microscopie, Microanalyse de la matière et Spectroscopie Moléculaire, Université Djilali Liabès, B.P 89, Sidi Bel Abbès, 22000, - - 2014
The first hyperpolarizabilities β of the natural aromatic amino acids tryptophan and tyrosine have been investigated using several methods and basis sets. Some of the theoretical results obtained were compared to the only experimental hyper-Rayleigh scattering data available. The sensitivity of tryptophan to its local environment was analyzed by constructing ...
Wang Shaohua - - 2014
AbnZ1, with optimal pH of 6.0 and optimal temperature of 40 C, was a cold-adapted endo-1,5-α-l-arabinanase encoded by the gene abnZ1 from Paenibacillus polymyxa Z6. The specific activity of AbnZ1 remained 54.1% of maximum at 5 C. For the desire of AbnZ1 application in acidic condition, three basic hsitidine (His) ...
McCarthy Brian D BD Department of Chemistry, University of North Carolina , Chapel Hill, North Carolina 27599-3290, United - - 2014
Molecular catalysts for electrochemically driven hydrogen evolution are often studied in acetonitrile with glassy carbon working electrodes and Brønsted acids. Surprisingly, little information is available regarding the potentials at which acids are directly reduced on glassy carbon. This work examines acid electroreduction in acetonitrile on glassy carbon electrodes by cyclic ...
Gayathri T T Department of Civil Engineering, Regional Centre of Anna University, Tirunelveli, - - 2014
In this investigation, the application of citric acid was explored for the removal of extracellular polymeric substance (EPS) from waste activated sludge (WAS), followed by ultrasonic pretreatment, which enhanced the subsequent anaerobic biodegradability. EPS was removed with 0.05g/g SS of citric acid. The chemical oxygen demand (COD) solubilization and suspended ...
Anaya Susana - - 2014
High performance polysulfone/γ-alumina biocompatible nanocomposites are reported for the first time and the effects of γ-alumina surface modification are explored. We show that some fatty acids chemisorb over the surface of γ-alumina forming nano-sized self-assembled structures. These structures present thermal transitions at high temperatures, 100 ºC higher than the melting ...
Arora Kashima K Department of Physics and Astrophysics, University of Delhi, Delhi 110007, India. - - 2014
The development of a noninvasive test for uric acid has been the holy grail of uric acid detection research over the last decade. In the present work, a novel matrix comprising of a NiO thin film (a biocompatible material) loaded with Ni microdiscs was prepared on an ITO-coated glass substrate ...
Yu Xiaowen X Department of Chemistry, Tsinghua University, Beijing 100084, People's Republic of China. - - 2014
Electrochemical detection of dopamine plays an important role in medical diagnosis. In this paper, we report a three-dimensional (3D) interpenetrating graphene electrode fabricated by electrochemical reduction of graphene oxide for selective detection of dopamine. This electrochemically reduced graphene oxide (ErGO) electrode was used directly without further functionalization or blending with ...
Yoshiyama Yoko Y Research Division of Microbial Sciences, Kyoto University, Kitashirakawa Oiwake-Cho, Sakyo-ku, Kyoto 606-8502, - - 2014
Trehalose confers protection against various environmental stresses on yeast cells. In this study, trehalase gene deletion mutants that accumulate trehalose at high levels showed significant stress tolerance to acetic acid. The enhancement of trehalose accumulation can thus be considered a target in the breeding of acetic acid-tolerant yeast strains.
Yang Xiuli X Jiangxi Key Laboratory of Mining Engineering, Jiangxi University of Science and Technology, Jiangxi 341000, China; Faculty of Resource and Environmental Engineering, Jiangxi University of Science and Technology, Jiangxi 341000, China. Electronic address: - - 2014
With an increase in number of waste nickel-metal hydride batteries, and because of the importance of rare earth elements, the recycling of rare earth elements is becoming increasingly important. In this paper, we investigate the effects of temperature, hydrochloric acid concentration, and leaching time to optimize leaching conditions and determine ...
Taylor Jonathan C JC Nuclear Medicine Department, Sheffield Teaching Hospital NHS Foundation Trust, Sheffield, - - 2014
Measurements of SeHCAT (tauroselcholic [75selenium] acid) retention have been used to diagnose bile acid malabsorption for a number of years. In current UK practice the vast majority of centres calculate uptake using an uncollimated gamma camera. Because of ever-increasing demands on gamma camera time, a new 'probe' detector was designed, ...
Zhang Qing Q School of Chemistry and Chemical Engineering & Anhui Province Key Laboratory of Environment-friendly Polymer Materials, Anhui University, Hefei 230601, - - 2014
Two carbazole-based dye molecules: 3-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-2-cyano-acylic acid (D3) and 3-[5-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-thiophen-2-yl]-2-cyan-acylic acid (D4) were synthesized by an approach from carbazole derivate using Vilsmeier-Haack, Suzuki cross-coupling and Knoevenagel reactions. Their physical and electrochemical properties were investigated. D3 and D4 exhibit different optical properties, such as UV absorption, photoluminescence, fluorescence quantum yield and fluorescence ...
Maiyalagan Thandavarayan - - 2014
Supported tungsten carbide is an efficient and vital nanomaterial for the development of high performance, sensitive and selective electrochemical sensors. In this work, tungsten carbide with tube-like nanostructures (WC NTs) supported platinum nanoparticles (PtNPs) are synthesized and explored as an efficient catalyst towards electrochemical oxidation of oxalic acid for the ...
Subramanian Palaniappan P Institut de Recherche Interdisciplinaire (IRI), CNRS USR 3078, Université Lille1, Parc de la Haute Borne, 50 avenue de Halley, BP 70478, 59658 Villeneuve d'Ascq, France. - - 2014
Coating boron-doped diamond nanowires (BDD NWs) with a conducting polymer, poly[3-(pyrrolyl)carboxylic acid], has been reported. Polymer coating was achieved through electropolymerization of 3-(pyrrolyl)carboxylic acid at the electrode interface by amperometrically biasing the BDD NWs interface until a predefined charge has passed. The poly[3-(pyrrolyl)carboxylic acid] modified BDD NWs (PPA-BDD NWs) were ...
Biswas Mrinmoy M Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India. - - 2014
The thermal phase behaviors of a series of newly designed 1-alkyl-3-methylimidazolium ionic liquids (ILs) of different chain length fatty acid carboxylate anions are investigated. The length of the alkyl chain of the carboxylate anion in IL influences the phase transition temperature of their crystalline solid phase and the mesophase stability. ...
Ye Sujuan S College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Normal University, Jinan 250014, P. R. China. - - 2014
A novel surface-enhanced Raman scattering (SERS) detection system is developed for proteins and nucleic acids based on a triple-helix molecular switch for multiple cycle signal amplification, achieving high sensitivity, universality, rapid analysis, and high selectivity.
Kamimura Akio A Department Applied Molecular Bioscience, Graduate School of Medicine, Yamaguchi University, Ube 755-8611 (Japan), Fax: (+81) 836-85-9231. - - 2014
An efficient transformation of polyamides to ω-hydroxy alkanoic acids was achieved. Treatment of nylon-12 with supercritical MeOH in the presence of glycolic acid gave methyl ω-hydroxydodecanoate in 85 % yield and the alcohol/alkene selectivity in the product was enhanced to up to 9.5:1. The use of (18) O-enriched acetic acid for ...
Bielinski Elizabeth A - - 2014
Formic acid (FA) is an attractive compound for H2 storage. Currently, the most active catalysts for FA dehydrogenation use precious metals. Here, we report a homogeneous Fe catalyst that when used with a Lewis acid (LA) co-catalyst, gives approximately 1,000,000 turnovers for FA dehydrogenation. To date, this is the highest ...
Krol Elizaveta E LOEWE Center for Synthetic Microbiology, Department of Biology, Philipps-University Marburg, 35032 Marburg, - - 2014
Quorum sensing (QS) using N-acyl homoserine lactones (AHLs) as signal molecules is a common strategy used by diverse Gram-negative bacteria. A widespread mechanism of AHL sensing involves binding of these molecules by cytosolic LuxR-type transcriptional regulators, which requires uptake of external AHLs. The outer membrane is supposed to be an ...
Bayer Anton A Institut für Organische Chemie, Universität des Saarlandes, Im Stadtwald, Geb. C4.2, 66041 Saarbrücken (Germany), Fax: - - 2014
Chelated amino acid ester enolates are excellent nucleophiles for ruthenium-catalyzed allylic alkylations. Although [Cp*Ru(MeCN)3 ]PF6 was found to be the most reactive catalyst investigated, with the resulting allyl complexes reacting at temperatures as low as -78 °C, unfortunately the process took place with only moderate regio- and diastereoselectivity. In contrast, [(p-cymene)RuCl2 ...
Katayev Dmitry D FB Chemie-Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. Geb. 54, 67663 Kaiserslautern (Germany), Fax: - - 2014
Various (hetero)arenecarboxylic acids were converted to the corresponding Daugulis amides and nitrated selectively in the ortho-position in the presence of [CuNO3 (PPh3 )2 ] and AgNO2 at 50 °C. A microwave-assisted saponification allows regenerating the carboxylate group within minutes, which may then be removed tracelessly by protodecarboxylation, or substituted by aryl- ...
Wang Jin J School of Pharmaceutical Sciences, Hebei Medical University, Shijiazhuang 050017, P.R. - - 2014
A rapid and sensitive high-performance liquid chromatographic (HPLC) method was developed for the simultaneous separation and determination of chlorogenic acid, caffeic acid, alantolactone and isoalantolactone in Inula helenium. The HPLC separation was performed on an Elite Hypersil C18 column (200 × 4.6 mm i.d., 5 µm particle size) with a ...
Soriano-Maldonado Pablo P Departamento de Química y Física, Universidad de Almería, Campus de Excelencia Internacional Agroalimentario, CEIA3, Edificio CITE I, Carretera de Sacramento s/n., 04120 La Cañada de San Urbano, Almería, - - 2014
Taking advantage of the catalytic promiscuity of L-carbamoylase from Geobacillus stearothermophilus CECT43 (BsLcar) and N-succinyl-amino acid racemase from Geobacillus kaustophilus CECT4264 (GkNSAAR), we have evaluated the production of different optically pure L-α-amino acids starting from different racemic N-formyl- and N-carbamoyl-amino acids using a dynamic kinetic resolution approach. The enzymes were ...
Fernandes Diana M DM REQUIMTE/Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal. Electronic address: - - 2014
A new modified electrode based on N-doped carbon nanotubes functionalized with Fe3O4 nanoparticles (Fe3O4@CNT-N) has been prepared and applied on the simultaneous electrochemical determination of small biomolecules such as dopamine (DA), uric acid (UA) and ascorbic acid (AA) using voltammetric methods. The unique properties of CNT-N and Fe3O4 nanoparticles individually ...
Lin Yu Hong YH Laboratory of Membrane Biochemistry and Biophysics, NIAAA, NIH, Bethesda, MD, USA, - - 2014
A methodology combining finger-pricked blood sampling, microwave accelerated fatty acid assay, fast gas chromatography data acquisition, and automated data processing was developed, evaluated and applied to a population study. Finger-pricked blood was collected on filter paper previously impregnated with 0.05 mg of the antioxidant butylated hydroxytoluene and air-dried at room temperature. ...
Colon Marta - - 2014
Migration of green tea components from an active packaging material containing green tea extract was performed in water and 3% acetic acid in water. The migration values for acid simulant were much higher than the values obtained in water. The influence of the acidic media in solutions of catechins standards ...
Lavanya N N Department of Bioelectronics and Biosensors, Alagappa University, Karaikudi-630 003, Tamilnadu, - - 2014
A novel folic acid biosensor has been fabricated using Cu doped SnO2 nanoparticles (NPs) synthesized by a simple microwave irradiation method. Powder XRD and TEM studies confirmed that both the pure and Cu doped SnO2 (Cu: 0, 10, 20wt%) crystallized in tetragonal rutile-type structure with spherical morphology. The average crystallite ...
Rasouli M M Department of Clinical Biochemistry, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Mazandaran, Iran. - - 2014
Phenol-sulfuric acid reagent is used to measure the concentration of glyco-polymers and -conjugates. There are several uncertainties on glycogen measurement in the tissues. We aimed to improve phenol-sulfuric reagent for microassay of glucose based-glycogen in small tube or microplate. The condition of the reaction was optimized and scaled down for ...
Sun Jiaduo J College of Biotechnology and Pharmaceutical Engineering, Nanjing Technology University, 30 Puzhu South Road, Nanjing, Jiangsu, 211816, - - 2014
To improve the production of D-lactic acid, atmospheric and room temperature plasma (ARTP) was used to generate mutations in Sporolactobacillus sp. Y2-8. An efficient mutant YBS1-5 was rapidly isolated by implanting ARTP twice with a 100 W radio-frequency power input, 10 standard liters per minute of the helium flow, and ...
Ma Lichao L State Key Laboratory of Grassland Agro-ecosystems, School of Pastoral Agricultural Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China, - - 2014
GDP-mannose 3', 5'-epimerase (GME) catalyses the conversion of GDP-D-mannose to GDP-L-galactose, an important step in the ascorbic acid (ascorbic acid) biosynthetic pathway in higher plants. In this study, a novel cDNA fragment (MsGME) encoding a GME protein was isolated and characterised from alfalfa (Medicago sativa). An expression analysis confirmed that ...
Tian Zhenlin Z State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, PR China. wpzhu@ecust.edu.cn - - 2014
A fluorescent probe () based on an unnatural amino acid (UAA) is developed for the detection of phenylalanine ammonia lyase (PAL). In the presence of PAL, is catalytically deaminated to ortho-amino-transcinnamic acid (o-a-CA), which shows a remarkable "off-on" fluorescence signal. Thus, the probe enables direct visualization of the PAL activity ...
Song Ye Y Key Laboratory of Soft Chemistry and Functional Materials of Education Ministry, Nanjing University of Science and Technology, Nanjing 210094, - - 2014
The electroactivity of polyaniline (PANI) can be solely retained in acidic media. However, the acidity requirement greatly limits its potential applications such as biosensors and anticorrosion, where neutral circumstances have to be faced. Herein, PANI is conformally loaded into anodic titanium oxide (ATO) nanotubes by electrodeposition. The prepared PANI-ATO hybrid ...
Akasaka Naoki N Institute of Applied Microbiology, Marukan Vinegar Co. Ltd., 5-6 Koyo-cho West, Higashinada-ku, Kobe, Hyogo 658-0033, - - 2014
Vinegar with increased amounts of branched-chain amino acids (BCAAs; valine, leucine and isoleucine) is favorable for human health as BCAAs decrease diet-induced obesity and hyperglycemia. To construct Gluconacetobacter europaeus which produces BCAAs, leucine responsive regulator (GeLrp) is focused and two Gelrp mutants were constructed. Wild-type KGMA0119 didn't produce significant amount ...
Dey Tapati Bhanja TB Lignocellulose Biotechnology Laboratory, Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, - - 2014
Solid-state fermentation (SSF) at 30°C for 72 h with four Generally Recognized as Safe (GRAS) filamentous fungi (Aspergillus oryzae NCIM 1212, Aspergillus awamori MTCC No. 548, Rhizopus oligosporous NCIM 1215 and Rhizopus oryzae RCK2012) showed high efficiency for the improvement of water soluble total phenolic content (TPC) and antioxidant properties ...
Brayden David J DJ School of Veterinary Medicine, Veterinary Sciences Centre and Conway Institute, University College Dublin, Room 214 Belfield, Dublin 4, Ireland, - - 2014
10-undecylenic acid (UA) is an OTC antifungal therapy and a nutritional supplement. It is an unsaturated medium chain fatty acid (MCFA) derivative, so our hypothesis was that its 11-mer sodium salt, uC11, would improve intestinal permeation similar to the established enhancer, sodium caprate (C10), but without the toxicity of the ...
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