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Journal of Analytical Methods in Chemistry

Yuangui Yang, Ji Zhang, Hang Jin, Jinyu Zhang, Yuanzhong Wang
A fast method was developed by ultra high performance liquid chromatography (UHPLC) for simultaneous determination of polyphyllin I and polyphyllin II. Chemometric analyses including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) based on UHPLC chromatography were used to evaluate 38 batches from six species of Paris. Variable importance of projection was applied to select important peaks. Meanwhile, similarity analysis of UHPLC fingerprint was used to evaluate the sample of Paris polyphylla yunnanensis (PPY) and P...
2016: Journal of Analytical Methods in Chemistry
Giovanni Fusco, Paolo Bollella, Franco Mazzei, Gabriele Favero, Riccarda Antiochia, Cristina Tortolini
A catalase-based (NAF/MWCNTs) nanocomposite film modified glassy carbon electrode for hydrogen peroxide (H2O2) detection was developed. The developed biosensor was characterized in terms of its bioelectrochemical properties. Cyclic voltammetry (CV) technique was employed to study the redox features of the enzyme in the absence and in the presence of nanomaterials dispersed in Nafion® polymeric solution. The electron transfer coefficient, α, and the electron transfer rate constant, ks , were found to be 0...
2016: Journal of Analytical Methods in Chemistry
Felipe Antunes Calil, Juliana Maria Lima, Arthur Henrique Cavalcante de Oliveira, Christiane Mariotini-Moura, Juliana Lopes Rangel Fietto, Carmen Lucia Cardoso
The use of IMERs (Immobilized Enzyme Reactors) as a stationary phase coupled to high performance chromatographic systems is an interesting approach in the screening of new ligands. In addition, IMERs offer many advantages over techniques that employ enzymes in solution. The enzyme nucleoside triphosphate diphosphohydrolase (NTPDase-1) from Trypanosoma cruzi acts as a pathogen infection facilitator, so it is a good target in the search for inhibitors. In this paper, immobilization of NTPDase-1 afforded ICERs (Immobilized Capillary Enzyme Reactors)...
2016: Journal of Analytical Methods in Chemistry
Francisco Anguebes, Lucio Pat, Bassam Ali, Armando Guerrero, Atl V Córdova, Mohamed Abatal, José P Garduza
Attenuated total reflectance-Fourier transform infrared spectrometry and chemometrics model was used for determination of physicochemical properties (pH, redox potential, free acidity, electrical conductivity, moisture, total soluble solids (TSS), ash, and HMF) in honey samples. The reference values of 189 honey samples of different botanical origin were determined using Association Official Analytical Chemists, (AOAC), 1990; Codex Alimentarius, 2001, International Honey Commission, 2002, methods. Multivariate calibration models were built using partial least squares (PLS) for the measurands studied...
2016: Journal of Analytical Methods in Chemistry
Rui-Yun Tian, Chao Lin, Shi-Yu Yu, Sheng Gong, Pan Hu, Yan-Song Li, Zong-Cheng Wu, Yang Gao, Yu Zhou, Zeng-Shan Liu, Hong-Lin Ren, Shi-Ying Lu
The existing assays for detecting brevetoxin (BTX) depend on expensive equipment with a professional operator or on an antibody with limited stability, which requires complex processes, a high cost, and a considerable amount of time. The development of an alternative detection probe is another promising research direction. This paper reports the use of aptamers binding to BTX-2 in an analytical assay using the systematic evolution of ligands by exponential enrichment (SELEX). After 12 rounds of selection, the secondary structures of 25 sequences were predicted...
2016: Journal of Analytical Methods in Chemistry
Deepthika De Silva, Steven Lee, Anna Duke, Siva Angalakurthi, Ching-En Chou, Afshin Ebrahimpour, David E Thompson, Ilona Petrikovics
These studies represent the first report on the intravascular residence time determinations for the cyanide antidote dimethyl trisulfide (DMTS) in a rat model by using high performance liquid chromatography coupled with ultraviolet absorption spectroscopy (HPLC-UV). The newly developed sample preparation included liquid-liquid extraction by cyclohexanone. The calibration curves showed a linear response for DMTS concentrations between 0.010 and 0.30 mg/mL with R(2) = 0.9994. The limit of detection for DMTS via this extraction method was 0...
2016: Journal of Analytical Methods in Chemistry
Alfredo Escudero, Natividad Ramos, M Dolores La Rubia, Rafael Pacheco
This study reflects the effect of extreme storage conditions on several extra virgin olive oil (EVOO) varieties (arbequina, hojiblanca, and picual). The conditions were simulated in the laboratory, by means of heating treatments in stove at different temperatures (40 and 60°C) and times (two and three weeks). The aim is the evaluation of the deterioration of the quality parameters and minority components, which are responsible for the nutritional and therapeutic properties (fatty acids, polyphenols, pigments, and tocopherols), and organoleptic qualities...
2016: Journal of Analytical Methods in Chemistry
Viktor Johánek, Anna Ostroverkh, Roman Fiala, Andrii Rednyk, Vladimír Matolín
The chemical analysis of processes inside fuel cells under operating conditions in either direct or inverted (electrolysis) mode and their correlation with potentiostatic measurements is a crucial part of understanding fuel cell electrochemistry. We present a relatively simple yet powerful experimental setup for online monitoring of the fuel cell exhaust (of either cathode or anode side) downstream by mass spectrometry. The influence of a variety of parameters (composition of the catalyst, fuel type or its concentration, cell temperature, level of humidification, mass flow rate, power load, cell potential, etc...
2016: Journal of Analytical Methods in Chemistry
Patrizia Bocchetta, Carolina Ramírez Sánchez, Antonietta Taurino, Benedetto Bozzini
This paper reports on the quantitative assessment of the oxygen reduction reaction (ORR) electrocatalytic activity of electrodeposited Mn/polypyrrole (PPy) nanocomposites for alkaline aqueous solutions, based on the Rotating Disk Electrode (RDE) method and accompanied by structural characterizations relevant to the establishment of structure-function relationships. The characterization of Mn/PPy films is addressed to the following: (i) morphology, as assessed by Field-Emission Scanning Electron Microscopy (FE-SEM) and Atomic Force Microscope (AFM); (ii) local electrical conductivity, as measured by Scanning Probe Microscopy (SPM); and (iii) molecular structure, accessed by Raman Spectroscopy; these data provide the background against which the electrocatalytic activity can be rationalised...
2016: Journal of Analytical Methods in Chemistry
Rachel Marcella Roland, Showkat Ahmad Bhawani
Molecularly imprinted polymer (MIP) microspheres for Piperine were synthesized by precipitation polymerization with a noncovalent approach. In this research Piperine was used as a template, acrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, and 2,2'-azobisisobutyronitrile (AIBN) as an initiator and acetonitrile as a solvent. The imprinted and nonimprinted polymer particles were characterized by using Fourier transform infrared spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM)...
2016: Journal of Analytical Methods in Chemistry
Gifty E Acquah, Brian K Via, Oladiran O Fasina, Lori G Eckhardt
Fourier transform infrared reflectance (FTIR) spectroscopy has been used to predict properties of forest logging residue, a very heterogeneous feedstock material. Properties studied included the chemical composition, thermal reactivity, and energy content. The ability to rapidly determine these properties is vital in the optimization of conversion technologies for the successful commercialization of biobased products. Partial least squares regression of first derivative treated FTIR spectra had good correlations with the conventionally measured properties...
2016: Journal of Analytical Methods in Chemistry
Jian Huang, Yin'an Ming, Ying Du, Yingru Wang, Ci'en Wang
This study presents the electrochemical degradation of methylene blue (MB) wastewater in a synthetic solution using three-dimensional particle electrodes. The novel particle electrodes were fabricated in this work using the lithium modified rectorite (Li-REC). The adsorption property of the fabricated particle electrodes was studied in a series of experiments. The optimum electrochemical operating conditions of plate distance, cell voltage, and concentration of electrolyte were 2 cm, 9 V, and 0.06 mol L(-1), respectively...
2016: Journal of Analytical Methods in Chemistry
Mary-Luyza Avramescu, Pat E Rasmussen, Marc Chénier
Residual metal impurities in carbon nanotubes (CNTs) provide a means to distinguish CNT from non-CNT sources of elemental carbon in environmental samples. A practical and cost-effective analytical approach is needed to support routine surface monitoring of CNT metal tracers using wipe sampling. Wipe sampling for CNT metal tracers is considered a qualitative indicator of the presence of CNTs, not a quantitative exposure metric. In this study, two digestion approaches (microwave-assisted nitric acid/H2O2 digestion and ultrasonic nitric/HF acid digestion) in conjunction with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) determination were evaluated for their ability to extract metal impurities from CNT particles captured on wipe substrates...
2016: Journal of Analytical Methods in Chemistry
Marcello Manfredi, Elisa Robotti, Greg Bearman, Fenella France, Elettra Barberis, Pnina Shor, Emilio Marengo
Today the long-term conservation of cultural heritage is a big challenge: often the artworks were subjected to unknown interventions, which eventually were found to be harmful. The noninvasive investigation of the conservation treatments to which they were subjected to is a crucial step in order to undertake the best conservation strategies. We describe here the preliminary results on a quick and direct method for the nondestructive identification of the various interventions of parchment by means of direct analysis in real time (DART) ionization and high-resolution time-of-flight mass spectrometry and chemometrics...
2016: Journal of Analytical Methods in Chemistry
Anamaria Hosu, Claudia Cimpoiu, Luminita David, Bianca Moldovan
Cornus species fruits are well known as a rich source of antioxidant compounds responsible for their diverse health benefits. The present study aims to investigate the variation of the total antioxidant capacity of Cornelian cherry (Cornus mas L.) fruits during storage, using high-performance thin-layer chromatography (HPTLC) and two spectrophotometric assays based on different mechanisms: the 2,2-azinobis(3-ethylbenzothiazolyne-6-sulphonic acid) radical cation (ABTS(+∙)) assay and the ferric reducing antioxidant power (FRAP) assay...
2016: Journal of Analytical Methods in Chemistry
Andréa Claudia Oliveira Silva, Luis Carlos Ferreira de Oliveira, Angladis Vieira Delfino, Mario Roberto Meneghetti, Fabiane Caxico de Abreu
The use of nanomaterials, such as nanoparticles and nanotubes, for electrochemical detection of metal species has been investigated as a way of modifying electrodes by electrochemical stripping analysis. The present study develops a new methodology based on a comparative study of nanoparticles and nanotubes with differential pulse anodic stripping voltammetry (DPASV) and examines the simultaneous determination of copper and lead. The glassy carbon electrode modified by gold nanoparticles demonstrated increased sensitivity and decreased detection limits, among other improvements in analytical performance data...
2016: Journal of Analytical Methods in Chemistry
Slavica Filipic, Milica Elek, Marija Popović, Katarina Nikolic, Danica Agbaba
Fast and simple hydrophilic interaction liquid chromatography (HILIC) method was developed and validated for the analysis of moxonidine and its four impurities (A, B, C, and D) in pharmaceutical dosage form. All experiments were performed on the Agilent Technologies 1200 high-performance liquid chromatography (HPLC) system using Zorbax RX-SIL, 250 mm × 4.6 mm, 5 μm column as stationary phase (T = 25°C, F = 1 mL/min, and λ = 255 nm), and mixture of acetonitrile and 40 mM ammonium formate buffer (pH 2...
2016: Journal of Analytical Methods in Chemistry
Giancarlo Biancotto, Roberto Stella, Federica Barrucci, Francesca Lega, Roberto Angeletti
Despite the European ban of using anabolics in food-producing animals, growth promoters might still be illegally used in the European Union. To control the food chain and guarantee consumers' health, there is a need of highly sensitive analytical methods for the identification of marker residues of such treatments. In the present study, a group of bulls (n = 16) received trenbolone acetate (200 mg) and estradiol (40 mg) by a commercial ear implant during a time range of 71 days, and a second group (n = 16) was kept for control...
2016: Journal of Analytical Methods in Chemistry
Gen-Hua Zhao, Cui-Ping Yan, Zi-Sheng Xu, Qian-Qian Gao, Zhi-Peng Chen, Wei-Dong Li
Psoralen and isopsoralen are two isomers and main effective components within Psoralea corylifolia. In order to investigate the salt-processing effect on tissue distribution characters of psoralen and isopsoralen, a sensitive and accurate ultrahigh pressure liquid chromatographic tandem mass spectrometric (UHPLC-MS/MS) method has been developed and validated for simultaneous determination of the 2 components in rats' tissues after administration of the extracts that came from either crude or salt-processed Psoralea corylifolia L...
2016: Journal of Analytical Methods in Chemistry
Anamaria Hosu, Veronica Floare-Avram, Dana Alina Magdas, Ioana Feher, Mihai Inceu, Claudia Cimpoiu
The wine is one of the most consumed drinks over the world, being subjected to falsification or adulteration regarding the variety, vintage, and geographical region. In this study, the influence of different characteristics of wines (type, production year, and origin) on the total phenolic content, total flavonoids content, antioxidant activity, total sugars content, pH, and (18)O/(16)O isotopic ratio was investigated. The differentiation of selected wines on the basis of tested parameters was investigated using chemometric techniques, such as analysis of variance, cluster analysis, and principal component analysis...
2016: Journal of Analytical Methods in Chemistry
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