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International Journal of Analytical Chemistry

Bomi Nam, Sunil Babu Paudel, Jin-Baek Kim, Chang Hyun Jin, Dongho Lee, Joo-Won Nam, Ah-Reum Han
Three monoterpenes, namely, 9-hydroxy isoegomaketone ( 1 ), isoegomaketone ( 2 ), and perilla ketone ( 3 ), were successfully separated from the supercritical carbon dioxide (SC-CO2 ) extract of the leaves of Perilla frutescens var. crispa (cv. Antisperill; Lamiaceae) by centrifugal partition chromatography (CPC). To obtain large quantities of these materials required for studies on their mechanism of action and in vivo effectiveness in inflammation, we used CPC because of its high loading capacity and reproducibility to purify the three compounds...
2019: International Journal of Analytical Chemistry
Jie Sun, Fang Tian, Ying Zhang, Menghua Wu, Runqian Mao, Zhiyong Le, Dongjin Xu, Hui Cao, Zhiguo Ma
Guang Dilong is a Traditional Chinese Medicine prepared from the dried body of Pheretima aspergillum (E. Perrier), a species of earthworm. However, preparations of Guang Dilong may be adulterated by other species and a method of quality control is needed. A method was developed to analyze and authenticate commercial Guang Dilong, utilizing ultra-high performance liquid chromatography (UHPLC) coupled with diode array detection (DAD). Equipment included an Acquity UPLC HSS T3 column (100 mm × 2.1 mm, 1.8  μ m)...
2019: International Journal of Analytical Chemistry
Mehwish Sharif, Madeeha Batool, Sohail Chand, Zahoor Hussain Farooqi, Syed Azhar Ali Shah Tirmazi, Makshoof Athar
Examination and comparison of fountain pen inks are very important in forensic questioned documents examination in developing countries where the chances of fraud are greater in cases of cheques, marriage papers, entry of birth and death, etc. In this study, fountain pen inks of blue, black, green, and red colours that are commercially used in Pakistan have been discriminated by UV-Vis spectroscopy, TLC, and FTIR spectroscopy. We have calculated and compared the results in terms of discriminating power. UV/Visible Spectroscopy of fountain pen inks of different brands showed different composition despite their similar colours...
2019: International Journal of Analytical Chemistry
Walaa El-Alfy, Omnia A Ismaiel, Magda Y El-Mammli, Abdalla Shalaby
A simple RP-HPLC-PDA method for determination of atenolol (ATN) and trimetazidine (TMZ) in human urine and tablets has been developed. Analytes were separated on a Caltrex BI column (125× 4.0 mm, 5 μ m) with 25mM potassium dihydrogen phosphate pH 3.3, methanol, and acetonitrile mobile phases. The PDA detector was operated at 210 nm for TMZ and 225 nm for ATN and the flow rate was 1.0 mL/ min. Linearity was obtained over a concentration range of (1.0-100 μ g/mL) for both analytes in standard solutions and the method was successfully applied for determination of target analytes in their pharmaceutical tablets...
2019: International Journal of Analytical Chemistry
Nicola Marchetti, Pier Paolo Giovannini, Martina Catani, Luisa Pasti, Alberto Cavazzini
The retention mechanism of four major carotenoids, two xanthophylls (i.e., lutein and zeaxanthin) and two carotenes (i.e., lycopene and β -carotene), was investigated in reversed-phase liquid chromatography with the aim of thermodynamic analysis. The experimental variables considered in this study were the composition of mobile phase (MP) and the temperature. Chromatographic elutions were undertaken under linear, isocratic conditions by using a C18 stationary phase, four different MP compositions (by varying the ratio methanol/acetonitrile from 66...
2019: International Journal of Analytical Chemistry
Jessica Torres-Gamez, Jose A Rodriguez, M Elena Paez-Hernandez, Carlos A Galan-Vidal
A method using UV-Vis spectroscopy and multivariate tools for simultaneous determination of glucose and cholesterol was developed in this paper. The method is based on the development of the reaction between the analytes (cholesterol and glucose) and enzymatic reagents. The spectra were analyzed by partial least squares regression and artificial neural networks. The precision estimated between nominal and calculate concentration demonstrate that artificial neural network model was adequate to quantify both analytes in serum samples, since the % relative error obtained was in the interval from 5...
2019: International Journal of Analytical Chemistry
Tahisa Marcela Pedroso, Ann Van Schepdael, Hérida Regina Nunes Salgado
An innovative method is validated for the analysis of ertapenem sodium by capillary electrophoresis using potassium phosphate buffer 10 mM pH 7 and 15 kV voltage, in the concentration range of 70 to 120  μ g mL-1 . Ertapenem had a migration time of 3.15 minutes and the linearity curve was y = 2281.7 x - 24495 with a R2 = 0.9994. Thus, we propose a routine analysis method that meets the principles of green analytical chemistry for the routine analysis of ertapenem sodium by capillary electrophoresis...
2019: International Journal of Analytical Chemistry
Marcela Zanetti Corazza, Vanessa Egea Dos Anjos, Seyyed E Moradi
No abstract text is available yet for this article.
2019: International Journal of Analytical Chemistry
Silvia S Yahagi, Ana C Roveda, Adrielli T Sobral, Ivan P Oliveira, Anderson R L Caires, Roberto S Gomes, Magno A G Trindade
The antioxidant potential of a novel additive, named maleimide p -CH3 , and the synergistic effect on biodiesel stabilization when combined with a traditional synthetic antioxidant (e.g., propyl gallate (PG)) as well as alternative additives (e.g., alizarin (ALZ) and citric acid (CA)) were investigated. The additives were combined in binary and/or ternary blends at low concentrations and their effectiveness against soybean biodiesel oxidation in the absence and presence of metal was tested. The effectiveness of binary and ternary blends was also evaluated by the Rancimat® method and compared with total acid number (TAN)...
2019: International Journal of Analytical Chemistry
Damiano Monticelli, Alessio Castelletti, Davide Civati, Sandro Recchia, Carlo Dossi
Subboiling distillation has been used since two decades for the purification of analytical grade acids from inorganic contaminants and demonstrated an efficient method to obtain pure acids starting from reagent grade chemicals. Nevertheless, the effect of the subboiling parameters on the purity of the distilled acids has never been methodically investigated. Aim of the present research is a systematic evaluation of the subboiling distillation protocol for the production of pure hydrochloric and nitric acid...
2019: International Journal of Analytical Chemistry
Andreas Kiontke, Susan Billig, Claudia Birkemeyer
Modern technical evolution made mass spectrometry (MS) an absolute must for analytical chemistry in terms of application range, detection limits and speed. When it comes to mass spectrometric detection, one of the critical steps is to ionize the analyte and bring it into the gas phase. Several ionization techniques were developed for this purpose among which electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) are two of the most frequently applied atmospheric pressure methods to ionize target compounds from liquid matrices or solutions...
2018: International Journal of Analytical Chemistry
Chengli Zhang, Peng Wang, Guoliang Song
Based on the properties of high temperature and salinity reservoir, the water-soluble polymer with good heat resistance and salt tolerance can be obtained through copolymerization between 2-acrylamide-2-methyl sulfonate monomer (AMPSN) and acrylamide monomer (AM) in water. The star shaped stable complexes (STARPAM) with the star nucleus of β -CD are prepared by living radical polymerization, which can improve the viscosity and change the percolation characteristics of the polymer in porous media. In the article, the performance of the STARPAM (star-shaped polymer) with heat resistance and salt tolerance was evaluated by comparing the viscosification property, heat and salt resistance, calcium and magnesium tolerance, and long-term thermal stability of STARPAM (star-shaped polymer) with those of HPAM (partially hydrolyzed polyacrylamide) and MO-4000 (linear polymer)...
2018: International Journal of Analytical Chemistry
Haidong Wang, Chongning Li, Yanghe Luo, Zhiliang Jiang
The gold nanoparticle reaction of HAuCl4 -H2 O2 was very slow under 60°C, and the as-prepared graphene oxide nanoribbons (GONRs) exhibited strong catalysis of the reaction to form gold nanoparticles (AuNP) that appeared a resonance Rayleigh scattering (RRS) peak at 550 nm. Upon addition of potassium pyroantimonate (PA) ligand, it was adsorbed on the GONRs surface to inhibit the catalysis to cause the RRS peak decreasing. When the analyte of Na+ was added, the coordination reaction between PA and Na+ took place to form the stable complexes of [Na2 (PA)] to release free GONRs catalyst that resulted in the RRS peak increasing linearly...
2018: International Journal of Analytical Chemistry
Catalani Simona, Fostinelli Jacopo, Gilberti Maria Enrica, Orlandi Francesca, Magarini Riccardo, Paganelli Matteo, Madeo Egidio, De Palma Giuseppe
Nickel (Ni) compounds and metallic Ni have many industrial and commercial applications, including their use in the manufacturing of stainless steel. Due to the specific toxicological properties of the different Ni species, there is a growing interest about the availability of analytical methods that allow specific risk assessment, particularly related to exposure to the Ni species classified as carcinogenic. In this paper, we described a speciation method of inorganic Ni compounds in airborne particulate matter, based on selective sequential extractions...
2018: International Journal of Analytical Chemistry
Keishi Suga, Ying-Chen Lai, Miftah Faried, Hiroshi Umakoshi
Amyloid β (A β ) is a potential biomarker of Alzheimer's disease (AD), and its fibrillation behavior is of interest and value. In this study, the A β behaviors on phospholipid membranes were observed by Membrane Surface-Enhanced Raman Spectroscopy (MSERS) method. Phospholipid (PL) membranes, consisting of DMPC and DMPS with a molar ratio of 9:1, were fabricated on gold nanoparticles with diameter of 100 nm (Au@PL). Enhancement of the Raman intensity of Au@PL was increased by A β , with enhancement factor about 40...
2018: International Journal of Analytical Chemistry
Hector Henrique Ferreira Koolen, Clécio Fernando Klitzke, Joe Binkley, Jeffrey Patrick, Ana Cecília Rizatti de Albergaria-Barbosa, Rolf Roland Weber, Márcia Caruso Bícego, Marcos Nogueira Eberlin, Giovana Anceski Bataglion
The performance of gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC-HRTofMS) for characterizing geochemical biomarkers from sediment samples was evaluated. Two approaches to obtain the geochemical biomarkers were tested: (1) extraction with organic solvent and subsequent derivatization and (2) in-situ derivatization thermal desorption. Results demonstrated that both approaches can be conveniently applied for simultaneous characterization of many geochemical biomarkers (alkanes, alkanols, sterols, and fatty acids), avoiding conventional time-consuming purification procedures...
2018: International Journal of Analytical Chemistry
Yan Qiu, Jianlin Huang, Li Jia
A fluorescence sensor for the detection of glutathione based on the fluorescence recovering of the bovine serum albumin-stabilized gold nanoclusters is reported. This study indicates that glutathione restores the copper-ion-quenched fluorescence by coordinating the bound copper ion in the bovine serum albumin molecule used for stabilizing the gold nanocluster through its sulfydryl. Under the experimental conditions, the fluorescence response showed a linear relationship with the concentration of glutathione over the range from 10  µ M to 400  µ M...
2018: International Journal of Analytical Chemistry
Yang Tian, Yue Wang, Shanshan Wu, Zhian Sun, Bolin Gong
Surface-imprinted polymers (MIPs) microspheres with the ability to specifically recognize water-soluble molecules were prepared using self-made monodisperse porous poly(chloromethylstyrene-co-divinylbenzene) beads as the solid-phase matrix and ampicillin (AMP) as the template molecule. MIPs were synthesized using different template molecule: monomer: crosslinker ratios and the optimum preparation ratio were obtained by measuring adsorption. The maximum equilibrium amount of adsorption by the MIPs reached 115...
2018: International Journal of Analytical Chemistry
Akihide Itoh, Masato Ono, Kota Suzuki, Takumi Yasuda, Kazuhiko Nakano, Kimika Kaneshima, Kazuho Inaba
In the present study, ICP-MS with a new hybrid simultaneous preconcentration combining solid phase extraction using chelating resin and iron hydroxide coprecipitation in one batch at a single pH adjustment (pH 6.0) were developed for multielement determination of trace metal ions in seawater. In multielement determination, the present method makes it possible to determine Cr(III), As(V), Se (IV), and other 14 trace metal elements (Ti, V, Co, Ni, Cu, Zn, Zr, Ge, Cd, Sb, Sn, W, Pb, and U) in seawater. Moreover, for speciation analyses of Cr, As, and Se, the pH dependence on recovery for the different chemical forms of Cr, As, and Se was investigated...
2018: International Journal of Analytical Chemistry
Giuseppina Nocca, Cinzia Callà, Stefano Angelo Santini, Adriana Amalfitano, Luca Marigo, Diana Valeria Rossetti, Gianrico Spagnuolo, Massimo Cordaro
A reverse phase high performance liquid chromatographic (RP-HPLC) method was developed for identification and estimation of 18- β -glycyrrhetinic acid (GA) in HepG2 cell line. The analysis was carried out using a JASCO HPLC system with a C-18 (3  μ m) Supelco reversed phase column (150 x 4.7 mm) using a mobile phase of 80% CH3 OH and 20% of CH3 CN: tetrahydrofuran: water (10:80:10, v/v/v). The method was linear in the concentration range of 1.5-120  μ g /mL (n = 5). The LOD and LOQ were determined based on standard deviation of the y-intercept and the slope of the calibration curve...
2018: International Journal of Analytical Chemistry
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