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Journal of Chromatographic Science

Shilpi Chopra, Lauren Ridley, Wyatt R Murphy, John R Sowa, Carolyn S Bentivegna, Nicholas H Snow
Headspace solid-phase microextraction (HS-SPME) was used in combination with gas chromatography-mass spectrometry (GC-MS) for the analysis of polycyclic aromatic hydrocarbons (PAH) at part per billion levels in fish oil samples collected from menhaden fish. The method was initially developed using fish oil from capsules spiked with a standard PAH mixture. The final HS-SPME-GC-MS method presented a linear range from 3 to 1,500 ng/g, with precision for most analytes <10% relative standard deviation. The limits of detection varied from 1 to 7 ng/g depending on the analyte...
September 12, 2018: Journal of Chromatographic Science
Ilona Kiszkiel-Taudul, Barbara Starczewska
A new extraction method was developed for isolation of the antihistaminic drugs (histamine H2 receptor antagonists) famotidine (FMT) and nizatidine (NZT) from aqueous samples. A low solvent consumption method using dispersive liquid-liquid microextraction (DLLME) was applied for this purpose. The parameters of the isolation, namely, volume of extraction and disperser solvents, pH of sample and shaking time were optimized. The influence of foreign substances on the extraction process was also studied. After separation of FMT and NZT using DLLME, the analytes in organic extracts were determinated by high-performance liquid chromatography combined with UV spectrophotometry and liquid chromatography connected with tandem mass spectrometry (LC-MS-MS)...
August 31, 2018: Journal of Chromatographic Science
Anurak Choemang, Kesara Na-Bangchang
A simple, sensitive, selective and reproducible method based on liquid chromatography was developed for the determination of piperaquine in human plasma samples. Sample preparation involved a single step liquid-liquid extraction by organic solvents (hexane: tert-butyl methylether at the ratio of 1:1, v:v). Piperaquine was separated from the internal standard mefloquine on a reversed-phase C18 column, with the mobile phase consisting of a mixture of acetonitrile and 0.1% trichloroacetic acid (in water) (15:85, v:v) running at a flow rate of 1...
August 31, 2018: Journal of Chromatographic Science
Farah Safdel, Fariba Safa
In this work, a combination of Xu and atom-type-based AI topological indices (TIs) were employed for quantitative structure-retention relationship (QSRR) study of monomethylalkanes (MMAs). A total of 196 temperature-programmed gas chromatographic retention indices corresponding to all C4-C30 MMAs on OV-1 stationary phase have been used in QSRR modeling. Results of the study showed that an artificial neural network (ANN) with 4-9-1 topology and Levenberg-Marquardt training algorithm can predict the retention indices with high degree of accuracy...
August 28, 2018: Journal of Chromatographic Science
Varaprasad Jagadabi, P V Nagendra Kumar, Kasthuri Mahesh, Srinivasu Pamidi, L A Ramaprasad, D Nagaraju
A stability-indicating ultraperformance liquid chromatographic method has been developed for the quantitative determination of degradation products and process-related impurities of daclatasvir in a pharmaceutical dosage form. Chromatographic separation was achieved on a polar Waters ACQUITY BEH phenyl 100 × 2.1 mm, 1.7-μm column using the gradient program consisting of mobile phase A: 0.03 M sodium perchlorate with 0.002 M of 1-octanesulfonic acid sodium salt (pH 2.5 buffer) and mobile phase B: 0.03 M sodium perchlorate with 0...
August 28, 2018: Journal of Chromatographic Science
Zoe Ramos, Gabriel A Rothbauer, Johnathan Turner, Corbin Lewis, Kevin Morris, Eugene Billiot, Fereshteh Billiot, Yayin Fang
In this study the chiral selectivity of l-undecyl-leucine (und-leu) for binapthyl derivatives was examined with the use of arginine and sodium counterions at pH's ranging from 7 to 11. The objective of this project was to investigate whether a cationic amino acid, such as arginine would achieve enhanced chiral selectivity when utilized as the counterion in the place of sodium in micellar electrokinetic chromatography. The data indicate that und-leu has significantly improved chiral selectivity toward 1,1'-binaphthyl-2,2'-diyl hydrogenphosphate (BNP) enantiomers in the presence of arginine counterions in comparison to sodium and that, at least in the case of this study, the enantiomeric form of the arginine did not appear to play a role in the chiral selectivity...
August 28, 2018: Journal of Chromatographic Science
Hariram Balasubramanian, R Suresh Kumar, Jaya Shree Anireddy, Dama Veugopala Rao
A simple reverse phase method for the selective quantification of ezetimibe (EZM), its diastereomers and other related substances was developed. The method demonstrated an excellent separation between each of the 14 impurities (including diastereomers, specified impurities and degradation products) and EZM within a runtime of 45 min. The developed method was evaluated against the reported USP method, other literature methods found that none of them was able to separate/show the absence of all the diastereomers and degradation products...
August 25, 2018: Journal of Chromatographic Science
Rifat Emre Burmaoglu, Serap Saglik Aslan
A method has been developed and validated for analysis of zoledronic acid (ZOL) and its related substances by ion-pair reversed-phase high performance liquid chromatography with evaporative light scattering detection (ELSD). Chromatographic separation was achieved with gradient elution by using a C18 column, mobile phase containing 12 mM ammonium acetate buffer and 35 mM n-pentylamine, whose pH value is 7.0, and 5% acetonitrile. The mobile-phase flow rate was 1.0 mL/min. The calibration plot was linear in the range from 0...
August 25, 2018: Journal of Chromatographic Science
A Doganay, B Koksel, S O Gundogdu, Y Capan
The pharmaceutical combination of dexpanthenol (DPA), lidocaine hydrochloride (LIH) and mepyramine maleate (MAM) is used for their anti-allergic, anti-inflammatory, anti-pruritic, anesthetic and antiseptic properties. The present study was aimed to develop and validate a new, first and rapid high performance liquid chromatographic method for simultaneous determination of DPA, LIH and MAM in the presence of their stress-induced degradation products in pharmaceutical gel/fluigel formulations. The chromatographic separation was performed on an Inertsil ODS-3 V, 250 × 4...
July 31, 2018: Journal of Chromatographic Science
Simin Khodaei, Samira Ghaedmohammadi, Mehdi Mohammadi, Garshasb Rigi, Parisa Ghahremanifard, Reza Zadmard, Gholamreza Ahmadian
High-affinity ligands, such as protein A, can be used to develop biocompatible matrices for antibody purification. In this paper, two methods were used for immobilization of protein A on the chitosan. In the first approach, amino groups of chitosan beads were functionalized with tris(2-aminoethyl)amine to produce amine double-branched moieties, which were subsequently activated with glutaraldehyde. In the second approach, chitosan beads were directly modified by glutaraldehyde to produce aldehyde groups. Structural characterization and successful modification of the functional groups on the supports were confirmed by scanning electron microscopy, FTIR spectroscopy and elemental analysis...
July 31, 2018: Journal of Chromatographic Science
Qing Ye, Zongbao Chen
In this work, a new method was developed for perfluorinated compounds (PFCs) analysis in water samples based on decyl-perfluorinated magnetic mesoporous nanocomposites microspheres-assisted extraction and microwave-assisted derivatization followed by gas chromatography-mass spectrometry analysis. The decyl-perfluorinated magnetic mesoporous nanocomposites have several advantages such as fast separation ability, good dispersibility in water sample and high selective preconcentration of PFCs. Various parameters, including eluting solvent and volume, the amounts of absorbents, extraction time and elution time, the microwave-assisted derivatization conditions were optimized...
July 31, 2018: Journal of Chromatographic Science
Judyta Hejniak, Irena Baranowska, Sandra Stencel, Sylwia Bajkacz
A study of the simultaneous separation and determination of selected polyphenols (rutin, narirutin, naringin, hesperidin, neohesperidin, quercetin, naringenin, kaempferol and hesperetin) with reported effects in the treatment of depression and cardiac and neurodegenerative diseases was performed. An RP-ultrahigh-performance liquid chromatography (UHPLC)-ultraviolet method for analyte separation and determination was successfully developed and validated for a ZORBAX Eclipse Plus C18 RRHD analytical column. Separation was carried out in gradient elution mode with acetonitrile and water modified with 0...
July 31, 2018: Journal of Chromatographic Science
Thyagarajan Shanmugam, Joseph Selvaraj, Surendiran A
Arsenic exists in the form of various chemical species differing in their physicochemical behavior, toxicity, bioavailability and biotransformation. The determination of arsenic species is an important issue for environmental, clinical and food chemistry. However, differentiation of these species is a quite complex analytical task. Numerous speciation procedures have been studied that include electrochemical, chromatographic, spectrometric and hyphenated techniques. Ion exchange chromatography is one of the techniques used to speciate inorganic arsenic i...
July 31, 2018: Journal of Chromatographic Science
Yang Wang, Li Ma, Mengliu Zhang, Meiwan Chen, Peng Li, Chengwei He, Chunyan Yan, Jian-Bo Wan
Retention time (RT) shifts are inevitable in liquid chromatography-mass spectrometry (LC-MS)-based metabolomics studies. RT alignment, aligning peaks originating from the same feature to an identical RT, is a necessary step prior to multivariate data analysis. Many RT alignment software packages and various algorithms have been developed. In the present study, a simple method for peak alignment was proposed using relative RT related to an inherent peak in the chromatogram, and its performance on RT alignment in untargeted metabolomics was evaluated using an LC-MS dataset acquired from plasma samples from osteoporotic rats, and compared with the common MarkerLynx XS method using different RT window...
July 31, 2018: Journal of Chromatographic Science
Ying Shi, Yanqin Zhong, Aimin Sun, Bo Gao, Chengjun Sun, Jingyuan Xiong
A rapid and simple high-performance liquid chromatography/electrospray ionization tandem mass spectrometry method was developed for simultaneous analysis of 15 key chemicals in slimming foods and herbal products. These chemicals were strictly restricted adulterants (phenolphthalein, sibutramine, fenfluramine, clopamide, ephedrine, norpseudoephedrine, caffeine and phenformin) and physiologically relevant active components (l-carnitine, nuciferine, aloe-emodin, rhein, emodin, chrysophanol and physcion). In multi-day validations, intra- (n = 5) and inter-day precision (n = 3), limits of detection and limits of quantification for all analytes were 0...
July 12, 2018: Journal of Chromatographic Science
Changjie Hu, Hanqiao Zhang, Menglin Zhang, Zhiyuan Mi, Jun Wang, Wenpin Lu, Jiangtao Su
During the synthesis of abiraterone acetate bulk drug in some laboratory batches, two unreported impurities were detected by high-performance liquid chromatography analysis at levels ranging from 0.05 to 0.10% according to the United States Pharmacopeia method. The structures of two impurities were characterized and confirmed by NMR and MS, which were proposed to be [3β-acetoxy-16-(3β-acetoxy-androsta-5,16-dien-17-yl)-17-(3-pyridyl)-androsta-5,16-di-ene] and [3β-acetoxy-16-(3β-acetoxy-androsta-5,16-dien-17-yl)-17-androsta-5,16-di-ene]...
July 11, 2018: Journal of Chromatographic Science
Martin Kertys, Anna Urbanova, Juraj Mokry
Phosphodiesterases are known as a super-family of 11 isoenzymes, which can exert various functions based on their organ distribution. In this work, a rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method was developed for quantification of tadalafil (phosphodiesterase five inhibitor), roflumilast (RF) (phosphodiesterase four inhibitor) and its active metabolite, RF N-oxide in guinea pig plasma. Chromatographic separation was carried out on UPLC BEH C18 column (2.1 mm × 50 mm, 1...
July 10, 2018: Journal of Chromatographic Science
Ishit R Kothari, Kishan S Italiya, Saurabh Sharma, Anupama Mittal, Deepak Chitkara
Combinational drug delivery successfully merges the benefits of nanotechnology and combination therapy by providing diversity to improve the carrier properties and better control over tailoring them as per the need of cancer treatment. A combination of conventional chemotherapeutic agent; docetaxel (DTX) and antioxidant agent; alpha lipoic acid (ALA) which acts by preventing metastasis may fulfill idealness of control and targeted drug delivery against breast cancer. The objective of the current study is to develop a reverse-phase HPLC-UV method for simultaneous determination of DTX and ALA in lipid-based nanoformulations...
July 10, 2018: Journal of Chromatographic Science
Amira M El-Kosasy, Omar Abdel-Aziz, Miriam F Ayad, Ola M Mabrouk
Gradient reversed-phase high-performance liquid chromatography with photodiode array detection was used for separation, detection and quantification of bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, namely, BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl in pure form and in canned foods, where canned beans and tuna were used as representatives of aqueous and oil-in-water food matrices, respectively. The proposed method had a linear range of 0.01-0.5 μg g-1 for BADGE·HCl·H2O, BADGE·H2O, BADGE·2HCl and 0...
July 6, 2018: Journal of Chromatographic Science
Wenyan Chen, Shijuan Zhang, Jinmao You, Zhi Chen, Mingbo Yue
The extraction and analysis of free fatty acids (FFAs) in the whole natural plants are reported. The aminopropyl-functionalized SBA-15 was designed to increase the efficiency of the matrix solid-phase dispersion (MSPD) extraction method. MSPD extraction was performed using to extract FFAs via acid-base interactions. The optimum parameters for the MSPD extraction were N-SBA-15 30 mg, grinding time 120 s and elution solvent methanol-HCl (6:4, v/v). After extraction, the FFAs were analyzed by HPLC with fluorescent labeling...
July 6, 2018: Journal of Chromatographic Science
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