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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
Chen-Xiao Shan, Shu-Chen Guo, Sheng Yu, Ming-Qiu Shan, Sam Fong Yau Li, Chuan Chai, Xiao-Bing Cui, Li Zhang, An-Wei Ding, Qi-Nan Wu
Leaves of Platycladus orientalis have been used as blood cooling and homeostatic therapy for thousands of years in traditional Chinese medicine. Emerging evidences of modern pharmacology have proved flavonoids as the key elements responsible for the efficacies. However, there has been no report on pharmacokinetic study of the flavonoids from Platycladus orientalis leaves extract. In this study, a sensitive and rapid ultra-flow liquid chromatography-tandem mass spectrometry method was established and validated for the simultaneous determination of amentoflavone, afzelin, hinokiflavone and quercitrin in rat plasma...
July 6, 2018: Journal of Chromatographic Science
Ch Gangu Naidu, R Nageswara Rao, A V Prasada Rao, K Nagesh Kumar, Raju Padiya, V Madhusudhan Rao
A sensitive, selective rapid bioanalytical assay method was developed and quantification of iloperidone (ILP) and olanzapine (OLZ) in rat plasma was done by mass spectrometry. Systematic sample preparation and extraction procedure were carried out by supported liquid extraction using dichloromethane to extract both the eluents (ILP and OLZ) from rat plasma samples. The extorted samples were injected on a selective Waters XTerra® C18 reverse-phase bonded column (250 × 4.6 mm i.d., 5 μm) using acetonitrile and 15 mM ammonium formate containing 0...
July 6, 2018: Journal of Chromatographic Science
Eglal A Abdelaleem, Ibrahim A Naguib, Shimaa A Farag, Hala E Zaazaa
Two simple, rapid chromatographic methods were developed for the simultaneous determination of Theophylline (THP), Guaifenesin (GUI) and Guaifenesin impurity namely Guaiacol (GUA). The first method is an isocratic reversed-phase high-performance liquid chromatography (RP-HPLC) method, where separation of THP, GUI and GUA was achieved on C18 column using methanol:water (containing 0.1% triethylamine):acetonitrile (30:60:10, by volume) as a mobile phase with a flow rate of 0.7 mL /min and UV detection at 275 nm...
June 30, 2018: Journal of Chromatographic Science
Mohamed Nadjib Rebizi, Khaled Sekkoum, Nasser Belboukhari, Abdelkrim Cheriti, Hassan Y Aboul-Enein
The enantioseparation of three fluoroquinoline antibacterial drugs, namely, flumequine, ofloxacin and lomefloxacin using high-performance liquid chromatography was optimized on seven polysaccharide-derived chiral stationary phases, namely, Chiralpak® IB, chiralpak® IA, Chiralpak® AD, Chiralcel® OJ, Chiralcel® OD, Chiralcel® OD-H and Chiralcel® OZ-3 and applying different mobile phases in isocratic mode is described. The role of addition of organic additives was also investigated. A baseline separation of flumequine, ofloxacin and lomefloxacin enantiomers was achieved...
June 21, 2018: Journal of Chromatographic Science
Jair Sebastião Silva Pinto, Lívia Mari Assis, Mariane Aissa Andrade, Fernando Mauro Lanças
This work reports a study on the use of Pressurized Liquid Extraction (PLE) for the selective extraction of organic compounds (aliphatic hydrocarbons - AHs, polycyclic aromatic hydrocarbons - PAHs and polycyclic aromatic compounds - PACs) from high-ash Brazilian coal. A homemade PLE system was built and solvents of different polarities (hexane, toluene and ethanol) were employed to extract the organic compounds from coal samples at a pressure of 10 MPa, under temperatures of 80°C and 200°C and extraction times up to 120 min...
June 21, 2018: Journal of Chromatographic Science
Mutaz E Salih, Ahmad Aqel, Babiker Y Abdulkhair, Zeid A ALOthman, Mohamad A Abdulaziz, A Yacine Badjah-Hadj-Ahmed
Recently, analytical separation techniques have the potential toward green approaches to reduce the environmental impact. This study focuses on the development of an analytical method for the determination of paracetamol and chlorzoxazone in their pharmaceutical combination. The separation was achieved using a home-made capillary column (0.10 mm i.d. × 200 mm length) filled with porous cross-linked hexyl polymethacrylate as monolithic stationary phase. The method proved to be simple, fast, sensitive, efficient, cost-effective and green approach due to the combination of the amazing properties of a monolithic material and a miniaturized liquid chromatography, which would be considered as a step toward reducing the analytical costs and the environmental impact of chromatographic applications...
June 16, 2018: Journal of Chromatographic Science
Amber Thaxton-Weissenfluh, Tarek S Belal, Jack DeRuiter, Forrest Smith, Younis Abiedalla, Logan Neel, Karim M Abdel-Hay, C Randall Clark
The indole ring regioisomeric methoxy-1-n-pentyl-3-(1-naphthoyl)-indoles represent indole ring-substituted analogs of the synthetic cannabinoid JWH-018. The electron ionization mass spectra show equivalent regioisomeric major fragments resulting from cleavage of the groups attached to the central indole nucleus. The characteristic (M-17)+ fragment ion at m/z 354 resulting from the loss of OH group is significant in the mass spectra of all four compounds. Fragmentation of the naphthoyl and/or pentyl groups yields the cations at m/z 314, 300, 244 and 216...
June 16, 2018: Journal of Chromatographic Science
Meiyun Shi, Xiaojun Zhao, Tingting Wang, Lei Yin, Yanyan Li
In this study, a novel and high-throughput liquid chromatography-tandem mass spectrometric (LC-MS-MS) assay was developed and validated for simultaneous determination of two glycopeptides (vancomycin, teicoplanin) and two small molecule compounds (meropenem, voriconazole) in human plasma. Only 50 μL of human plasma is used to quantify these four drugs simultaneously at clinical concentration levels. After a relative simple protein precipitation, the supernatant was then diluted with mobile phase acetonitrile: 0...
June 14, 2018: Journal of Chromatographic Science
Bhargav Patel, Arvind G Jangid, B N Suhagia, Nirmal Desai
An isotope dilution selective and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) method has been developed for the simultaneous determination of hydrochlorothiazide (HCTZ) and ramipril in human plasma through a new concept of periodical polarity switching. Extraction of HCTZ, ramipril and their deuterated analogs as internal standards (ISs) was carried out from 150 μL of human plasma by solid-phase extraction method. Chromatographic separation of analytes was performed on Hypurity C18 (150 mm × 4...
June 12, 2018: Journal of Chromatographic Science
Solomon K S Amoah, Maique W Biavatti
The leaves of the aromatic neotropical shrub Hedyosmum brasiliense are employed popularly as a sedative, aphrodisiac and as a substitute for green tea. Sesquiterpene lactones and phenolic compounds were characterized as the main compounds of its aqueous extract, and some biological investigation demonstrated its anxiolytic, antidepressant and hypnotic effects. The quantification of podoandin, onoseriolide and rosmarinic acid in its infused tea was achieved by means of ultra high performance liquid chromatography coupled to a electronspray ionization interface and a high resolution mass detector...
June 12, 2018: Journal of Chromatographic Science
Sara Maleki, Payman Hashemi, Fahimeh Rasolzadeh, Saba Maleki, Ali Reza Ghiasvand
SBA-15 and MCM-41 nanoporous silica sorbents were synthesized and functionalized by amine groups and used, for the first time, for packing a needle trap device (NTD). The characteristics of the synthesized SBA-15 and MCM-41 sorbents were investigated by X-ray diffraction, scanning electron microscopy and Fourier transfer infrared spectroscopy. The NTD coupling to gas chromatography with a flame ionization detector (GC-FID) was carried out to extract and determine polycyclic aromatic hydrocarbons (PAHs) in contaminated soil samples...
June 12, 2018: Journal of Chromatographic Science
Ádám Tölgyesi, Anupam Giri, Eniko Barta, Thomas J McDonald, Virender K Sharma
The application of thyreostats in livestock has been banned in the European Union since 1981, but these drugs are currently in the focus due to the natural occurrence of thiouracil (TU). Studies have been published on TU contamination in urine samples of animal and human origins without any drug administration of it. This paper presents new analytical methods to analyze thyreostats to support the legislation on the recommended concentration (RC) levels of these drugs. Both screening and confirmatory methods are developed for analyzing thyreostats in porcine and bovine urines using a liquid chromatography-tandem mass spectrometry technique...
June 6, 2018: Journal of Chromatographic Science
Mei Zhang, Yong Zhang, Siqi Ren, Zunjian Zhang, Yongren Wang, Rui Song
A method for monitoring l-asparagine (ASN) depletion in patients' serum using reversed-phase high-performance liquid chromatography with precolumn o-phthalaldehyde and ethanethiol (ET) derivatization is described. In order to improve the signal and stability of analytes, several important factors including precipitant reagent, derivatization conditions and detection wavelengths were optimized. The recovery of the analytes in biological matrix was the highest when 4% sulfosalicylic acid (1:1, v/v) was used as a precipitant reagent...
June 6, 2018: Journal of Chromatographic Science
Vinod K Ahirrao, Vipul P Rane, Kiran R Patil, Vijay J Patil, Ravindra D Yeole, Mahesh V Patel
A highly stereo-specific liquid chromatographic method was developed and validated for the quantification of enantiomeric impurity (R-enantiomer) in novel oxazolidinone antibacterial agent (WCK 4086), a drug substance. The separation was achieved on Chiralpak AD-H (amylose-based chiral stationary phase) using a mobile phase consisting of n-hexane:2-propanol:methanol:trifluoroacetic acid (80:10:10:0.4, v/v/v/v) at a flow rate of 1.0 mL min-1. Chromatographic resolution between two enantiomers was found to be more than 2...
May 30, 2018: Journal of Chromatographic Science
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