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Journal of Chromatographic Science

Chunqin Mao, Yaping Zhou, De Ji, Xuanzhong Tan, Yi Tao, Wenyi Zang, Tulin Lu
To develop a method to overall evaluate the quality of Dachaihu Granule (DCHG), high-performance liquid chromatography coupled with diode array detector was used to establish chemical fingerprint of DCHG. The correlation between the formula and its raw herbs was also evaluated. According to the retention time of standard components, chemical fingerprint of DCHG was developed and a total of 21 constituents were characterized. The separation was performed on a Kromasil C18 column (250 mm × 4.6 mm i.d. with 5...
January 17, 2017: Journal of Chromatographic Science
Youwei Yu, Zhefeng Fan
An efficient magnetic sorbent of laccaic acid-loaded magnetite nanocomposite was successfully synthesized for extraction and preconcentration of tetracyclines (TCs) from bovine milk sample. The synthesized nanocomposite was characterized by scanning electron microscopy and Fourier transform-infrared spectroscopy. Determination of the extracted TCs was performed by high performance liquid chromatography. Parameters affecting the efficiency of magnetic solid-phase extraction were studied and optimized. The best adsorption conditions were 80 mg of sorbent, 50 mL of sample volume, pH 7, 45°C and 20 min; the elution conditions were 0...
January 10, 2017: Journal of Chromatographic Science
Guo-Ning Chen, Ning Li, Tian Luo, Yu-Ming Dong
In this study, 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), a bifunctional group compound, was used as a single cross-linking agent to prepare molecular imprinted inorganic-organic hybrid polymers by in situ polymerization for open-tubular capillary electro chromatography (CEC) column. The optimal preparation conditions were: the ratio between template molecule and functional monomer was 1:4; the volume proportion of porogen toluene and methanol was 1:1 and the volume of cross-linking agent γ-MPS was 69 μL...
January 10, 2017: Journal of Chromatographic Science
Yao Wang, Yuan Liu, Qi Wu, Xin Yao, Zongqi Cheng
An accurate, precise and sensitive ultra-performance liquid chromatography tandem mass spectrometric (UPLC-MS-MS) method was developed for the determination of flavonoids, terpene lactones, together with ginkgolic acids in Ginkgo biloba leaves extract (EGb 761). This is the first report of the simultaneous analysis of major active ingredients and toxic components in EGb 761 using UPLC-MS-MS. This analysis afforded good linearity, precision, repeatability and accuracy. In addition, the content of those major bioactive components in EGb 761 prepared by different manufacturers of China was determined to establish the effectiveness of the method...
January 8, 2017: Journal of Chromatographic Science
A P Dewani, A S Tripathi, P G Shelke, R L Bakal, D S Mohale, A V Chandewar
A novel, simple and mass spectrometry (MS) compatible high-performance liquid chromatography (HPLC) method is reported for the simultaneous estimation of ilaprazole (ILA) and glimepiride (GLM) in rat plasma. The bio-analytical procedure involves extraction of ILA, GLM and internal standard (IS) from rat plasma with a solid-phase extraction (SPE) process. The chromatographic analysis was performed on Waters-600 system using an isocratic mobile phase comprising methanol:water (80:20 % v/v) with pH of water modified to three using formic acid at a flow rate of 1...
January 8, 2017: Journal of Chromatographic Science
Jialin Qu, Xinjia Yan, Chunyan Li, Jing Wen, Chongning Lu, Jungang Ren, Ying Peng, Shaojiang Song
A multi-component quantification fingerprint based on high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry technique has been established for the comparative analysis of raw and ripe fruits of Forsythia suspensa originated from different provinces. Eighteen bioactive constituents including three phenylethanoid glycosides derivatives, six phenolic acids, three flavonoids, four phenylpropanoids, one fatty acid and one terpenoid were identified and quantified. Total contents of phenylethanoid glycosides, phenylpropanoids and flavonoids from raw samples were found much higher than those from ripe samples, while total content of phenolic acids showed a contrary tendency...
January 8, 2017: Journal of Chromatographic Science
Yu Kong, Guifang Yang, Linghong Kong, Zhanwu Hou, Guifang Yang, Hua Li, Xiaoying Ji, Meili Gao
Both reduced and oxidized forms of glutathiones were firstly stacked and detected using pH-mediated acid stacking method, in which glutathiones were stacked as cations and separated as anions. Factors, such as injection time, sweeping time, buffer pH, concentration of sodium chloride in sample matrix, that influenced stacking and separation were systematically studied and optimized. Under the optimum condition, the enhancement factors of ~20 times for both reduced and oxidized forms of glutathiones could be easily obtained within 20 min with satisfied sensitivities (limit of detections were 0...
December 29, 2016: Journal of Chromatographic Science
Ioana Ionuţ, Brînduşa Tiperciuc, Ovidiu Oniga
The lipophilic character of 20 previously reported compounds-derivatives of N(1)-arylidene-thiosemicarbazone (series A: ) and their corresponding 1,3,4-thiadiazolines (series B: )-has been determined by reversed-phase thin-layer chromatography, using i-propanol-water mixtures as eluents. Principal component analysis (PCA) allowed an objective estimation of the retention behavior of the tested compounds and also afforded to obtain a 2D scatterplot, described by the first two principal components, which had the effect of separating the compounds from each other most effectively...
December 29, 2016: Journal of Chromatographic Science
Jin Guan, Jie Min, Feng Yan, Wen-Ya Xu, Shuang Shi, Si-Lin Wang
A new gas chromatographic method for the simultaneous determination of six organic residual solvents (acetonitrile, tetrahydrofuran, ethanol, acetone, 2-propanol and ethyl acetate) in azilsartan bulk drug is described. The chromatographic determination was achieved on an OV-624 capillary column employing programmed temperature within 21 min. The validation was carried out according to International Conference on Harmonization validation guidelines. The method was shown to be specific (no interference in the blank solution), sensitive (Limit of detection can achieve 1...
December 23, 2016: Journal of Chromatographic Science
Josephine Al-Alam, Laura Bom, Asma Chbani, Ziad Fajloun, Maurice Millet
A simple method combining ion-pair methylation, high-performance liquid chromatography (HPLC) analysis with detection at 272 nm and atomic absorption spectrometry was developed in order to determine 10 dithiocarbamate fungicides (Dazomet, Metam-sodium, Ferbam, Ziram, Zineb, Maneb, Mancozeb, Metiram, Nabam and Propineb) and distinguish ethylenbisdithiocarbamates (EBDTCs) Zineb, Maneb and Mancozeb in diverse matrices. This method associates reverse phase analysis by HPLC analysis with detection at 272 nm, with atomic absorption spectrometry in order to distinguish, with the same extraction protocol, Maneb, Mancozeb and Zineb...
December 19, 2016: Journal of Chromatographic Science
J Flieger, M Tatarczak-Michalewska, E Blicharska, R Świeboda, T Banach
Reversed-phase high-performance liquid chromatography assay with the diode array detector was applied for detection of trans-resveratrol complexes with copper (II). Two complexes with copper to resveratrol ratio 3:2 and 1:1 were identified in ethanolic-aqueous solutions in neutral and acidic conditions. The matrix-assisted laser desorption ionization-time of flight mass spectrometry was used for evaluation of complexes in eluate liquid fraction. The structures of complexes were modeled by Titan, Spartan and HyperChem software...
December 19, 2016: Journal of Chromatographic Science
Mingming Zhao, Ti Zhang, Guofei Li, Feng Qiu, Yaxin Sun, Limei Zhao
A specific and sensitive Ultra-high Performance Liquid Chromatography-tandem Mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of the concentrations of valproic acid (VPA) and its clinically relevant metabolites (4-ene-VPA, 2,4-diene-VPA and 2-ene-VPA) in human serum. After solid-phase extraction, VPA, its metabolites and the internal standard were subjected to chromatographic separation by gradient elution of acetonitrile and 10 mM ammonium acetate as mobile phase at a flow rate of 0...
December 19, 2016: Journal of Chromatographic Science
Mariana R Gama, Pankaj Aggarwal, Kun Liu, Milton L Lee, Carla B G Bottoli
Capillary columns containing butyl or lauryl methacrylate monoliths were prepared using two different free-radical polymerization methods: conventional free-radical polymerization and controlled/living free-radical polymerization, both initiated thermally, and these methods were compared for the first time. Both monolith morphology and chromatographic efficiency were compared for the synthesized stationary phases using scanning electronic microscopy (SEM) and capillary liquid chromatography, respectively. Columns prepared using controlled method gave better chromatographic performance for both monomers tested...
December 19, 2016: Journal of Chromatographic Science
Maya S Eissa, Osama I Abd El-Sattar
Loxoprofen sodium (LOX) is a recently developed novel propionic acid derivative. Owing to its instability under both hydrolytic and oxidative conditions, the development of simple, rapid and sensitive methods for its determination in the presence of its possible forced degradation products becomes essential. Two simple chromatographic methods, high-performance thin layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC), were developed associated with ultraviolet (UV) detection. In HPTLC-densitometric method, the separation of LOX from its degradation products was achieved using silica gel F254 plates and toluene:acetone:acetic acid (1...
December 17, 2016: Journal of Chromatographic Science
H Ecem Yelkenci, Nevin Öztekin
A rapid and sensitive capillary zone electrophoresis method for the simultaneous separation and determination of lanthanide ions, combined with capacitively coupled contactless conductivity detection (C(4)D), is reported. The influence of experimental parameters on separation was investigated. The optimal separation conditions were obtained when 4.5 mM 2-hydroxyisobutyric acid and 1 mM acetic acid (HAc) at pH 4.5 were used as buffer solution. Under these conditions, complete separation of all 14 lanthanide ions was achieved in 6 min...
December 17, 2016: Journal of Chromatographic Science
Sumet Kongkiatpaiboon, Parunkul Tungsukruthai, Kusuma Sriyakool, Kanoktip Pansuksan, Amolnat Tunsirikongkon, Hataichanok Pandith
The HPLC-DAD method was developed to determine morin content in Maclura cochinchinensis Corner heartwood extract. The chromatographic separation was performed using a Hypersil BDS C18 column, isocratic solvent system of 0.5% acetic acid in water:acetonitrile (80:20) with 1.0 mL/min flow rate and detected at 355 nm. The standard curve of morin was linear in the range of 7-905 μg/mL. The method was precise with intra-day relative standard deviation (RSD) of lower than 1% and 2.06% for inter-day RSD. The method accuracy represented by percent recover was 99...
December 14, 2016: Journal of Chromatographic Science
Meng-Zhe Guo, Jie Han, Dan-Dan He, Jia-Hui Zou, Zheng Li, Yan Du, Dao-Quan Tang
Chromatographic separation is still a critical subject for the quality control of traditional Chinese medicine. In this study, three different high performance liquid chromatographic (HPLC) systems employing commercially available columns packed with 1.8, 3.5 and 5.0 μm particles were respectively developed and optimized for the combinative fingerprint analysis and multi-ingredients quantification of Sangju Ganmao tablet (SGT). Chromatographic parameters including the repeatability of retention time and peak area, symmetry factor, resolution, number of theoretical plates and peak capacity were used to assess the chromatographic performance of different HPLC systems...
December 1, 2016: Journal of Chromatographic Science
Ali Mohamed Ali Alsharif, Guan-Huat Tan, Yeun-Mun Choo, Abubakar Lawal
Hollow fiber liquid-phase microextraction (HF-LPME) techniques coupled to chromatographic systems have been widely used for extraction and determination of diverse compounds. HF-LPME was able to provide better results in precision, accuracy, selectivity and enrichment factor, in addition to reduction of matrix effect and carry over. It is applicable within a wide pH range and compatible with most analytical instruments which enable the utilization of HF-LPME in a wide variety of applications. This review focused on the modified HF-LPME techniques, efficiency, comparison to other LPME methods and applications...
November 29, 2016: Journal of Chromatographic Science
Xinjie Sun, Yingqin Wei, Baojuan Hou, Guowei Zhou
A new nanocomposite membrane was used to clean up impurities from complex samples and the obvious synergy was obtained in this paper. The nanocomposite membrane was prepared by dispersing TiO2 nanoparticles in chloroform and filled in the pores and lumen of polyether sulfone membrane fiber. The novel microextraction method showed the ideal selective extraction effect for alkaloids in the formulae composed of Rhizoma coptidis and the excellent clean-up efficiency compared with the single membrane method. The optimum extraction conditions were as follows: chloroform as accepted phase; the number of nanocomposite membrane fiber bars, 7; extraction time, 30 min; pH of the sample solution, 10...
November 29, 2016: Journal of Chromatographic Science
Zhibing Wang, Siyu Ma, Qian Zhang, Shuang He, Qing Li, Jianxue Hu, Hanqi Zhang
A simple, rapid and efficient method based on matrix solid-phase dispersion coupled with high-performance liquid chromatography was developed for determination of lipophilic constituents, including dihydrotanshinone, tanshinone I, cryptotanshinone and tanshinone II A in Salvia miltiorrhiza Bunge Box-Behnken design was employed for optimization of the extraction conditions of matrix solid-phase dispersion, including mass ratio of dispersant to sample, volume of elution solvent, and amount of cleanup reagent...
November 29, 2016: Journal of Chromatographic Science
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