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Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry 被引量:4
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作者 SHAN Xiao Mei SHEN Deng Hui +2 位作者 WANG Bing Shuang LU Bei Bei HUANG Fa Yuan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第6期471-474,共4页
To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry ... To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%. 展开更多
关键词 UPLC BPA Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid phase Extraction and ultra performance liquid chromatography-tandem Mass Spectrometry MASS
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Uncertainty Evaluation of Determination of Microcystin MC-LR in Environmental Samples by Solid Phase Extraction-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry 被引量:1
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作者 Zhao Bin Zhang Min Zhang Fuhai 《Meteorological and Environmental Research》 CAS 2016年第6期54-57,共4页
To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated first... To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated firstly,and the expanded uncertainty was calculated finally.The results show that when MC-LR concentration in the water samples was 0.50 μg/L,the expanded uncertainty was 0.00628 μg/L(k=2). 展开更多
关键词 Uncertainty SOLID phase extraction ultra performance liquid chromatography TANDEM mass SPECTROMETRY MICROCYSTIN MC-LR China
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A Sensitive Reversed-Phase High-Performance Liquid Chromatography Method for the Quantitative Determination of Milk Xanthine Oxidase Activity 被引量:1
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作者 Zhongqin Li Ruizhang Guan Hongwei Liu 《Open Journal of Medicinal Chemistry》 2013年第1期26-30,共5页
A new reversed-phase high performance liquid chromatography method was developed to quantitate the activity of xanthine oxidase involved in milk fat globule membrane with xanthine as the substrate and the separation o... A new reversed-phase high performance liquid chromatography method was developed to quantitate the activity of xanthine oxidase involved in milk fat globule membrane with xanthine as the substrate and the separation of product (uric acid). The increment of uric acid in the reaction system was used to calculate the total activity of XO. The optimized assay conditions, linearity of detection, recovery of uric acid and chromatogram were developed in text, indicating this method is simple, rapid and efficient. It is an alternative potential method for the determination of the activity of XO in milk. 展开更多
关键词 XANTHINE OXIDASE (XO) Enzyme Activity Assay reverseD-phase High performance liquid chromatography (RP-HPLC)
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Simultaneous Determination of Amlodipine with H<sub>1</sub>-Receptor Antagonists by Reversed Phase High Performance Liquid Chromatography and Application to Interaction Studies
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作者 Muhammad Saeed Arayne Najma Sultana +1 位作者 Saima Sher Bahadur Muhammad Nawaz 《American Journal of Analytical Chemistry》 2012年第9期632-637,共6页
A rapid, fast and precise method has been developed and validated for the simultaneous determination of amlodipine with H1-receptor antagonists (cetirizine, fexofenadine, and buclizine) from dosage forms. The chromato... A rapid, fast and precise method has been developed and validated for the simultaneous determination of amlodipine with H1-receptor antagonists (cetirizine, fexofenadine, and buclizine) from dosage forms. The chromatography was performed on a Purospher? Star, C18 (5 mm, 250 × 4.6 mm) column using acetonitrile: buffer (0.01 mM) (40:60, v/v, pH adjusted to 3.0), as a mobile phase. The mobile phase was pumped at a flow rate of 1.0 mL·min-1 and UV detection was performed at 240 nm. The method was validated for linearity, accuracy, precision and specificity. The method was applied to study the interaction between amlodipine and H1-receptor antagonists. These interactions were carried out in simulated gastric juice (pH 1), simulated full stomach (pH 4), blood pH (pH 7.4) and simulating GI (pH 9). The interacting drugs were heated at 37℃ with intermit-tent shaking and the samples were withdrawn every thirty minutes for three hours and drug contents were analyzed by RP-HPLC techniques. In most cases the in vitro availability of amlodipine was decreased. It was observed that the change in in vitro availability was pH dependent. 展开更多
关键词 AMLODIPINE CETIRIZINE FEXOFENADINE Buclizine INTERACTIONS reversed phase High performance liquid chromatography
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Quantitative analysis by reversed-phase high-performance liquid chromatography and retinal neuroprotection after topical administration of moxonidine
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作者 Qian Zhang Mei-Fang Chu +5 位作者 Yan-Hong Li Chun-Hua Li Run-Jia Lei Si-Cen Wang Bao-Jun Xiao Jian-Gang Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第3期390-398,共9页
AIM:To determine moxonidine in aqueous humor and iris-ciliary body by reversed-phase high performance liquid chromatography(RP-HPLC),and to evaluate the retinal neuroprotective effect after topical administration with... AIM:To determine moxonidine in aqueous humor and iris-ciliary body by reversed-phase high performance liquid chromatography(RP-HPLC),and to evaluate the retinal neuroprotective effect after topical administration with moxonidine in a high intraocular pressure(IOP)model.METHODS:The eyes of albino rabbits were administered topically and ipsilaterally with 0.2%moxonidine.A RPHPLC method was employed for the identification and quantification of moxonidine between 2 and 480 min,which presented in the aqueous humor and iris-ciliary body.Flash electroretinography(F-ERG)amplitude and superoxide dismutase(SOD)level were measured between day 1 and day 15 after topical administration with moxonidine in a rabbit model of high IOP.Histological and ultrastructural observation underwent to analyze the changes of retinal morphology,the inner retinal layers(IRL)thickness,and retinal ganglion cell(RGC)counting.RESULTS:Moxonidine was detectable between 2 and 480 min after administration,and the peak concentration developed both in the two tissues at 30 min,0.51μg/m Lin aqueous humor and 1.03μg/g in iris-ciliary body.In comparison to control,F-ERG b-wave amplitude in moxonidine eyes were significantly differences between day 3 and day 15(P<0.01)in the high IOP model;SOD levels were significantly higher at all time-points(P<0.01)with a maximum level of 20.29 U/mgprot at day 15;and RGCs were significantly higher(P<0.05).CONCLUSION:Moxonidine is a viable neuroprotective agent with application to high IOP model.All layers of retina,including RGC layer,retinal nerve fiber layer and INL,are more preserved after moxonidine administration.SOD plays a neuroprotective role in ocular hypertension-mediated RGC death. 展开更多
关键词 reverseD-phase high-performance liquid chromatography MOXONIDINE RETINAL GANGLION cell NEUROPROTECTION superoxide DISMUTASE
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Trace Determination of Tamoxifen in Biological Fluids Using Hollow Fiber Liquid-Phase Microextraction Followed by High-Performance Liquid Chromatography-Ultraviolet Detection
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作者 Amir Kashtiaray Hadi Farahani +2 位作者 Sharareh Farhadi Bertrand Rochat Hamid Reza Sobhi 《American Journal of Analytical Chemistry》 2011年第4期429-436,共8页
The applicability of hollow fiber liquid-phase microextraction (HF-LPME) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was evaluated for the extraction and determination of tamox... The applicability of hollow fiber liquid-phase microextraction (HF-LPME) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was evaluated for the extraction and determination of tamoxifen (TAM) in biological fluids including human urine and plasma. The drug was extracted from a 15 mL aqueous sample (source phase;SP) into an organic phase impregnated in the pores of the hollow fiber (membrane phase;MP) followed by the back-extraction into a second aqueous solution (receiving phase;RP) located in the lumen of the hollow fiber. The effects of several factors such as the nature of organic solvent, compositions of SP and RP solutions, extraction time, ionic strength and stirring rate on the extraction efficiency were examined and optimized. An enrichment factor of 360 along with substantial sample clean up was obtained under the optimized conditions. The calibration curve showed linearity in the range of 1 - 500 ng?mL–1 and the limit of detection was found to be 0.5 ng?mL–1 in aqueous medium. A reasonable relative recovery (≥89%) and satisfactory intra-assay (3.7% - 4.2%, n = 3) and inter-assay (7.5% - 7.8%, n = 3) precision illustrated good performance of the analytical procedure in spiked human urine and plasma samples. 展开更多
关键词 High-performance liquid chromatography-ultraviolet Detection HOLLOW Fiber liquid-phase MICROEXTRACTION Human URINE And Plasma Samples TAMOXIFEN
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Determination of Tetracyclines and Their Epimers in Agricultural Soil Fertilized with Swine Manure by Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry 被引量:10
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作者 ZHENG Wen-li ZHANG Li-fang +2 位作者 ZHANG Ke-yu WANG Xiao-yang XUE Fei-qun 《Journal of Integrative Agriculture》 SCIE CSCD 2012年第7期1189-1198,共10页
A rapid, sensitive and specific ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS) method was developed for the analysis of tetracycline antibiotics, including tetracycline (TC), oxyte... A rapid, sensitive and specific ultra-high-performance liquid chromatography tandem mass spectrometry (UPLC-MS) method was developed for the analysis of tetracycline antibiotics, including tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC) and their 4-epimers (4-epiTCs) in agricultural soil fertilized with swine manure. Soil samples were extracted and cleaned-up with 10 mL EDTA-McIlvaine buffer solution (pH 4.0), then cleaned-up and pre-concentrated using the Oasis MAX cartridge and then eluted with 1 mL solution by mixing formic acid, methanol and water at a ratio of 2:15:83 (v/v/v). The purified samples were separated by an ACQUITY UPLC BEH C18 column using acetonitrile and water containing 0.1% formic acid mobile phase and detected by a single quadrupole MS. The limits of detection for the soil extraction method (LODsoil) ranged from 0.6-2.5 lag kg-~ with recoveries from 23.3-159.2%. Finally, the method was applied to an agricultural field in an area with intensive pig-fattening farming. Tetracyclines were detected in soil from 2.8 to 42.4 μg kg-1 soil. These results demonstrate that soil from swine farms can become severely contaminated with tetracycline antibiotics and their metabolites. 展开更多
关键词 TETRACYCLINES EPIMERS ultra performance liquid chromatography SOIL solid phase extraction
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Determination of Steroid Hormone Residues in Fish Tissues Using Gel Permeation Chromatography and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry 被引量:3
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作者 LI Peipei YAN Zhongyong +3 位作者 SUN Xiumei CHEN Si CHEN Yin ZHANG Xiaojun 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1171-1177,共7页
A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 s... A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues. 展开更多
关键词 ultra performance liquid chromatography-tandem mass spectrometry anabolic hormone gel permeation chromatography fish tissue
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A Rapid Separation and Highly Determination of Paraben Species by Ultra-Performance Liquid Chromatography —Electrochemical Detection 被引量:3
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作者 Maneenuch Chuto Sudkate Chaiyo +1 位作者 Weena Siangproh Orawon Chailapakul 《Detection》 2013年第2期21-29,共9页
In this study, a new technique was developed using rapid ultra-performance liquid chromatography (UPLC)-based separation coupled with electrochemical detection by a boron-doped diamond (BDD) electrode for the detectio... In this study, a new technique was developed using rapid ultra-performance liquid chromatography (UPLC)-based separation coupled with electrochemical detection by a boron-doped diamond (BDD) electrode for the detection and quantification of three commonly used parabens (methylparaben (MP), ethylparaben (EP) and propylparaben (PP)). We aimed to reduce the analysis time by using UPLC coupled with a short reverse phase C 18 monolithic column (25 mm×4.6 mm). Operating the monolithic column at low back-pressure resulted in high flow rates. A mobile phaseconsisting of a 25:75 (v/v) ratio of acetonitrile:0.05 Mphosphate buffer (pH 5) at a flow rate of 2.5 mL·min?1 was used to perform the separation. The amperometric detection with the BDD electrode was found to be optimal and reliably reproducible at a detection potential of 1.5 V vs. Ag/AgCl. Under these conditions, the separation of the three targetanalytes (MP, EP and PP) was achieved in 2 min and was linear within a sample concentration range of 0.1 to 50.0 mg·L?1 (r2 values of 0.9970, 0.9994 and 0.9994 for MP, EP and PP, respectively). This method was successfully applied to determine the concentrations of each parabeninsix real samples with therecoveries ranging from of 80.3% - 98.9% for all three parabensfrom samples spiked at 12, 22 and 32 mg·L?1. Therefore, the proposed method can be used as an alternative rapid and selective method for the determination of paraben levels in real samples. 展开更多
关键词 PARABENS ultra-performance liquid chromatography BORON-DOPED Diamond Electrode
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Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction 被引量:1
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作者 LI Cun-man XIAO Yuan-sheng +3 位作者 XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期392-396,共5页
An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matog... An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products. 展开更多
关键词 Unstable compound Isolation and purification Preparative high performance liquid chromatography Solid-phase extraction Iridoid glucoside
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Chemical Components of Achyranthes bidentata Leaves by Ultra High Performance Liquid Chromatography-Mass Spectrometry 被引量:1
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作者 Haiyang DONG Jinshuo MA Fulin YAN 《Medicinal Plant》 CAS 2019年第4期16-19,共4页
[Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical c... [Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical components of A. bidentata leaves were rapidly analyzed using the ultra high performance liquid chromatography-time of flight-high resolution mass spectrometry (UHPLC-TOF-MS).[Results] Thirty eight chemical compounds were identified in samples of A. bidentata leaves collected from Wen County of Henan Province, in which seven chemical compounds had the relative content higher than 5%, linoleic acid reached 25.7% and inokosterone A reached 13.8%.[Conclusions] A. bidentata leaves contain many kinds of chemical compounds. This study is expected to provide a certain basis for further extraction of linoleic acid and inokosterone A. 展开更多
关键词 Achyranthes bidentata LEAVES ultra high performance liquid chromatography-mass SPECTROMETRY (UHPLC-MS) Chemical components Inokosterone
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Simultaneous Determination of Ultraviolet Absorbers and Antibacterial Agents in Textiles by Ultra-High Performance Liquid Chromatography/Orbitrap High Resolution Mass Spectrometry 被引量:1
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作者 Chengyun Wang Tangtang Xie +2 位作者 Rong Xu Junfeng Lin Lixia Li 《World Journal of Engineering and Technology》 2017年第1期1-18,共18页
This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile sampl... This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile samples in methanol, the solutions were analyzed by ultra-high performance liquid chromotagraphy/orbitrap high resolution mass spectrometry (UPLC/Orbitrap HRMS). It showed that a good chromatographic separation for these target compounds was achieved by a Hypersil GOLD column (100 mm × 2.1 mm × 1.9 μm) with a gradient elution of methanol and 0.1% aqueous formic acid solution (containing 0.5 mmol/L ammonium acetate). Triclosan and 4-chloro-3,5-dimethyl phenol (PCMX) were detected by the orbitrap HRMS in an electrospray ionization (ESI) negative mode while the other twelve target compounds were detected by orbitrap HRMS in ESI positive mode. Full scan experiment was performed over the range from m/z 100 to m/z 500. These target compounds were routinely detected with mass accuracy below 2 × 10-6 (2 ppm) at the optimized conditions. The results showed that the limits of detection (LODs) were in the range from 0.1 to 0.3 μg/kg. The blank samples were spiked at three levels and their average recoveries varied from 80.5% to 96.3% while the relative standard deviation (RSD) changed from 3.2% to 9.9%. The present method was also applied for the determination of those ultraviolet absorbers and antibacterial agents in the commercial textiles. 展开更多
关键词 ultra-High performance liquid chromatography/Orbitrap High Resolution Mass Spectrometry Benzotriazoleultraviolet ABSORBERS Isothiazolinone Tric-losan 4-Chloro-3 5-Dimethyl Phenol
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THYMINE BONDED-STATIONARY PHASE FOR HIGH PERFORMANCE LIQUID CHROMATOGRAPHY
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作者 Tao ZHU Qin Wei WANG Lian Zhu SHEN Cheng Xun LU Yi Liang SUN (Department of Chemistry,Peking University,Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期545-548,共4页
A new type of HPLC stationary phase containing thymine derivative was successfully prepared.It was found to give selective separation of nucleic acid bases and several purine derivatives,such as caffeine and theophyll... A new type of HPLC stationary phase containing thymine derivative was successfully prepared.It was found to give selective separation of nucleic acid bases and several purine derivatives,such as caffeine and theophylline.The retention behaviour and elution order of the solutes were interpreted in terms of molecular structure. 展开更多
关键词 TPA NH THYMINE BONDED-STATIONARY phase FOR HIGH performance liquid chromatography
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Development of a Fast and Facile Analytical Approach to Quantify Radiometabolites in Human Plasma Samples Using Ultra High Performance Liquid Chromatography
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作者 cile Malherbe +4 位作者 Rudy Bidault Claude Netter Denis Guilloteau Johnny Vercouillie Nicolas Arlicot 《American Journal of Analytical Chemistry》 2019年第5期185-201,共17页
Introduction: Conventional metabolite analyses often require manual sample preparation, generating variability of measurements. This study describes a new method to quantify radiometabolites in blood, combining ultra ... Introduction: Conventional metabolite analyses often require manual sample preparation, generating variability of measurements. This study describes a new method to quantify radiometabolites in blood, combining ultra high performance liquid chromatography (UHPLC) and turbulent flow chromatography, an alternative fully automated process allowing analyte’s extraction. Methods: A new radiotracer for dopamine transporter imaging, namely LBT-999, was used to demonstrate the method’s robustness. Matrix effect, Turboflow column loading, linearity, specificity and precision were evaluated with in vitro samples of LBT-999 in human plasma. Radiodetector sensitivity and preliminary evaluation were respectively determined by analysis of calibrated samples of [18F]LBT-999 and blood samples from 4 healthy subjects injected with [18F]LBT-999, withdrawn at 5, 15, 30 and 45 min pi. Results: With three sequential loadings (3 × 100 μL) of the Turboflow column, mean coefficients of variation were 1%, below 2%, 2% and 30.9% for matrix effect, specificity, repeatability and intermediate precision, respectively. Correlation coefficients for linearity were superior to 0.97. Limits of detection and quantification of the radiodetector were fixed at 3 and 9 c/s. Retention times for [18F]LBT-999 and the two radiometabolites detected by radio-UHPLC were 6.5, 4.8 and 9.6 min. Forty-five min after the injection, parent fraction was still predominant with 57.8% ± 25% of the total radioactivity. Conclusions: An innovative approach, allying UHPLC and Turboflow column, was developed and its sensitivity, linearity, specificity and repeatability validated. Preliminary results of the clinical trial are in accordance with literature data, demonstrating its efficiency in radiometabolites quantification. 展开更多
关键词 Radiometabolite ultra High performance liquid chromatography Turboflow Method Validation [18F]LBT-999
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Determination of seven active components in Salvia miltiorrhiza herb by matrix solid phase dispersion combined with ion liquid extraction followed by high performance liquid chromatography
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作者 Bo Hong Yanping Wang +1 位作者 Yinglong Han Wenjing Li 《Asian Journal of Traditional Medicines》 CAS 2021年第2期83-97,共15页
A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet de... A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet detection(UV)is proposed,and it was applied to determine the seven active compounds in Salvia Miltiorrhiza herb.SGSIL and ionic liquid[BMIM]BF4 were used as the adsorbent and the green elution reagent in the MSPD procedure.Several extraction conditions including type of filler and elution solvent,the volume of elution solvent,material liquid ratio were optimized.Under the optimum conditions,the SGSIL-MSPD-HPLC method showed a low limit of detection(LOD,S/N=3)of 0.0122-0.8788μg/mL for standard solution,limit of quantification(LOQ,S/N=10)of 0.0406-2.9292μg/mL for standard solution,wide linear range from 1.56 to 2000μg/mL for all compounds for standard solution,correlation coefficients(r)of more than 0.9990,acceptable reproducibility(relative standard deviations,RSDs<3.54%),and precision of RSDs<3.36%for intra-day,RSDs<3.50%for inter-day.The satisfactory recoveries ranged from 96.4 to 102.5,with RSDs less than 3.45%.The developed SGSIL-MSPD method is easier and more suitable for the determination of the seven active compounds in Salvia Miltiorrhiza herb than the traditional ultrasonic extraction.It was an effective and efficient method for the extraction and quantification of the seven active compounds in traditional Chinese herbal samples. 展开更多
关键词 high performance liquid chromatography(HPLC) silica gel supported ionic liquid(SGSIL) matrix solid phase dispersion(MSPD) Salvia miltiorrhiza(SM) DETERMINATION
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Porous Monoliths: Stationary Phases of Choice for High Performance Liquid Chromatography in Various Formats
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作者 SVEC Frantisek 《色谱》 CAS CSCD 北大核心 2005年第6期585-594,共10页
Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography(HPLC) in classical columns in the early 1990s and later extended to the capillary format.These... Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography(HPLC) in classical columns in the early 1990s and later extended to the capillary format.These monolithic materials are prepared using simple processes carried out in an external mold(inorganic monoliths) or within the confines of the column(organic monoliths and all capillary columns).These methods afford macroporous materials with large through-pores that enable applications in a rapid flow-through mode.Since all the mobile phase must flow through the monolith,the convection considerably accelerates mass transport within the monolithic separation medium and improves the separations.As a result,the monolithic columns perform well even at very high flow rates.The applications of monolithic capillary columns are demonstrated on numerous separations in the HPLC mode. 展开更多
关键词 塑料制品 多孔渗水性 固相 硅土 聚合物 合成方法
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Determination of thyreostats in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry
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作者 Lech RODZIEWICZ Jolanta MASLOWIECKA +1 位作者 Anna SADOWSKA Halina CAR 《色谱》 CAS CSCD 北大核心 2017年第10期1048-1054,共7页
Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC... Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine. 展开更多
关键词 ultra-high performance liquid chromatography-tandem mass SPECTROMETRY (UHPLC-MS/MS) thyreostats (TSs) URINE
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Rapid Determination of Three Kinds of Microcystins in Environmental Water Samples by Disk SPE-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry
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作者 Zhao Bin Zhang Min Zhang Fuhai 《Meteorological and Environmental Research》 CAS 2016年第5期62-64,68,共4页
A method of rapidly detecting three kinds of microcystins( MCs) in environmental water samples by using disk SPE- ultra high performance liquid chromatography- tandem mass spectrometry( UPLC- MS / MS) was established.... A method of rapidly detecting three kinds of microcystins( MCs) in environmental water samples by using disk SPE- ultra high performance liquid chromatography- tandem mass spectrometry( UPLC- MS / MS) was established. Firstly,environmental water samples were extracted by disk SPE column( C_(18)),and three kinds of MCs were separated by Waters BEH C_(18) chromatographic column with acetonitrile- 0. 2% formic acid solution as the mobile phase. After the gradient elution separation,the external standard method was used for quantitative and qualitative analysis under MRM of UPLC- MS / MS. The results showed that the three kinds of MCs in the range of 0. 05- 10 μg / L showed good linear relation,and the correlation coefficients were higher than 0. 999 4,while the method detection limit was 0. 04 ng / L. Under 0. 1,1,and 5 μg / L standard addition for the same environmental sample,the average recovery was 82. 8%- 108. 8%,and the relative standard deviation of determination results was2. 1%- 10. 1%( n = 6). This method is rapid,sensitive and accurate,so it can be effectively applied in the monitoring of MCs in environmental water samples. 展开更多
关键词 Disk SOLID-phase extraction COLUMN ultra performance liquid chromatography-tandem mass SPECTROMETRY Environmental water sample MICROCYSTINS Lake Chao China
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Determination of Quinolone Antibiotics in Water Using Solid Phase Extraction-High Performance Liquid Chromatography-Fluorescence Method
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作者 WANG Qiao-jun YI Ru-han MO Ce-hui 《Animal Husbandry and Feed Science》 CAS 2011年第2期45-48,共4页
[Objective] To develop a solid phase extraction-high performance liquid chromatography-fluorescence method for determination of quin- olone antibiotics in water. [ Metbod] The standard curves of four quinolones (norf... [Objective] To develop a solid phase extraction-high performance liquid chromatography-fluorescence method for determination of quin- olone antibiotics in water. [ Metbod] The standard curves of four quinolones (norfloxacin, ciprofloxacin, Iomefloxacin and enrofloxacin) were pre- pared. The detection limit in water and recovery were determined. The water samples collected from different areas, river and tap water were trea- ted using solid-phese extraction method and analyzed by high performance liquid chromatography. Then the concentration of quinolones antibiotics was determined by fluorescence method. [ Result] The detection limit of quinolone antibiotics in water was 0.083 -0.248 μg/L, and their recovery was 63.7% -134.1%. The four quinolone antibiotics at different levels were detected in various water samples, and the total concentration of quin- olone antibiotics was 0.045 -3.969 μg/L. The total concentration of quinolone antibiotics was higher in the water samples collected from rivers in Shenzhen area than in the sewage samples. The four quinolone antibiotics could be detected in all tap water samples. [ CoaduLsion ] The solid phase extraction-high performance liquid chromatography-fluorescence method is feasible and effective to detect quinolones in water. In addition, this method needs low cost and can meet requirements of daily monitorina and analysis. 展开更多
关键词 Solid-phase extraction High performance liquid chromatography WATER Quinolone antibiotics
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Lysophosphatidylcholine Biomarkers of Lung Cancer Detected by Ultra-performance Liquid Chromatography Coupled with Quadrupole Time-of-flight Mass Spectrometry
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作者 DONG Jun CAI Xiao-ming +4 位作者 ZOU Li-juan CHEN Cheng XUE Xing-ya ZHANG Xiu-li LIANG Xin-miao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期750-755,共6页
Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients a... Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients and 34 healthy volunteers were prepared with this approach. With ultra-performance liquid chromatography(UPLC) coupled with quadrupole time-of-flight mass spectrometry(Q-TOF MS) analysis, the samples were investigated in order to find potential disease biomarkers. After data acquisition, orthogonal signal correction partial least squares models were built to differentiate the healthy volunteers from lung cancer patients and to identify metabolites that showed significantly different expression between the two groups. Several metabolite ions were identified as potential biomarkers according to the variable importance in the project(VIP) value in both ion modes. Five lysophosphatidylcholines were further identified as specifically lysoPC 16:0, isomer of lysoPC 16:0, lysoPC 18:0, lysoPC 18:1 and lysoPC 18:2. These results suggest that UPLC coupled with Q-TOF MS is an effective technique for the analysis of plasma metabolites in metabonomic studies. 展开更多
关键词 METABONOMICS Sample preparation ultra-performance liquid chromatography coupled with quadrupoletime-of-flight mass spectrometry(UPLC/Q-TOF MS) Lung cancer Biomarker
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