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Analysis of Pesticide Raid^(█) in Feed of Wistar Rat by High-Pressure Liquid Chromatography (HPLC)
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作者 Albert C. Achudume 《American Journal of Analytical Chemistry》 2011年第8期32-36,共5页
The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 μg. Results show bioaccumulation factor of pestic... The distribution of pesticide by-product in tissues of wistar rats were analyzed using high pressure liquid chromatography. The limit of detection of the HPLC was 0.1 μg. Results show bioaccumulation factor of pesticide “Raid?” in lipid, up to three times that of the feed at the first concentration and gradually decreased as the concentration increased in the muscle > (0.7), brain > (0.5) and liver > (0.3) as indicated in the text. At higher concentration of 961 μg/g, bioaccumulation factor decreased in the lipid to 1.2 and 0.6 in the muscle, 0.03 in the brain and 0.08 in the liver respectively. High Pressure Liquid Chromatography (HPLC) analysis of raid extract suggests the presence of micprothrin and palethrin. The implications are numerous, but simply put that accidental ingestion of chlorinated hydrocarbon as in “Raid?” may involve convulsions, collapse and coma after only brief excitation and ataxia at the onset. 展开更多
关键词 High Pressure liquid chromatography PESTICIDE Raid^(█) Chlorinated Hydrocarbon BIOACCUMULATION
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Efficient and selective extraction of uranium from seawater based on a novel pulsed liquid chromatography radionuclide separation method 被引量:2
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作者 Jian‑Hua Ye Tao Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期13-27,共15页
The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from seawater.In this study,a new chromatographic separation met... The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from seawater.In this study,a new chromatographic separation method was proposed,and a pulsed nuclide automated separation device was developed,alongside a new chromatographic column.The length of this chromatographic column was 10 m,with an internal warp of 3 mm and a packing size of 1 mm,while the total separation units of the column reached 12,250.The most favorable conditions for the separation of nuclides were then obtained through optimizing the separation conditions of the device:Sample pH in the column=2,sample injection flow rate=5.698 mL/min,chromatographic column heating temperature=60℃.Separation experiments were also carried out for uranium,europium,and sodium ions in mixed solutions;uranium and sodium ions in water samples from the Ganjiang River;and uranium,sodium,and magnesium ions from seawater samples.The separation factors between the different nuclei were then calculated based on the experimental data,and a formula for the separation level was derived.The experimental results showed that the separation factor in the mixed solution of uranium and europium(1:1)was 1.088,while achieving the initial separation of uranium and europium theoretically required a 47-stage separation.Considering the separation factor of 1.50for the uranium and sodium ions in water samples from the Ganjiang River,achieving the initial separation of uranium and sodium ions would have theoretically required at least a 21-stage separation.Furthermore,for the seawater sample separation experiments,the separation factor of uranium and sodium ions was 1.2885;therefore,more than 28 stages of sample separation would be required to achieve uranium extraction from seawater.The novel pulsed liquid chromatography method proposed in this study was innovative in terms of uranium separation and enrichment,while expanding the possibilities of extracting uranium from seawater through chromatography. 展开更多
关键词 Pulsed liquid chromatography Nuclide separation Seawater uranium extraction Uranium enrichment
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Determination of Voriconazole in Human Plasma by Liquid Chromatography Tandem Mass Spectrometry: Application in Therapeutic Drug Monitoring
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作者 Waleed Alhussaini Ezzeldeen Ghanem +4 位作者 Magd Alsahly Amani Kurdi Eman Alharbi Imadul Islam Majed Aljeraisy 《American Journal of Analytical Chemistry》 2023年第9期378-389,共12页
A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with flucona... A sensitive, accurate and robust Liquid Chromatography Tandem Mass Spectrometry method has been developed and validated to measure voriconazole trough levels in human plasma. The plasma samples were mixed with fluconazole as an Internal Standard and directed to protein precipitation and drug extraction. An aliquot of 1 μl was injected into the chromatographic system and separated by the Acquity BEH C18 column at a flow rate of 0.30 ml/min in a gradient mobile phase consisting of acetonitrile, Ultrapure water (UPW), methanol and formic acid. Voriconazole was detected by a Triple Quadrupole Detector (TQD) operating on Multiple Reaction Monitoring (MRM) and a positive ion mode Electrospray ionization (ESI) Q1 mass: 350.1 m/z, Q3 mass: 281.1 m/z. Method linearity of the calibration curve (0.10 - 8.00 μg/ml) indicated a correlation coefficient r ≥ 0.99. The intra and inter-assay accuracy was within 85% - 115% and the intra and inter-assay precision was ≤5.76%. Voriconazole recovery percentage was between 97.69 - 119.62%. The method was successively applied in routine voriconazole TDM. 展开更多
关键词 VORICONAZOLE Human Plasma liquid chromatography Tandem Mass Spectrometry Therapeutic Drug Monitoring
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A High-Performance Liquid Chromatography Method for the Simultaneous Determination of Five Index Components in Danhong Injection
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作者 Yun An Tian Tian +2 位作者 Qinglin Wang Xingchu Gong Chenchen Zhang 《American Journal of Analytical Chemistry》 2023年第11期481-492,共12页
The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, a... The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. The chromatographic method employed was as follows: the column was a Welch Ultimate XB-C18 column (250 mm × 4.6 mm, 10 μm), the mobile phase was a gradient elution of 0.4% formic acid aqueous solution (A) and acetonitrile (B), the detection wavelengths were 280 nm for sodium danshensu, protocatechuic aldehyde, and salvianolic acid B and 326 nm for 4-coumaric acid and rosmarinic acid, the sample volume was 10 μL, the flow rate was 1.0 mL/min, and the column temperature was 35°C. This method can realize the separation and determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid within 50 minutes. The linear relationships of the five peak areas and their concentrations are good (R<sup>2</sup>> 0.9997). The precision RSD values are all less than 1.0%. The reproducibility RSD values are all less than 1.3%. The stability RSD values are all less than 2.2%. The recovery values ranged from 92.4% to 99.4%. This method is simple, accurate, and reproducible. It can be used for the determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. 展开更多
关键词 Danhong Injection High Performance liquid chromatography Phenolic Acid FLAVONOIDS
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Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I.Development and Assesment of Chromatographic Conditions 被引量:4
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1998年第2期97-104,共8页
Plantrootsexudeavarietyoforganiccompoundstotherhizosphere.Theamountofrootexudates,expresedasafractionoftheto... Plantrootsexudeavarietyoforganiccompoundstotherhizosphere.Theamountofrootexudates,expresedasafractionofthetotaldrymaterproduc... 展开更多
关键词 高效液相色谱法 有机酸 大豆 根围 根部分泌液 测定
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Studies on Chromatography Fingerprint of Hongqi by High-performance Liquid Chromatography 被引量:2
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作者 ShiLanFENG FangDiHU +2 位作者 JianXiongZHAO JingWenXU LiRenCHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第11期1335-1338,共4页
Chromatography fingerprint (CFP) of 10 samples of hongqi were studied. 23 common peaks were analyzed, their average similarity was 97.29%. CFP were positioned with main index composition such as formononetin, calyco... Chromatography fingerprint (CFP) of 10 samples of hongqi were studied. 23 common peaks were analyzed, their average similarity was 97.29%. CFP were positioned with main index composition such as formononetin, calycosin and then the contents of index composition were determined. The character and exclusive of CFP of 10 samples of hongqi were clear. CFP and content determination of index composition of hongqi could be used to evaluate the quality of hongqi comprehensively. 展开更多
关键词 Hongqi chromatography fingerprint high-performance liquid chromatography.
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Simultaneous determination of 15 pesticide residues in Chinese cabbage and cucumber by liquid chromatography-tandem mass spectrometry utilizing online turbulent flow chromatography 被引量:5
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作者 Sufang Fan Junmei Ma +5 位作者 Meirong Cao Juan Wang Leilei Zhang Yan Zhang Qiang Li Jia Chen 《Food Science and Human Wellness》 SCIE 2021年第1期78-86,共9页
In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purificatio... In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples. 展开更多
关键词 Pesticide residues Online turbulent flow chromatography liquid chromatography-tandem mass SPECTROMETRY
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Analysis of ganciclovir and its related substances using high performance liquid chromatography and liquid chromatography-mass spectrometry methods 被引量:1
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作者 Cheng-Ping Li1,2,Mao Mao1,Lan-Jun Zheng1,Wei-Guang Shan11.College of Pharmaceutical Sciences,Zhejiang University of Technology,Hangzhou 310032 2.College of Biology and Environment Engineering,Zhejiang Shuren University,Hangzhou 310015,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2010年第4期218-222,共5页
Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 co... Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 column(4.6 mm×250 mm,5 μm)was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer(pH 6.0)-methanol(92∶8)at a flow rate of 1.0 mL/min,and UV detector set at 254 nm was used for monitoring the eluents.Results The method was simple,rapid,selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL.It has been validated with respect to accuracy,precision,linearity,and limits of detection and quantification.The linearity range was 10.2-153.0 μg/mL with r=0.9998.The percentage recoveries ranged from 96.7% to 101.6%,and RSD was 1.24%-1.96%(n=5).Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir.For identification of related substances,LC/MS was used.The mainly related substances of ganciclovir active pharmaceutical ingredients(API)were determined as guanine,(1,3-dioxolan-4-yl)methyl acetate,and diacetyl guanine. 展开更多
关键词 GANCICLOVIR related substances high performance liquid chromatography high performance liquid chromatography/mass spectrometry
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Comparison of liquid-liquid extraction-thin layer chromatography with solid-phase extraction-high-performance thin layer chromatography in detection of urinary morphine 被引量:1
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作者 Ali Ahadi Alireza Partoazar +1 位作者 Mohammad Hassan Abedi Khorasgani Seyed Vahid Shetab Boushehri 《The Journal of Biomedical Research》 CAS 2011年第5期362-367,共6页
Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tr... Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, 'were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories. 展开更多
关键词 morphine detection liquid-liquid extraction thin-layer chromatography solid-phase extraction highperformance thin layer chromatography
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Screening and Identifying of Nephrotoxic Compounds in Lithospermum erythrorhizon Using Live-cell Fluorescence Imaging and Liquid Chromatography Coupled with Tandem Mass Spectrometry
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作者 ZHAO Xiao-ping JIN Ye-cheng +2 位作者 ZENG Xing ZHANG Bo-li ZHANG Yu-feng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期562-565,共4页
In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized ... In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 "C09 and C12 "C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after they were treated with these fractions.These potential nephrotoxic fractions were further analyzed by multistage and high resolution mass spectrometry.The main compounds in these fractions were tentatively identified to be acetylshikonin,isobutyrylshikonin,β,β'-dimethyla-cryloylshikonin,and isovalerylshikonin,which may bring nephrotoxicity. 展开更多
关键词 Traditional Chinese medicine Nephrotoxic compound liquid chromatography/ion-trap mass spectrome-try(LC/IT-MS) liquid chromatography/time-of-flight mass spectrometry(LC/TOF-MS) Lithospermum erythrorhizon
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Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography 被引量:10
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作者 Zhi Mei Liu Xiao Huan Zang Wei Hua Liu Chun Wang Zhi Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期213-216,共4页
A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) ... A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) coupled with high performance liquid chromatography-diode array detector (HPLC-DAD). Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients (r^2) varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection (LODs) (S/N = 3) were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples. 展开更多
关键词 Carbamate pesticides High performance liquid chromatography Diode array detection Dispersive liquid-liquid microextraction Water samples
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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:9
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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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Development of the fingerprints for the quality evaluation of Viscum coloratum by high performance liquid chromatography 被引量:6
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作者 Yun-Li Zhao Rong-Hua Fan +3 位作者 Hong-Xia Yuan Miao Yu Kai-Shun Bi Zhi-Guo Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第2期113-118,共6页
A high-performance liquid chromatography coupled ultraviolet (HPLC-UV) method was developed for a chemical fingerprint analysis of Viscum coloratura. Eighteen peaks were selected as the common peaks and Homoeriodict... A high-performance liquid chromatography coupled ultraviolet (HPLC-UV) method was developed for a chemical fingerprint analysis of Viscum coloratura. Eighteen peaks were selected as the common peaks and Homoeriodictyol-7-O-β-D-apiosiyl-(1→2)-β-D-glucoside was used as a reference. The relative areas of common peaks were used for hierarchical clustering analysis and similarity calculation. Thirty-seven samples collected from different sources were classified into five groups. The similarities of 21 batches Viscum coloratura samples were beyond 0.90. The results obtained suggest that the chromatographic fingerprint can efficiently identify Viscum coloratum. Additionally, the fingerprints can then be used to evaluate the correlation between Viscum coloratura and hosts. 展开更多
关键词 Viscum coloratum QUALITY high-performance liquid chromatography FINGERPRINT
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Screening potential mitochondria-targeting compounds from traditional Chinese medicines using a mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry method 被引量:5
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作者 Xing-Xin Yang Yu-Zhen Zhou +5 位作者 Feng Xu Jie Yu Gegentana Ming-Ying Shang Xuan Wang Shao-Qing Cai 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2018年第4期240-249,共10页
Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based ce... Mitochondria regulate numerous crucial cell processes, including energy production, apoptotic cell death, oxidative stress, calcium homeostasis and lipid metabolism. Here, we applied an efficient mitochondria-based centrifugal ultrafiltration/liquid chromatography/mass spectrometry(LC/MS) method,also known as screening method for mitochondria-targeted bioactive constituents(SM-MBC). This method allowed searching natural mitochondria-targeting compounds from traditional Chinese medicines(TCMs), including Puerariae Radix(PR) and Chuanxiong Radix(CR). A total of 23 active compounds were successfully discovered from the two TCMs extracts. Among these 23 hit compounds, 17 were identified by LC/MS, 12 of which were novel mitochondria-targeting compounds. Among these, 6 active compounds were analyzed in vitro for pharmacological tests and found able to affect mitochondrial functions. We also investigated the effects of the hit compounds on Hep G2 cell proliferation and on loss of cardiomyocyte viability induced by hypoxia/reoxygenation injury. The results obtained are useful for in-depth understanding of mechanisms underlying TCMs therapeutic effects at mitochondria level and for developing novel potential drugs using TCMs as lead compounds. Finally, we showed that SM-MBC was an efficient protocol for the rapid screening of mitochondria-targeting constituents from complex samples such as PR and CR extracts. 展开更多
关键词 MITOCHONDRIA Bioactive constituents Traditional Chinese medicines Centrifugal ultrafiltration liquid chromatography/mass spectrometry
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Determination of gouty arthritis' biomarkers in human urine using reversed-phase high-performance liquid chromatography 被引量:4
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作者 Lei-Wen Xiang Jing Li +1 位作者 Jin-Ming Lin Hai-Fang Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第2期153-158,共6页
Creatinine, uric acid, hypoxanthine and xanthine are important diagnostic biomarkers in human urine for gouty arthritis or renal disease diacrisis. A simple method for simultaneous determination of these biomarkers in... Creatinine, uric acid, hypoxanthine and xanthine are important diagnostic biomarkers in human urine for gouty arthritis or renal disease diacrisis. A simple method for simultaneous determination of these biomarkers in urine based on reversed-phase high-performance liquid chromatography (RP-HPLC) with ultraviolet (UV) detector was proposed. After pretreatment by dilution, centrifugation and filtration, the biomarkers in urine samples were separated by ODS-BP column by elution with methanol/50 mM NaH2PO4 buffer solution at pH 5.26 (5:95). Good linearity between peak areas and concentrations of standards was obtained for the biomarkers with correlation coefficients in the range of 0.9957-0.9993. The proposed analytical method has satisfactory repeatability (the recovery of data in a range of creatinine, uric acid, hypoxanthine and xanthine was 93.49-97.90%, 95.38-96.45%, 112.46-115.78%and 90.82-97.13%with standard deviation of o5%, respectively) and the limits of detection (LODs, S/N Z 3) for creatinine, uric acid, hypoxanthine, and xanthine were 0.010, 0.025, 0.050 and 0.025 mg/L, respectively. The established method was proved to be simple, accurate, sensitive and reliable for the quantitation of gouty arthritis' biomarkers in human urine samples. The ratio of creatinine to uric acid was found to be a possible factor for assessment of gouty arthritis. 展开更多
关键词 Gouty arthritis CREATININE Uric acid HYPOXANTHINE XANTHINE High-performance liquid chromatography
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Dispersive Liquid-liquid Microextraction Combined with High-performance Liquid Chromatography for the Determination of Clozapine and Chlorpromazine in Urine 被引量:3
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作者 陈静 熊朝梅 +1 位作者 阮金兰 苏邹 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2011年第2期277-284,共8页
A simple method has been proposed for the determination of clozapine (CLZ) and chlorpromazine (CPZ) in human urine by dispersive liquid-liquid microextraction (DLLME) in combination with high-performance liquid ... A simple method has been proposed for the determination of clozapine (CLZ) and chlorpromazine (CPZ) in human urine by dispersive liquid-liquid microextraction (DLLME) in combination with high-performance liquid chromatography-ultraviolet detector (HPLC-UV). All important variables influencing the extraction efficiency, such as pH, types of the extraction solvent and the disperser solvent and their volume, ionic strength and centrifugation time were investigated and optimized. Under the optimal conditions, the limit of detection (LODs) and quantification (LOQs) of the method were 13 and 39 ng/mL for CLZ, and 2 and 6 ng/mL for CPZ, respectively. The relative standard deviations (RSDs) of the targets were less than 5.1% (C=0.100 μg/mL, n=9). Good linear behaviors over the tested concentration ranges were obtained with the values of R20.999 for the targets. The absolute extraction efficiencies of CLZ and CPZ from the spiked blank urine samples were 98.3% and 97.8%, respectively. The applicability of the technique was validated by analyzing urine samples and the mean recoveries for spiked urine samples ranged from 93.3% to 105.0%. The method was successfully applied for the determination of CLZ and CPZ in real human urine. 展开更多
关键词 dispersive liquid-liquid microextraction CLOZAPINE CHLORPROMAZINE high-performance liquid chromatography human urine
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Offline two-dimensional liquid chromatography coupled with ion mobility-quadrupole time-of-flight mass spectrometry enabling fourdimensional separation and characterization of the multicomponents from white ginseng and red ginseng 被引量:9
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作者 Tiantian Zuo Chunxia Zhang +7 位作者 Weiwei Li Hongda Wang Ying Hu Wenzhi Yang Li Jia Xiaoyan Wang Xiumei Gao Dean Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期597-609,共13页
Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensi... Inherent complexity of plant metabolites necessitates the use of multi-dimensional information to accomplish comprehensive profiling and confirmative identification.A dimension-enhanced strategy,by offline two-dimensional liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(2 D-LC/IM-QTOF-MS)enabling four-dimensional separations(2 D-LC,IM,and MS),is proposed.In combination with in-house database-driven automated peak annotation,this strategy was utilized to characterize ginsenosides simultaneously from white ginseng(WG)and red ginseng(RG).An offline 2 DLC system configuring an Xbridge Amide column and an HSS T3 column showed orthogonality 0.76 in the resolution of ginsenosides.Ginsenoside analysis was performed by data-independent high-definition MSE(HDMSE)in the negative ESI mode on a Vion?IMS-QTOF hybrid high-resolution mass spectrometer,which could better resolve ginsenosides than MSEand directly give the CCS information.An in-house ginsenoside database recording 504 known ginsenosides and 58 reference compounds,was established to assist the identification of ginsenosides.Streamlined workflows,by applying UNIFI?to automatedly annotate the HDMSEdata,were proposed.We could separate and characterize 323 ginsenosides(including 286 from WG and 306 from RG),and 125 thereof may have not been isolated from the Panax genus.The established 2 D-LC/IM-QTOF-HDMSEapproach could also act as a magnifier to probe differentiated components between WG and RG.Compared with conventional approaches,this dimensionenhanced strategy could better resolve coeluting herbal components and more efficiently,more reliably identify the multicomponents,which,we believe,offers more possibilities for the systematic exposure and confirmative identification of plant metabolites. 展开更多
关键词 Dimension-enhanced strategy Multicomponent characterization GINSENOSIDE Offline two-dimensional liquid chromatography Ion mobility-quadrupole time-of-flight mass spectrometry In-house database
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Determination of the Flavonoids from Ginkgo Biloba Extract by High Performance Liquid Chromatography 被引量:3
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作者 Li ZHANG Zhi Min XIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期968-970,共3页
HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns, symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile ph... HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns, symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile phase, which can eliminate the time for cleaning the chromatographic system and simplify the analystic method for GBE. Experimental conditions: column: Hypersil BDS C18,5mm×4×250 mm; column temperature: 35C; mobile phase: 46% methanol-54% water; flow rate: 0.7 mL/min; detection wavelength: 360nm. 展开更多
关键词 ginkgo biloba extract flavone glycoside high performance liquid chromatography
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Novel guanidinium-based ionic liquids as stationary phases for capillary gas chromatography 被引量:3
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作者 Li Zhen Qiao Kai Lu +1 位作者 Mei Ling Qi Ruo Nong Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第9期1133-1136,共4页
The present study describes guanidinium-based ionic liquids(GBILs) as stationary phases for capillary gas chromatography (CGC) and to the best of our knowledge,no related reports are available up to now.In this st... The present study describes guanidinium-based ionic liquids(GBILs) as stationary phases for capillary gas chromatography (CGC) and to the best of our knowledge,no related reports are available up to now.In this study,a hexaalkylguanidinium ionic liquid(DOTMG-NTf;) was synthesized and coated statically onto capillary columns.Selectivity of the stationary phase was evaluated by separating Grob test mixture,test mixture,alcohols mixture,and fatty acid methyl esters mixture,and thermal stability was investigated as well.The present study demonstrates that GBILs as CGC stationary phases exhibit satisfactory selectivity and thermal stability and have a great potential as new candidates for CGC stationary phases. 展开更多
关键词 Guanidinium-based ionic liquids Capillary gas chromatography Stationary phase
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A novel ionic liquids grafted polysiloxane for capillary gas chromatography 被引量:2
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作者 Qing Quan Wei Mei Ling Qi Ruo Nong Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1111-1114,共4页
A new ionic liquids grafted polysiloxane used as stationary phase for capillary gas chromatography (CGC) is described. The stationary phase of 1-vinyl-3-hexylimidazolium hexafluorophosphate anchored to polysiloxane ... A new ionic liquids grafted polysiloxane used as stationary phase for capillary gas chromatography (CGC) is described. The stationary phase of 1-vinyl-3-hexylimidazolium hexafluorophosphate anchored to polysiloxane (PMHS-[VHIm][PF6]) was synthe- sized, characterized and coated onto capillary columns by static coating. The results show that the present stationary phase exhibits a very good chromatographic resolution and selectivity for Grob test mixture and alcohols with baseline resolution and symmetry peaks. The present work suggests that novel stationary phase has a great potential for further development and application. 2009 Mei Ling Qi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Ionic liquids POLYSILOXANE Stationary phase Gas chromatography
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