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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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Ultra-performance liquid chromatography electrospray ionization-tandem mass spectrometry method for the simultaneous determination of itraconazole and hydroxy itraconazole in human plasma 被引量:1
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作者 Ashish Dwivedi Bhupinder Singh +2 位作者 Sandeep Sharma R.S.Lokhandae Naveen Dubey 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第5期316-324,共9页
A highly sensitive, selective, and precise ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for simultaneous quantification of itraconazole and hydroxy itraconazole i... A highly sensitive, selective, and precise ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for simultaneous quantification of itraconazole and hydroxy itraconazole in human plasma by a single liquid-liquid extraction step. The precursor to product ion transitions of m/z 705.3/392.3, m/z 721.2/408.3 and m/z 708.2/435.4 were used to detect and quantify itraconazole, hydroxy itraconazole and itraconazole-d3 respectively. The lower limit of quantitation was found to be 0.500 ng/mL for itraconazole and 1.00 ng/mL for hydroxy itraconazole. The mean recoveries for itraconazole and hydroxy itraconazole were found to be 100.045% and 100.021%, respectively. This developed method with a chromatographic run time of 2.0 min was successfully applied to a bioequivalence study of 100 mg itraconazole capsule. 展开更多
关键词 Itraconazole Hydroxy itraconazole ultra-performance liquidchromatography Human plasma Simultaneous analysis
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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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Determination of Sodium Pentachlorophenoxide Residues in Animal-derived Foods by Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS)
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作者 Chengmei WANG Chunxia CHENG +2 位作者 Guixia YANG Susu ZHANG Xuan QIAN 《Agricultural Biotechnology》 CAS 2022年第2期99-101,105,共4页
[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The ... [Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food. 展开更多
关键词 Sodium pentachlorophenoxide Ultra-high performance liquid chromatography-tandem mass spectrometry Animal-derived food Trace analysis
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Detecting N-nitrosamines in water treatment plants and distribution systems in China using ultra-performance liquid chromatography-tandem mass spectrometry 被引量:11
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作者 Chengkun WANG Xiaojian ZHANG +1 位作者 Jun WANG Chao CHEN 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第6期770-777,共8页
N-nitrosodimethylamine (NDMA) and several other N-nitrosamines have been detected as disinfection by-products in drinking waters in many countries around the world. An ultra-performance liquid chromatography- tandem... N-nitrosodimethylamine (NDMA) and several other N-nitrosamines have been detected as disinfection by-products in drinking waters in many countries around the world. An ultra-performance liquid chromatography- tandem mass spectrometry method with solid phase extraction sample preparation was developed to study the occurrence of N-nitrosamines in several water treatment plants and distribution systems in China. Isotope labeled N-nitrosodi-n-propylamine-dl4 (NDPA-dl4) was selected as the internal standard for quantification. The solid phase extraction procedures including pH, enrichment process and MS/MS parameters including capillary voltage, cone gas flow, cone voltage, collision energy were optimized to give average recoveries of 26% to 112% for nine N- nitrosamine species. The instrument detection limits were estimated to range from 0.5 to 5μg.L-1 for the nine N- nitrosamine species. NDMA and several other N-nitrosa- mines were found at fairly high concentrations in several water treatment plants and distribution systems. NDMA was found in all locations, and the highest concentrations in cities B, G, T, and W were 3.0, 35.7, 21.3, and 19.7 ng. L 1, respectively. A wide range of N-nitrosamines concentrations and species were observed in different locations. Higher concentrations of N-nitrosamines were detected in distribution systems that were further away from the treatment plants, suggesting that the contact time between the residual disinfectant and natural organic matter may play an important role in the formation of these compounds. 展开更多
关键词 N-NITROSAMINES water treatment plant distri-bution system ultra-performance liquid chromatography-tandem mass spectrometry
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Study of Differential Serum Metabolites in Patients with Adenomatous Polyps of Colon and Yang-Deficiency Constitution Based on Ultra-Performance Liquid Chromatography-Mass Spectrometry 被引量:2
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作者 DU Wen-zhang ZHANG Ai-hua +3 位作者 REN Jun-ling LYU Kun TUO Lu-yao XU Wei 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2022年第5期403-409,共7页
Objective:To study the differences between the serum metabolites in patients with adenomatous polyps of the colon and yang-deficiency constitution and those without colon polyps and with balanced constitution,and look... Objective:To study the differences between the serum metabolites in patients with adenomatous polyps of the colon and yang-deficiency constitution and those without colon polyps and with balanced constitution,and look for biomarkers that can be used to distinguish between the two groups.Methods:General patient information was gathered,and Chinese medicine constitutions were collected in 940 patients who underwent electronic colonoscopy.A total of 119 patients with adenomatous polyps of the colon and yang-deficiency constitution were included in the experimental group,and 150 patients without colon polyps and with balanced constitution were included in the control group.Metabolomics analysis was performed on the fasting venous blood obtained from each patient in both groups.Principal component analysis and orthogonal partial least squares discriminant analysis were performed on the detection results,potential biomarkers were screened,metabolic pathway changes were determined,and the metabolic processes involved were discussed.Results:A total of 59 differential biomarkers between the experimental group and the control group were identified.The differential metabolites were found mainly in the glycerophospholipid metabolism pathway,and the bile acid 3-oxo-4,6-choladienoic acid was the biomarker that distinguished the experimental group from the control group.Conclusions:With the help of metabolomics analysis,the differential metabolites in patients with adenomatous polyps of the colon and yang-deficiency constitution and those in patients without colon polyps and with balanced constitution could be identified.The biomarker 3-oxo-4,6-choladienoic acid may have potential diagnostic value in patients with adenomatous polyp of the colon and yang-deficiency constitution.(Trial Registration No.NCT02986308) 展开更多
关键词 ultra-performance liquid chromatography-mass spectrometry adenomatous polyps yang-deficiency constitution Chinese medicine metabolomics biomarkers
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Pharmacokinetic Comparison of Four Major Bio-Active Components of Naoxintong Capsule in Normal and Acute Blood Stasis Rats Using Ultra-Performance Liquid Chromatography Coupled with Triple-Quadrupole Mass Spectrometry 被引量:1
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作者 Wei-Xia Li Shu-Qi Zhang +5 位作者 Man-Man Li Hui Zhang Xiao-Yan Wang Lu Niu Jin-Fa Tang Xue-Lin Li 《World Journal of Traditional Chinese Medicine》 2022年第1期92-99,共8页
Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline ... Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline hydrochloride twice;during the two subcutaneous injections, the rats were placed in ice water for 4 min to reproduce the model rat of acute blood stasis. The normal and acute blood stasis rats were administrated a 5.04 g/kg dose of NXTC suspension. Then, blood samples were collected from the posterior retinal venous plexus at different time points. Plasma concentrations of four major bio-active components including caffeic acid, ferulic acid, formononetin, and tanshinone IIA in NXTC were measured using ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry. Phoenix Win Nonlin v6.2 software was used to calculate the pharmacokinetic parameters. Results: Compared with the normal rats, the acute blood stasis rats showed a significant decrease in C_(max) of ferulic acid and formononetin, AUC_(all) of caffeic acid and ferulic acid, and AUC_(INF_obs) of ferulic acid. Conversely, an increase in the Vz_F_obs and MRT_(last) of ferulic acid and caffeic acid was observed. These findings demonstrate that the absorption of the four NXTC components was weakened in the acute blood stasis rats and that the elimination time was prolonged. Conclusions: The significant difference in some parameters of the four NXTC components between the normal and acute blood stasis rats might be caused by an increase in blood viscosity and the subsequent slowing down of blood flow in the acute blood stasis rats. The pharmacokinetic study conducted in pathological state can provide important information and scientific basis for further rational clinical application of NXTC. 展开更多
关键词 Acute blood stasis rat model Naoxintong capsules PHARMACOKINETICS ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry
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Rapid Differentiation of Aconiti Kusnezoffii Radix from Different Geographic Origins Using Ultra-Performance Liquid Chromatography Coupled with Time-of-Flight Mass Spectrometry 被引量:1
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作者 En-Yu Lu Zi-Feng Pi +4 位作者 Zhong Zheng Shu Liu Feng-Rui Song Na Li Zhi-Qiang Liu 《World Journal of Traditional Chinese Medicine》 2021年第1期71-77,共7页
Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographi... Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographic origins of AKRs and to realize the rapid evaluation of their quality.Methods:An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry(UPLC-Q-TOF MS)method was utilized to acquire the constituents'information of AKRs from different geographic origins.MSE data and Progenesis QI software were employed to identify the chemical constitutes.Principal component analysis(PCA)was applied to comparing MS data to find the chemical markers of AKRs from different geographic origins.Results:Twenty-three components were detected and 17 out of them were identified,including diester-diterpenoid alkaloids,monoester-diterpenoid alkaloids,and amine-diterpenoid alkaloids.Three pairs of isomers were detected and two of them were distinguished by the retention time of standard samples.Thirteen chemical markers were screened out through PCA and orthogonal partial least square discriminant analysis.Through detecting Napelline or isomer of Napelline(m/z 360.2530)and Aconifine(m/z 662.3170),AKRs from inner Mongolia autonomous could be screened.According to the existence of benzoylaconine(m/z 604.3108)and Indaconitine(m/z 630.3159),it could be confirmed that the AKRs are from Xinjiang Uygur autonomous.AKRs that cannot detect compounds above-mentioned could be from Liaoning or Shanxi Province.Conclusions:The chemical profile could be used not only to distinguish the AKRs from different geographic origins but also to identify the true and false of AKRs.This study lays a foundation for the study of efficacy and toxic of AKRs. 展开更多
关键词 Aconiti Kusnezoffii Radix chemical markers rapid differentiation ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry
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Simultaneous Determination of Six Compounds in Rat Plasma by Ultra-Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan-Shu Yu-Fang 被引量:1
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作者 Hai Jiang A-Jiao Houa +10 位作者 Yan-Yan Zhang Wen-Jing Man Liu Yang Yong-Hai Meng Xin-Yue Guo Song Wang Jia-Xu Zhang Bing-You Yang Qiu-Hong Wang Kelvin Chan Hai-Xue Kuang 《World Journal of Traditional Chinese Medicine》 2019年第4期250-259,共10页
A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,s... A rapid and high selective ultra-performance liquid chromatography(UPLC)with tandem mass spectrometry method for simultaneous determination of six compounds including albiflorin,paeoniflorin,picroside I,picroside II,saikosaponin A,and saikosaponin D in rat plasma was developed and validated using butyl p-hydroxybenzoate as an internal standard.One-step direct protein precipitation with acetonitrile was used to extract the compounds from the rat plasma samples.Chromatographic separation was achieved using an ACQUITY UPLC BEH C18 column(100 mm×2.1 mm,1.7μm)at a flow rate of 0.4 m L/min,using gradient mode containing 0.1%formic acid in water and acetonitrile were used as the Mobile phase A and B.Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify and quantify active components.Calibration curves showed good linearity(R^2>0.9908)over a wide concentration range for all compounds.The intra-and interday precision(relative standard deviation)ranged 2.4%–7.0%and 2.6%–8.0%,respectively.The accuracy(relative error)was from-13.0%to 13.2%at all quality control levels.The recovery ranged from 81.1%to 92.5%.The validated method was successfully applied to pharmacokinetic study in rats after oral administration of Qing Gan-Shu Yu-Fang.The results show that one can draw a conclusion that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo. 展开更多
关键词 PHARMACOKINETICS traditional Chinese medicine prescriptions ultra-performance liquid chromatography with tandem mass spectrometry
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Analysis of Serum Metabolic Profile by Ultra-performance Liquid Chromatography-mass Spectrometry for Biomarkers Discovery: Application in a Pilot Study to Discriminate Patients with Tuberculosis 被引量:6
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作者 Shuang Feng Yan-Qing Du +3 位作者 Li Zhang LeiZhang Ran-Ran Feng Shu-Ye Liu 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第2期159-168,共10页
Background:Tuberculosis (TB) is a chronic wasting inflammatory disease characterized by multisystem involvement,which can cause metabolic derangements in afflicted patients.Metabolic signatures have been exploited ... Background:Tuberculosis (TB) is a chronic wasting inflammatory disease characterized by multisystem involvement,which can cause metabolic derangements in afflicted patients.Metabolic signatures have been exploited in the study of several diseases.However,the serum that is successfully used in TB diagnosis on the basis of metabolic profiling is not by much.Methods:Orthogonal partial least-squares discriminant analysis was capable of distinguishing TB patients from both healthy subjects and patients with conditions other than TB.Therefore,TB-specific metabolic profiling was established.Clusters of potential biomarkers for differentiating TB active from non-TB diseases were identified using Mann-Whitney U-test.Multiple logistic regression analysis of metabolites was calculated to determine the suitable biomarker group that allows the efficient differentiation of patients with TB active from the control subjects.Results:From among 271 participants,12 metabolites were found to contribute to the distinction between the TB active group and the control groups.These metabolites were mainly involved in the metabolic pathways of the following three biomolecules:Fatty acids,amino acids,and lipids.The receiver operating characteristic curves of3D,7D,and 11D-phytanic acid,behenic acid,and threoninyl-γ-glutamate exhibited excellent efficiency with area under the curve (AUC) values of 0.904 (95% confidence interval [CI]:0.863-0.944),0.93 (95% CI:0.893-0.966),and 0.964 (95% CI:0.941-0.988),respectively.The largest and smallest resulting AUCs were 0.964 and 0.720,indicating that these biomarkers may be involved in the disease mechanisms.The combination of lysophosphatidylcholine (18∶0),behenic acid,threoninyl-γ-glutamate,and presqualene diphosphate was used to represent the most suitable biomarker group for the differentiation of patients with TB active from the control subjects,with an AUC value of 0.991.Conclusion:The metabolic analysis results identified new serum biomarkers that can distinguish TB from non-TB diseases.The metabolomics-based analysis provides specific insights into the biology of TB and may offer new avenues for TB diagnosis. 展开更多
关键词 METABOLITES Orthogonal Partial Least-squares Discriminant Analysis SERUM TUBERCULOSIS ultra-performance liquidChromatography-mass Spectrometry
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Ultra-performance Liquid Chromatography-Quadrupole/Time-of-Flight Mass Spectrometry Based Bile and Urine Metabonomics Study on the Ameliorative Effects of Curcuma wenyujin Rhizoma on Acute Blood Stasis in Rats
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作者 Min Hao Meng-Ting Zhao +6 位作者 Huang-Jin Tong De Ji Lin Li Lian-Lin Su Wei Gu Chun-Qin Mao Tu-Lin Lu 《World Journal of Traditional Chinese Medicine》 2022年第1期141-152,共12页
Background: Curcuma wenyujin rhizome(CWR) is a commonly used Chinese herbal medicine for treating blood stasis in China for 1000 of years. However, the underlying mechanism of CWR remains unclear. Aims and Objectives:... Background: Curcuma wenyujin rhizome(CWR) is a commonly used Chinese herbal medicine for treating blood stasis in China for 1000 of years. However, the underlying mechanism of CWR remains unclear. Aims and Objectives: The purpose of this study is to clarify the bioactive mechanism of CWR in treating blood stasis. Materials and Methods: In this study, pharmacological indexes, including hemorheology and four blood coagulation indexes were tested. Bile and urine metabolomics were engaged by UPLC-Q/TOF-MS. Multivariate statistical analysis were used to screen out differential endogenous metabolites. Results: The results indicated that CWR significantly ameliorated the hemorheology and coagulation functions of acute blood stasis(ABS) model rats. Moreover, 27 endogenous metabolites between the CWR group and the ABS group were screened, and the levels were all improved to certain degrees by CWR preadministration. Metabonomics results indicated that ABS was mainly related to linoleic acid metabolism, arachidonic acid metabolism, glycerophospholipid metabolism, sphingolipid metabolism, pentose and glucuronate intercereasonversions, steroid hormone biosynthesis, and primary bile acid biosynthesis. Conclusion: In a word, the metabolomics method is consistent with the holistic view of traditional Chinese medicine(TCM) that can be a powerful means to illustrate the biological activity mechanism of CWR in treating blood stasis and to offer research demonstration for further study on the effector mechanism of TCM. 展开更多
关键词 BILE Curcuma wenyujin rhizome metabolomics ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry URINE
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Commonalities and characteristics of aqueous extracts from three Uighur medicines were analyzed by using three-stage infrared spectroscopy combined with ultra-performance liquid chromatography-time of flight-mass spectra 被引量:1
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作者 Qu Tiange Zhu Yun +8 位作者 Zhang Ke Huang Jian Wang Hangyu Gao Le Liang Xu Chen Long Wang Jinhui Pang Xiaobo Duan Xingwu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2019年第1期118-126,共9页
OBJECTIVE: To establish a method to analyze the commonalities and characteristics of the aqueous extracts from three Uighur medicines.METHODS: In this study, a combination method of three-stage infrared spectroscopy a... OBJECTIVE: To establish a method to analyze the commonalities and characteristics of the aqueous extracts from three Uighur medicines.METHODS: In this study, a combination method of three-stage infrared spectroscopy and ultra-performance liquid chromatography-time of flight-mass spectra(UPLC-TOF-MS) method was used to analyze the commonalities and characteristics of the aqueous extracts from Hezi(Fructus Chebulae),Maohezi(Terminalia Belliricae Fructus) and Xiqingguo(Chebulae Fructus Immaturus).RESULTS: In Fourier transform-infrared spectroscopy spectra, all three samples showed the characteristic absorption peaks of tannins similarly. According to UPLC-TOF-MS data analysis, the difference of the position and intensity of the peaks at 1713-1707 cm^(-1) in the three samples were related to the difference in the relative content of tannin and pentacyclic triterpenoids. In second derivative infrared spectroscopy spectra, further analysis of the differences in the infrared spectra of the three samples was performed by increasing the apparent resolution. In combination with UPLC-TOF-MS data, some features infrared absorption peaks were assigned.The absorption peaks at 1032-1030 cm^(-1) assigned to the stretching vibration of C-O-C(ether bond)groups of tannins; 1164-1163, 1063-1062, 1009-1005, 904 cm^(-1) attributed to the stretching vibration of C-O(ether bond) and C-O-C groups of glycosidic compounds. 1385-1383 cm^(-1) attributed to the bending vibration of C-H(alkyl hydrogen) of methoxyl group of pentacyclic triterpenoids. Peak 835 cm^(-1) was assigned to the characteristic absorption peak of bending vibration of = C-H groups of pentacyclic triterpenoids. The two dimensional correlation infrared spectroscopy could further quickly distinguish three samples through the dynamic structural information of their chemical components and discrepancy of auto-peaks and cross-peaks intuitively in the range of 1720-419 cm^(-1).CONCLUSION: By comparing the intensity of the infrared characteristic absorption peaks, the main chemical components were assigned, which significantly enriched and perfected the data analysis of the infrared spectra of three Uighur Medicines. It provided a rationale for the identification of medicinal materials with complex and similar chemical components using the three-stage infrared spectroscopy and UPLC-TOF-MS. 展开更多
关键词 TANNINS TERMINALIA Spectrophotometry infrared Chromatography liquid UIGHUR MEDICINE
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An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water
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作者 SHEN Fei XU Yanjuan +1 位作者 WANG Ye CHEN Jing 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第1期30-36,共7页
A method was developed for the detection of seven microcystins(microcystin-LR, RR, YR, LA, LY, LW and LF) in surface water using automatic solid-phase extraction(A-SPE) coupled with ultra-performance liquid chromatogr... A method was developed for the detection of seven microcystins(microcystin-LR, RR, YR, LA, LY, LW and LF) in surface water using automatic solid-phase extraction(A-SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). The automated solid-phase extraction system was used to extract microcystins(MCs) from water samples. UPLC-MS/MS was used to determine MCs concentrations in just 5 min. Method detection limits were from 0.3 to 0.9 ng/L, microcystin recoveries ranged from 83.8% to 114%, and the relative standard deviation(RSD) varied from 5.6% to 12.5%. This analytical approach was found to be simple, highly sensitive, accurate, which required little manual operation. Additionally, to validate this analytical method, A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake, Wuxi, China. 展开更多
关键词 MICROCYSTINS AUTOMATIC SOLID-PHASE extraction ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)
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Enhancing CO_(2) transport with plasma-functionalized ionic liquid membranes
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作者 舒茹晨 许卉 +5 位作者 裴晨霄 王楠 刘新刚 侯剑源 袁圆 张仁熙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期74-81,共8页
The ionic liquid(IL) 1-butyl-3-methylimidazolium tetrafluoroborate treated with radiofrequency plasma is proposed for functionalization and immobilization on polyethersulfone supports to form supported ionic liquid me... The ionic liquid(IL) 1-butyl-3-methylimidazolium tetrafluoroborate treated with radiofrequency plasma is proposed for functionalization and immobilization on polyethersulfone supports to form supported ionic liquid membranes for CO_(2) separation.The effects of treatment time and transmembrane pressure difference on CO_(2) permeance were evaluated.The best gas permeation performance was obtained with a treatment time of 10 min and the transmembrane pressure difference was 0.25 MPa.Characterization of the materials by Fourier transform infrared spectroscopy,x-ray photoelectron spectroscopy and nuclear magnetic resonance spectroscopy demonstrates that the IL is grafted with carboxyl groups and deprotonated through plasma treatment.A preliminary mechanism for the plasma treatment and facilitated transport of CO_(2)has been proposed on this basis. 展开更多
关键词 ionic liquids carbon dioxide supported ionic liquid membranes facilitated transport radiofrequency plasma
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Phosphotungstic acid ionic liquid for efficient photocatalytic desulfurization:Synthesis,application and mechanism
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作者 Chenchao Hu Suhang Xun +5 位作者 Desheng Liu Junjie Zhang Minqiang He Wei Jiang Huaming Li Wenshuai Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期101-111,共11页
An efficient mass transfer process is a critical factor for regulating catalytic activity in a photocatalytic desulfurization system.Herein,a phosphotungstic acid(HPW)active center is successfully composited with a qu... An efficient mass transfer process is a critical factor for regulating catalytic activity in a photocatalytic desulfurization system.Herein,a phosphotungstic acid(HPW)active center is successfully composited with a quaternary ammonium phosphotungstate-based hexadecyltrimethylammonium chloride ionic liquid(CTAC-HPW)by the ion exchange method for the photocatalytic oxidative desulfurization of dibenzothiophene sulfide.The keggin structure of HPW and highly mass transfer performance of organic cations synergistically enhanced the photocatalytic activity towards the effective convertion of dibenzothiophene(DBT)with the excitation of visible light.The deep desulfurization(<10 mg·kg^(-1))is attained within 30 min,and well stability is demonstrated within 25 cycles.Moreover,the CTAC-HPW photocatalyst projects well selectivity to interference from coexisting compounds such as olefins and aromatic hydrocarbons and universality of dibenzothiophenes,for example,4-methyldibenzothiophene(4-MDBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).Ultimately,a possible photocatalytic desulfurization mechanism is proposed according to the Gaschromatography-mass spectrometry(GC-MS),proving that the final product is the corresponding sulfone.The trapping experiment and electron spin resonance(ESR)analysis confirmed that h^(+)and,COOH played critical roles in the oxidation process.The work offers a practicable strategy for efficiently converting DBT to DBTO_(2) with added value. 展开更多
关键词 Photocatalytic desulfurization EXTRACTION Ionic liquid CTAC-HPW
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Method Development and Validation of the Simultaneous Analysis of Methylisothiazolinone, Methylchloroisothiazolinone, Benzisothiazolinone and Bronopol in Washing-Up Liquid
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作者 Etienne Jooken Ruis Amery Boudewijn Meesschaert 《American Journal of Analytical Chemistry》 CAS 2024年第1期43-55,共13页
A method of analysis for the simultaneous determination of methylisothiazolinone (MI), methylchloroisothiazolinone (CMI), benzisothiazolinone (BIT) and Bronopol (BNP) in washing-up liquid was established. The method c... A method of analysis for the simultaneous determination of methylisothiazolinone (MI), methylchloroisothiazolinone (CMI), benzisothiazolinone (BIT) and Bronopol (BNP) in washing-up liquid was established. The method consisted of a gradient HPLC analysis at three different wavelengths. The four compounds could be analyzed with good precision and accuracy. 展开更多
关键词 PRESERVATIVES Analytical Validation METHYLISOTHIAZOLINONE Methylchloroisothiazolinone Benzisothiazolinone BRONOPOL HPLC Washing-Up liquid
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Highly selective extraction of aromatics from aliphatics by using metal chloride-based ionic liquids
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作者 Hui Yu Xiaojia Wu +4 位作者 Chuanqi Geng Xinyu Li Chencan Du Zhiyong Zhou Zhongqi Ren 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期222-229,共8页
The separation of aromatics from aliphatics is essential for achieving maximum exploitation of oil resources in the petrochemical industry.In this study,a series of metal chloride-based ionic liquids were prepared and... The separation of aromatics from aliphatics is essential for achieving maximum exploitation of oil resources in the petrochemical industry.In this study,a series of metal chloride-based ionic liquids were prepared and their performances in the separation of 1,2,3,4-tetrahydronaphthalene(tetralin)/dodecane and tetralin/decalin systems were studied.Among these ionic liquids,1-ethyl-3-methylimidazolium tetrachloroferrate([EMIM][FeCl_(4)])with the highest selectivity was used as the extractant.Density functional theory calculations showed that[EMIM][FeCl_(4)]interacted more strongly with tetralin than with dodecane and decalin.Energy decomposition analysis of[EMIM][FeCl_(4)]-tetralin indicated that electrostatics and dispersion played essential roles,and induction cannot be neglected.The van der Waals forces was a main effect in[EMIM][FeCl_(4)]-tetralin by independent gradient model analysis.The tetralin distribution coefficient and selectivity were 0.8 and 110,respectively,with 10%(mol)tetralin in the initial tetralin/dodecane system,and 0.67 and 19.5,respectively,with 10%(mol)tetralin in the initial tetralin/decalin system.The selectivity increased with decreasing alkyl chain length of the extractant.The influence of the extraction temperature,extractant dosage,and initial concentrations of the system components on the separation performance were studied.Recycling experiments showed that the regenerated[EMIM][FeCl_(4)]could be used repeatedly. 展开更多
关键词 Ionic liquid Aromatic hydrocarbon Aliphatic hydrocarbon Extraction
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Naturally Crosslinked Biocompatible Carbonaceous Liquid Metal Aqueous Ink Printing Wearable Electronics for Multi-Sensing and Energy Harvesting
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作者 King Yan Chung Bingang Xu +3 位作者 Di Tan Qingjun Yang Zihua Li Hong Fu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期148-168,共21页
Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables.Ink printing is desirable for e-textile development using a simple and i... Achieving flexible electronics with comfort and durability comparable to traditional textiles is one of the ultimate pursuits of smart wearables.Ink printing is desirable for e-textile development using a simple and inexpensive process.However,fabricating high-performance atop textiles with good dispersity,stability,biocompatibility,and wearability for high-resolution,large-scale manufacturing,and practical applications has remained challenging.Here,waterbased multi-walled carbon nanotubes(MWCNTs)-decorated liquid metal(LM)inks are proposed with carbonaceous gallium–indium micro-nanostructure.With the assistance of biopolymers,the sodium alginate-encapsulated LM droplets contain high carboxyl groups which non-covalently crosslink with silk sericin-mediated MWCNTs.E-textile can be prepared subsequently via printing technique and natural waterproof triboelectric coating,enabling good flexibility,hydrophilicity,breathability,wearability,biocompatibility,conductivity,stability,and excellent versatility,without any artificial chemicals.The obtained e-textile can be used in various applications with designable patterns and circuits.Multi-sensing applications of recognizing complex human motions,breathing,phonation,and pressure distribution are demonstrated with repeatable and reliable signals.Self-powered and energy-harvesting capabilities are also presented by driving electronic devices and lighting LEDs.As proof of concept,this work provides new opportunities in a scalable and sustainable way to develop novel wearable electronics and smart clothing for future commercial applications. 展开更多
关键词 BIOCOMPATIBLE Conductive ink BIOPOLYMER E-textile Carbonaceous liquid metal
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High-performance liquid metal electromagnetic actuator fabricated by femtosecond laser
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作者 Yiyu Chen Hao Wu +11 位作者 Rui Li Shaojun Jiang Shuneng Zhou Zehang Cui Yuan Tao Xinyuan Zheng Qianqian Zhang Jiawen Li Guoqiang Li Dong Wu Jiaru Chu Yanlei Hu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期511-521,共11页
Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conducto... Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conductor inside soft actuators can reduce the rigidity and enhance the actuation performance and robustness.Despite research efforts,challenges persist in the flexible fabrication of LM soft actuators and in the improvement of actuation performance.To address these challenges,we developed a fast and robust electromagnetic soft microplate actuator based on a laser-induced selective adhesion transfer method.Equipped with unprecedentedly thin LM circuit and customized low Young’s modulus silicone rubber(1.03 kPa),our actuator exhibits an excellent deformation angle(265.25?)and actuation bending angular velocity(284.66 rad·s^(-1)).Furthermore,multiple actuators have been combined to build an artificial gripper with a wide range of functionalities.Our actuator presents new possibilities for designing small-scaleartificial machines and supports advancements in ultrafast soft and miniaturized robotics. 展开更多
关键词 soft actuators femtosecond laser liquid metal
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Ionic liquid-assisted preparation of hydroxyapatite and its catalytic performance for decarboxylation of itaconic acid
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作者 Shutong Pang Hualiang An +1 位作者 Xinqiang Zhao Yanji Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期9-15,共7页
The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal... The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil resource.In order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic performance.The results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of hydroxyapatite.The[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of hydroxyapatite.High fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of hydroxyapatite.The hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic performance.The suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali. 展开更多
关键词 Ionic liquid HYDROXYAPATITE Itaconic acid Methacrylic Decarboxylation reaction
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