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Study of the distribution profile of piperidine alkaloids in various parts of Prosopis juliflora by the application of Direct Analysis in Real Time Mass Spectrometry(DART-MS) 被引量:1
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作者 Shachi SINGH Sanjay Kumar VERMA 《Natural Products and Bioprospecting》 CAS 2012年第5期206-209,共4页
Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of th... Direct Analysis in Real Time Mass Spectrometry(DART-MS)was applied to identify and study the distribution profile of piperidine alkaloids in different parts of Prosopis juliflora,without isolation and separation of the compounds by standard chromatographic techniques.With the help of DART-MS,chemical fingerprint of raw plant parts were generated,which revealed the presence of piperidine alkaloids in leaf,pod and flower.A comparative study of the distribution pattern,showed variation in the presence and distribution of these alkaloids in various parts of P.juliflora.The leaves and pod displayed the largest alkaloid pattern with a total of 12 different alkaloids in each part,whereas only 4 alkaloids were present in flower.Alkaloids:julifloridine,prosopine,prosopinine and prosafrinine were ubiquitously distributed in all the alkaloid rich plant parts.Juliprosopine was pre-eminet alkaloid in leaf,whereas pod and flower displayed copious amounts of julifloridine. 展开更多
关键词 dart-ms chemical fingerprint Prosopis juliflora piperidine alkaloids juliprosopine julifloridine
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DART-MS在中国的应用研究现状 被引量:10
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作者 徐加泉 肖义坡 +1 位作者 陈焕文 张小平 《质谱学报》 EI CAS CSCD 北大核心 2018年第1期120-128,共9页
敞开式离子化质谱(ambient ionization mass spectrometry,AIMS)技术因其具有实时、原位分析等特点,已成为质谱学领域的一个研究热点。实时直接质谱分析(direct analysis in real-time mass spectrometry,DART-MS)作为一种典型的直接质... 敞开式离子化质谱(ambient ionization mass spectrometry,AIMS)技术因其具有实时、原位分析等特点,已成为质谱学领域的一个研究热点。实时直接质谱分析(direct analysis in real-time mass spectrometry,DART-MS)作为一种典型的直接质谱分析技术,可在开放环境中实现样品的快速分析,具有性能稳定、操作简单、分析快速等优点,自2005年被报道以来,便引起了广泛的关注。本文从DART电离源的工作原理以及近2年DART-MS在环境分析、食品药品安全、生物医学分析以及公共安全等领域的应用研究进行了评述,并对其发展方向进行了展望。 展开更多
关键词 dart-ms 直接质谱分析 环境分析 食品药品安全 生物医学分析 公共安全
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基于DART-MS技术的人参皂苷结构分析 被引量:5
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作者 闫福源 许宁 +5 位作者 王任晶 崔长升 齐滨 刘淑莹 王洋 刘莉 《长春中医药大学学报》 2018年第6期1058-1062,共5页
目的建立一种可以对人参皂苷结构进行定性检测的方法。方法采用实时直接分析(DART)离子源结合四极杆串联飞行时间质谱(Q-TOF-MS)技术对人参皂苷结构进行分析研究。结果确定了DART离子源以氦气为载气,氦气流速2.0 L/min,氦气温度为400℃... 目的建立一种可以对人参皂苷结构进行定性检测的方法。方法采用实时直接分析(DART)离子源结合四极杆串联飞行时间质谱(Q-TOF-MS)技术对人参皂苷结构进行分析研究。结果确定了DART离子源以氦气为载气,氦气流速2.0 L/min,氦气温度为400℃,毛细管电压为3 500 V,锥孔电压为65 V,碎裂电压150 V,对人参皂苷结构进行分析研究。结论该技术具有通用性强、耐用性好、检测灵敏度高、操作简单等特点,可以对不同的人参皂苷及人参皂苷同分异构体之间进行区分,还可以检测含有人参皂苷的样品,对该领域的进一步研究有一定的重要意义。 展开更多
关键词 dart-ms技术 人参皂苷 结构分析
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DART-MS/MS法测定烟草及烟草制品中的烟碱 被引量:5
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作者 吴亿勤 刘秀明 +4 位作者 秦云华 张承明 许永 杨亚玲 李超 《烟草科技》 EI CAS CSCD 北大核心 2017年第8期46-51,74,共7页
为实时在线检测烟草及烟草制品中的烟碱,通过优化萃取溶剂种类、萃取溶剂用量、进样速率等参数,建立了基于实时直接分析(DART)新型原位电离技术和质谱(MS)技术测定烟草及烟草制品中烟碱含量(质量分数)的方法。采用该方法测定了5种成品... 为实时在线检测烟草及烟草制品中的烟碱,通过优化萃取溶剂种类、萃取溶剂用量、进样速率等参数,建立了基于实时直接分析(DART)新型原位电离技术和质谱(MS)技术测定烟草及烟草制品中烟碱含量(质量分数)的方法。采用该方法测定了5种成品卷烟及5种烟叶样品,并与连续流动法检测结果进行了对比。结果表明:(1)用30 mL超纯水萃取、进样速率为0.6 mm/s时效果较好,20 s即可完成样品检测。(2)方法线性范围为0.01~2.00 mg/mL,R2为0.999 1,回收率为98.5%~102.3%,检出限和定量限分别为6.05和20.17 ng/mL。(3)DART-MS/MS法与连续流动法测定结果相对偏差为0.24%~2.74%。该方法快速、可靠,适用于烟草及烟草制品中烟碱的实时在线检测。 展开更多
关键词 dart-ms/MS 烟草 烟草制品 烟碱
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DART-MS/MS法简介及农药残留检测方法综述 被引量:2
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作者 高芸芸 《甘肃科技》 2019年第2期43-45,共3页
农药可以杀灭病虫害,对农业生产同样有积极意义。但是农药残留超标对人体健康有重大影响。DART-MS/MS作为近年来兴起的一种检测方法,因为其具有绿色,环保,简单,快速的优点,是国外研究的热点,广泛应用于各大检测领域;但是国内的相关研究... 农药可以杀灭病虫害,对农业生产同样有积极意义。但是农药残留超标对人体健康有重大影响。DART-MS/MS作为近年来兴起的一种检测方法,因为其具有绿色,环保,简单,快速的优点,是国外研究的热点,广泛应用于各大检测领域;但是国内的相关研究屈指可数。本文对DART-MS/MS法加以介绍,并对农药残留的检测现状加以综述。 展开更多
关键词 分析化学 dart-ms/MS 农药残留
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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator 被引量:1
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作者 Yang Zhang Sheng-Quan Yan +36 位作者 Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期136-143,共8页
The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides... The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated. 展开更多
关键词 Accelerator mass spectrometry Wien filter Isobar separation SUPERNOVAE Chang'e-5 lunar samples
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用实时直接分析质谱法(DART-MS)快速测定桑叶中的γ-氨基丁酸含量 被引量:7
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作者 李无双 郎文成 +2 位作者 马琳 李龙 武国华 《蚕业科学》 CAS CSCD 北大核心 2018年第4期567-572,共6页
γ-氨基丁酸(γ-aminobutyric acid,GABA)是桑叶中具有多种药理作用的重要组分之一。为了快速、准确测定桑叶中的GABA含量,建立了基于实时直接分析电离源-串联三重四极杆质谱(DART-MS)的桑叶GABA定性和定量分析方法。在DART离子源... γ-氨基丁酸(γ-aminobutyric acid,GABA)是桑叶中具有多种药理作用的重要组分之一。为了快速、准确测定桑叶中的GABA含量,建立了基于实时直接分析电离源-串联三重四极杆质谱(DART-MS)的桑叶GABA定性和定量分析方法。在DART离子源和质量分析器同为正离子的模式下,采用选择反应监测模式(SRM)并选取m/z 104→87为定量离子对,以其峰面积(y)进行定量分析,所得线性回归方程为y=4 552 210.19x-11 927 811.70,线性系数R-2=0.998,且在GABA溶液质量浓度(x)为2.50-40.00μg/m L范围内的线性关系良好。对3种质量浓度(7.82、4.14、2.78μg/m L)桑叶样品提取液进行测定的相对标准偏差(RSD)分别为3.98%、5.60%、2.28%,表明该方法的精密度良好;加标回收率在85.60%-97.47%之间。应用DART-MS法对来源于江、浙、皖蚕区的6个桑品种的桑叶样品进行检测,桑叶提取液样品中的GABA质量浓度从高到低的桑品种依次为湖桑32号(7.82μg/m L±0.31μg/m L,江苏海安)、强桑2号(7.44μg/m L±0.21μg/m L,浙江杭州)、强桑1号(7.14μg/m L±0.50μg/m L,杭州)、农桑14号(5.88μg/m L±0.30μg/m L,杭州)、育711号(5.81μg/m L±0.18μg/m L,安徽合肥)、农桑14号(4.25μg/m L±0.29μg/m L,浙江海宁)。建立的DART-MS法用于测定桑叶中的GABA含量,具有简单、快速且灵敏度高等特点。 展开更多
关键词 实时直接分析质谱 桑叶 Γ-氨基丁酸 精密度 加标回收率
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Mass Spectrometry-based Deep Coverage Proteome:Evaluation of Cellular Protein Extraction Methods
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作者 XU Xia QIN Weida +3 位作者 LI Ruomeng WANG Qianqian LIU Ning LI Gongyu 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期98-107,共10页
The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample pre... The current study comprehensively evaluates four different protein extraction methods based on urea,sodium dodecyl sulfate(SDS),anionic surfactants(BT),and total RNA extractor(Trizol),aiming to optimize the sample preparation workflow for mass spectrometry-based proteomics.Using HeLa cells as an example,we found that the method employing the mass spectrometry-compatible surfactant BT reagent significantly reduces the total time consumed for protein extraction and minimizes protein losses during the sample preparation process.Further integrating the four protein extraction methods,we identified over 7000 proteins from HeLa cells without relying on pre-fractionation techniques,and 2990 of them were quantified using label-free quantification.It is worth noting that the BT and SDS methods demonstrate higher efficiency in extracting membrane proteins,while the Urea and Trizol methods are more effective in extracting proteins from nuclear and cytoplasmic fractions.In summary,this study provides a novel solution for deep proteome coverage,particularly in the context of cellular protein extraction,by integrating mass spectrometry-compatible surfactants with traditional extraction methods to effectively enhance protein identification numbers. 展开更多
关键词 SURFACTANT Protein extraction PROTEOMICS Mass spectrometry
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Bacterial Protein Profiling——Comparison of Three Mass Spectrometry Methodologies
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作者 JIANG Yan CHEN Yanlin +4 位作者 SONG Gaoyu CHEN Yanyan BAI Jing ZHU Yingdi LI Juan 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第11期158-173,共16页
Profiling the protein composition of bacteria is essential for understanding their biology,physiology and interaction with environment.Mass spectrometry has become a pivotal tool for protein analysis,facilitating the ... Profiling the protein composition of bacteria is essential for understanding their biology,physiology and interaction with environment.Mass spectrometry has become a pivotal tool for protein analysis,facilitating the examination of expression levels,molecular masses and structural modifications.In this study,we compared the performance of three widely-used mass spectrometry methods,i.e.,matrix-assisted laser desorption/ionization(MALDI)protein fingerprinting,top-down proteomics and bottom-up proteomics,in the profiling of bacterial protein composition.It was revealed that bottom-up proteomics provided the highest protein coverage and exhibited the greatest protein profile overlap between bacterial species.In contrast,MALDI protein fingerprinting demonstrated superior detection reproducibility and effectiveness in distinguishing between bacterial species.Although top-down proteomics identified fewer proteins than bottom-up approach,it complemented MALDI fingerprinting in the discovery of bacterial protein markers,both favoring abundant,stable,and hydrophilic bacterial ribosomal proteins.This study represents the most systematic and comprehensive comparison of mass spectrometry-based protein profiling methodologies to date.It provides valuable guidelines for the selection of appropriate profiling strategies for specific analytical purposes.This will facilitate studies across various fields,including infection diagnosis,antimicrobial resistance detection and pharmaceutical target discovery. 展开更多
关键词 BACTERIA Protein profiling Mass spectrometry
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Ultra-soft Desorption Assisted Mass Spectrometry using Picosecond Infrared Laser for the Detection of lons in the Liquid Surface
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作者 Ziyuan Li Yue Wang +2 位作者 Tiantian Tong Ziwei Chen Shan Xi Tian 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期461-464,I0093,共5页
To identify the species in liquid surface using mass spectrometry,we must eliminate or reduce interferences during the vaporization or desorption of the species from the liquid surface.It is much more challenging to i... To identify the species in liquid surface using mass spectrometry,we must eliminate or reduce interferences during the vaporization or desorption of the species from the liquid surface.It is much more challenging to isolate the ionic,larger species from the liquid surface,because of the frangible structures and the higher solvation energies of those species.Here we demonstrate a new mass spectrometry in which the ionic species at the liquid surface can be desorbed with ultrasoft infrared picosecond laser pulses while the liquid surface is not breached.This laser desorption assisted mass spectrometry is not only a powerful tool to detect the fragile species but also promising to investigate vibrational energy transfer dynamics in the liquid surface. 展开更多
关键词 Ultrasoft desorption Infrared laser Picosecond pulse Mass spectrometry Liquid surface
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Improved isochronous mass spectrometry with tune measurement
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作者 Han-Yu Deng Yuan-Ming Xing +5 位作者 Xu Zhou Yu-Hu Zhang Xin-Liang Yan Jin-Yang Shi Ting Liao Meng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期174-181,共8页
In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.Ho... In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.However,the resolution of T inevitably deteriorates due to the magnetic rigidity spread of the ions,limiting the mass-resolving power.In this study,we used the betatron tunes Q(the number of betatron oscillations per revolution)of the ions and established a correlation between T and Q.From this correlation,T was transformed to correspond to a fixed Q with higher resolution.Using these transformed T values,the masses of ^(63)Ge,^(65)As,^(67)Se,and ^(71)Kr agreed well with the mass values measured using the newly developed IMS(Bρ-IMS).We also studied the systematics of Coulomb displacement energies(CDEs)and found that anomalous staggering in CDEs was eliminated using new mass values.This method of T transformation is highly effective for conventional IMS equipped with a single time-of-flight detector. 展开更多
关键词 Isochronous Mass spectrometry Storage ring TUNE Natural chromaticity Nuclear mass measurement
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DART-MS/MS快速检测食品中非法添加的N-苄基他达拉非等7种新型PDE-5型抑制剂 被引量:1
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作者 任静 董培智 赵丽红 《食品与药品》 CAS 2023年第4期329-333,共5页
目的将实时直接分析离子源(direct analysis in real time,DART)与三重四极杆质谱联用,建立食品中非法添加PDE-5型抑制剂的快速筛查方法。方法3种不同基质样品加入乙腈振摇10 s后,设进样速率0.2 mm/s,进样体积4μl,选择DART离子源,离子... 目的将实时直接分析离子源(direct analysis in real time,DART)与三重四极杆质谱联用,建立食品中非法添加PDE-5型抑制剂的快速筛查方法。方法3种不同基质样品加入乙腈振摇10 s后,设进样速率0.2 mm/s,进样体积4μl,选择DART离子源,离子化温度450℃,在正离子、多反应监测(MRM)下进行检测。结果该方法7种物质的检出限为0.025~12.5μg/g,检出阳性样品4种,分别非法添加羟基卡巴地那非、环己基去甲他达拉非、N-苄基他达拉非和N-苯基丙氧苯基卡巴地那非。结论该方法样品前处理简单,分析速度快,定性准确,环境污染小,能满足食品中非法添加PDE-5型抑制剂的快速筛查要求。 展开更多
关键词 实时直接分析 三重四极杆质谱 食品 PDE-5抑制剂 非法添加
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Determination of 14 Organophosphorus Pesticide Residues in Mutton by Gel Permeation Chromatography-Gas Chromatography-Mass Spectrometry(GPC-GC-MS)
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作者 Junpeng ZHAO Richard Avoi +2 位作者 Azman Bin Atil@Azmi Jiao CHEN Ling YUN 《Agricultural Biotechnology》 2024年第3期28-30,33,共4页
[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga... [Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton. 展开更多
关键词 MUTTON Gas chromatography-mass spectrometry Gel permeation chromatography ORGANOPHOSPHORUS Pesticide residue
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Research on the Upper Limit of Accuracy for Predicting Theoretical Tandem Mass Spectrometry
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作者 Changjiu He Xiaoyu Wang +1 位作者 Mingming Lyu Xinye Bian 《Journal of Computer and Communications》 2024年第3期184-195,共12页
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy... In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions. 展开更多
关键词 Tandem Mass spectrometry Spectral Prediction Theoretical Limit
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Chemical profiling of bioactive compounds in the methanolic extract of wild leaf and callus of Vitex negundo using gas chromatographymass spectrometry
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作者 Gunjan Garg Alok Bharadwaj +1 位作者 Shweta Chaudhary Veena Gupta 《World Journal of Experimental Medicine》 2024年第1期78-87,共10页
BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.neg... BACKGROUND The investigation of plant-based therapeutic agents in medicinal plants has revealed their presence in the extracts and provides the vision to formulate novel techniques for drug therapy.Vitex negundo(V.negundo),a perennial herb belonging to the Varbanaceae family,is extensively used in conventional medication.AIM To determine the existence of therapeutic components in leaf and callus extracts from wild V.negundo plants using gas chromatography-mass spectrometry(GCMS).METHODS In this study,we conducted GC-MS on wild plant leaf extracts and correlated the presence of constituents with those in callus extracts.Various growth regulators such as 6-benzylaminopurine(BAP),2,4-dichlorophenoxyacetic acid(2,4-D),α-naphthylacetic acid(NAA),and di-phenylurea(DPU)were added to plant leaves and in-vitro callus and grown on MS medium.RESULTS The results clearly indicated that the addition of BAP(2.0 mg/L),2,4-D(0.2 mg/mL),DPU(2.0 mg/L)and 2,4-D(0.2 mg/mL)in MS medium resulted in rapid callus development.The plant profile of Vitex extracts by GC-MS analysis showed that 24,10,and 14 bioactive constituents were detected in the methanolic extract of leaf,green callus and the methanolic extract of white loose callus,respectively.CONCLUSION Octadecadienoic acid,hexadecanoic acid and methyl ester were the major constituents in the leaf and callus methanolic extract.Octadecadienoic acid was the most common constituent in all samples.The maximum concentration of octadecadienoic acid in leaves,green callus and white loose callus was 21.93%,47.79%and 40.38%,respectively.These findings demonstrate that the concentration of octadecadienoic acid doubles in-vitro compared to in-vivo.In addition to octadecadienoic acid;butyric acid,benzene,1-methoxy-4-(1-propenyl),dospan,tridecanedialdehyde,methylcyclohexenylbutanol,chlorpyrifos,n-secondary terpene diester,anflunine and other important active compounds were also detected.All these components were only available in callus formed in-vitro.This study showed that the callus contained additional botanical characteristics compared with wild plants.Due to the presence of numerous bioactive compounds,the medical use of Vitex for various diseases has been accepted and the plant is considered an important source of therapeutics for research and development. 展开更多
关键词 Leaf extracts Callus extracts Methanolic extract Octadecadienoic acid Hexadecanoic acid Methyl ester Gas chromatography-mass spectrometry analysis
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Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry
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作者 Fang LI Xuemei LI +3 位作者 Xiangang LI Sining LIU Sha LIU Ying WANG 《Plant Diseases and Pests》 2024年第1期28-32,共5页
[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f... [Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food. 展开更多
关键词 Animal derived food α_(2)-receptor agonist Solid-phase extraction Ultra-high performance liquid phase-triple quadrupole/linear ion trap composite mass spectrometry
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A Fragmentation Mechanism of Homemade Explosive TMDD Using DART-MS and Isotopic Labeling
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作者 Alexander Pedroza Zarate Fredy Colpas-Castillo +2 位作者 Daniel J.Alcazar Franco Wilman A.Cabrera-Lafaurie Eduardo A.Espinosa-Fuentes 《火炸药学报》 CSCD 北大核心 2018年第1期16-20,30,共6页
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三七治疗骨关节炎机制:基于UHPLC-QE-MS、网络药理学及分子动力学模拟
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作者 陈跃平 陈锋 +2 位作者 彭清林 陈荟伊 董盼锋 《中国组织工程研究》 CAS 北大核心 2025年第8期1751-1760,共10页
背景:课题组前期研究发现三七能够修复骨细胞的形态结构,对于治疗骨关节炎具有良好的应用前景,但目前对于三七的具体作用机制尚不清楚。目的:采用超高效液相色谱-四极杆-静电场轨道阱串联质谱(ultra-high performance liquid chromatogr... 背景:课题组前期研究发现三七能够修复骨细胞的形态结构,对于治疗骨关节炎具有良好的应用前景,但目前对于三七的具体作用机制尚不清楚。目的:采用超高效液相色谱-四极杆-静电场轨道阱串联质谱(ultra-high performance liquid chromatography-Q exactive-mass spectrometry,UHPLC-QE-MS)技术鉴定三七的主要成分,并结合网络药理学、分子对接和分子动力学模拟探究三七治疗骨关节炎的作用机制。方法:利用UHPLC-QE-MS技术鉴定三七的主要成分后,运用TCMSP数据库筛选活性成分,通过TCMSP和Uniprot数据库查找活性成分靶点,通过疾病数据库筛选骨关节炎靶点。在药物靶点与疾病靶点取交集后,导入STRING数据库和Cytoscape软件构建蛋白互作网络筛选关键靶点,通过“活性成分-作用靶点”网络筛选关键活性成分。再对关键靶点进行富集分析,并对关键活性成分和关键靶点进行分子对接验证,最后选取结合能最低的结果进行分子动力学模拟。结果与结论:①在三七溶液中共鉴定出57种活性成分,成分靶点与疾病靶点交集50个,关键活性成分5个(槲皮素、熊脱氧胆酸、山奈酚、柚皮素和红藻氨酸),关键靶点5个(白细胞介素6、基质金属蛋白酶9、白细胞介素1β、白蛋白和趋化因子配体2);②基因本体功能富集642个条目,其中620个条目代表生物过程,21个条目代表分子功能,1个条目代表细胞成分;京都基因与基因组百科全书通路分析63条通路,主要涉及雌激素信号通路、白细胞介素17信号通路和高糖基化终末产物-高糖基化终末产物受体信号通路;③分子对接显示关键活性成分和关键靶点结合活性良好,分子动力学模拟提示槲皮素和基质金属蛋白酶9间的相互作用稳定;④对三七成分进行了较全面研究,初步阐明了其药效物质基础,预测三七可通过多组分、多靶点、多途径和多通路发挥抗炎、软骨保护和免疫调节作用来治疗骨关节炎。 展开更多
关键词 三七 骨关节炎 分子动力学模拟 质谱 分子对接 网络药理学
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西洋参中皂苷类成分表征和炮制导致成分转化的研究进展
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作者 刘忠英 李瑜 +2 位作者 刘舒 后宗 汪戎锦 《吉林大学学报(理学版)》 北大核心 2025年第1期229-240,共12页
西洋参富含多种药理活性物质,具有保护心血管系统、改善神经系统疾病和降血糖等多种药理作用,目前对西洋参中皂苷类成分的结构表征及炮制转化研究取得了显著进展.总结概括西洋参中皂苷类活性成分的分类和分布、现代主流分析技术以及炮... 西洋参富含多种药理活性物质,具有保护心血管系统、改善神经系统疾病和降血糖等多种药理作用,目前对西洋参中皂苷类成分的结构表征及炮制转化研究取得了显著进展.总结概括西洋参中皂苷类活性成分的分类和分布、现代主流分析技术以及炮制加工对皂苷类成分的转化机制,为西洋参皂苷类成分的深入挖掘和创新炮制技术等提供有效的技术支撑和指导方法,从而扩大其在医疗和保健等方面的应用. 展开更多
关键词 西洋参 皂苷 串联质谱 炮制加工
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基于顶空-固相微萃取-气相色谱-质谱和顶空-气相色谱-离子迁移谱技术结合化学计量法分析芜菁冻干片挥发性成分
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作者 岳丽 张英仙 +4 位作者 祖力皮牙·买买提 王佳敏 毛红艳 于明 热依拉木·海力力 《食品与发酵工业》 北大核心 2025年第2期300-310,共11页
为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱... 为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱-离子迁移谱(headspace gas chromatography-ion mobility spectrometry,HS-GC-IMS)对紫色、黄色和白色3种芜菁冻干片的VOCs进行分析,并结合主成分分析(principal component analysis,PCA)和偏最小二乘判别法(partial least squares-discriminant analysis,PLS-DA)等化学计量法探究不同品种芜菁冻干片挥发性成分的差异。结果表明,通过HS-SPME-GC-MS共解析出96种VOCs,包括醛类、醇类、酮类、含硫化合物、酯类、酸类等化合物,其中含硫化合物和酯类为芜菁冻干片中相对含量最高的化合物种类;HS-GC-IMS共解析出94种VOCs,包括醛类、酯类、酮类及含硫化合物等挥发性成分。HS-SPME-GC-MS和HS-GC-IMS检出的挥发性物质种类和含量存在差异,共有VOCs有15种,二者结果互为补充,结合使用可以较全面系统地表征芜菁冻干片的挥发性成分。PCA和PLS-DA结果表明,2种方法均能够有效区分3种芜菁冻干片。通过变量投影重要度分别筛选了59种和23种差异VOCs,该结果可为芜菁冻干片VOCs的差异分析提供参考方法。 展开更多
关键词 芜菁冻干片 挥发性有机物 顶空-固相微萃取-气相色谱-质谱 顶空-气相色谱-离子迁移谱 变量投影重要度
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