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Solid-phase microextraction of endogenous metabolites from intact tissue validated using a Biocrates standard reference method kit 被引量:1
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作者 Runshan Will Jiang Karol Jaroch Janusz Pawliszyn 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第1期55-62,共8页
Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the ... Improved analytical methods for the metabolomic profiling of tissue samples are constantly needed.Currently,conventional sample preparation methods often involve tissue biopsy and/or homogenization,which disrupts the endogenous metabolome.In this study,solid-phase microextraction(SPME)fibers were used to monitor changes in endogenous compounds in homogenized and intact ovine lung tissue.Following SPME,a Biocrates AbsoluteIDQ assay was applied to make a downstream targeted metabolomics analysis and confirm the advantages of in vivo SPME metabolomics.The AbsoluteIDQ kit enabled the targeted analysis of over 100 metabolites via solid-liquid extraction and SPME.Statistical analysis revealed significant differences between conventional liquid extractions from homogenized tissue and SPME results for both homogenized and intact tissue samples.In addition,principal component analysis revealed separated clustering among all the three sample groups,indicating changes in the metabolome due to tissue homogenization and the chosen sample preparation method.Furthermore,clear differences in free metabolites were observed when extractions were performed on the intact and homogenized tissue using identical SPME procedures.Specifically,a direct comparison showed that 47 statistically distinct metabolites were detected between the homogenized and intact lung tissue samples(P<0.05)using mixed-mode SPME fibers.These changes were probably due to the disruptive homogenization of the tissue.This study's findings highlight both the importance of sample preparation in tissue-based metabolomics studies and SPME's unique ability to perform minimally invasive extractions without tissue biopsy or homogenization while providing broad metabolite coverage. 展开更多
关键词 solid-phase microextraction Solvent extraction Metabolomics Sample preparation In vivo sampling
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation Regional large-scale Online recognition Feature extraction method
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Solid-phase extraction of trace Au(Ⅲ) with SDG and determination by the catalytic spectrophotometric method 被引量:2
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作者 LI Huizhi ZHAI Yubo 《Rare Metals》 SCIE EI CAS CSCD 2008年第6期560-565,共6页
The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ... The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ((NH4)2S2O8) with nitrilo triacetic acid as an activator in microemulsion and H2SO4 medium. Under optimum conditions, there was the linearity of the calibration curve in the concentration range from 0 to 20 μg/L Au(Ⅲ) at 520 nm. The relative standard deviation was 3.0% with a correlation coefficient of 0.9986. The detection limit achieved was 9.75 × 10^-5 μg/mL. A new method using a column packed with sulfhydryl dextrose gel (SDG) as a solid-phase extractant has been developed for the preconcentration and separation of Au(Ⅲ) ions. The method has been applied to the determination of trace gold with satisfactory results. 展开更多
关键词 analytical chemistry catalytic kinetic spectrophotometric method solid-phase extraction gold(Ⅲ)
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Multiresidue Method for Determination of 67 Pesticides in Water Samples Using Solid-Phase Extraction with Centrifugation and Gas Chromatography-Mass Spectrometry 被引量:3
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作者 Abir Kouzayha Abdul Rahman Rabaa +3 位作者 Mohamad Al Iskandarani Daniel Beh Hélène Budzinski Farouk Jaber 《American Journal of Analytical Chemistry》 2012年第3期257-265,共9页
A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 a... A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 and Oasis HLB. Parameters that influence the extraction efficiency such as the eluent volume, the sample loading volume, the addition of organic solvent to water sample, sorbent drying and elute concentration were optimized. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 2 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under the optimized conditions, this method showed good recoveries higher than 65% - 68% for the 67 analyzed pesticides using the C18 and HLB cartridges with relative standard deviations lower than 9.7% - 12.3%. Limits of quantification were between 2 and 20 ng.L–1. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples. 展开更多
关键词 MULTI-RESIDUE PESTICIDES solid-phase extraction CENTRIFUGATION Gas Chromatography-Mass SPECTROMETRY
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Phase equilibrium data prediction and process optimizationin butadiene extraction process
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作者 Baowei Niu Yanjie Yi +5 位作者 Yuwen Wei Fuzhen Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期1-12,共12页
In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene p... In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene production by acetonitrile.The accuracy of five prediction methods,UNIFAC(UNIQUAC Functional-group Activity Coefficients),UNIFAC-LL,UNIFAC-LBY,UNIFAC-DMD and COSMO-RS,applied to the butadiene extraction process was verified using partial phase equilibrium data.The results showed that the UNIFAC-DMD method had the highest accuracy in predicting phase equilibrium data for the missing system.COSMO-RS-predicted multiple systems showed good accuracy,and a large number of missing phase equilibrium data were estimated using the UNIFAC-DMD method and COSMO-RS method.The predicted phase equilibrium data were checked for consistency.The NRTL-RK(non-Random Two Liquid-Redlich-Kwong Equation of State)and UNIQUAC thermodynamic models were used to correlate the phase equilibrium data.Industrial device simulations were used to verify the accuracy of the thermodynamic model applied to the butadiene extraction process.The simulation results showed that the average deviations of the simulated results using the correlated thermodynamic model from the actual values were less than 2%compared to that using the commercial simulation software,Aspen Plus and its database.The average deviation was much smaller than that of the simulations using the Aspen Plus database(>10%),indicating that the obtained phase equilibrium data are highly accurate and reliable.The best phase equilibrium data and thermodynamic model parameters for butadiene extraction are provided.This improves the accuracy and reliability of the design,optimization and control of the process,and provides a basis and guarantee for developing a more environmentally friendly and economical butadiene extraction process. 展开更多
关键词 Butadiene extraction Phase equilibrium data Prediction methods Thermodynamic modeling Process simulation
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Robotic natural orifice specimen extraction surgery I-type F method vs conventional robotic resection for lower rectal cancer 被引量:2
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作者 Fang Tao Dong-Ning Liu +4 位作者 Peng-Hui He Xin Luo Chi-Ying Xu Tai-Yuan Li Jin-Yuan Duan 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2142-2153,共12页
BACKGROUND Robotic resection using the natural orifice specimen extraction surgery I-type F method(R-NOSES I-F)is a novel minimally invasive surgical strategy for the treatment of lower rectal cancer.However,the curre... BACKGROUND Robotic resection using the natural orifice specimen extraction surgery I-type F method(R-NOSES I-F)is a novel minimally invasive surgical strategy for the treatment of lower rectal cancer.However,the current literature on this method is limited to case reports,and further investigation into its safety and feasibility is warranted.AIM To evaluate the safety and feasibility of R-NOSES I-F for the treatment of low rectal cancer.METHODS From September 2018 to February 2022,206 patients diagnosed with low rectal cancer at First Affiliated Hospital of Nanchang University were included in this retrospective analysis.Of these patients,22 underwent R-NOSES I-F surgery(RNOSES I-F group)and 76 underwent conventional robotic-assisted low rectal cancer resection(RLRC group).Clinicopathological data of all patients were collected and analyzed.Postoperative outcomes and prognoses were compared between the two groups.Statistical analysis was performed using SPSS software.RESULTS Patients in the R-NOSES I-F group had a significantly lower visual analog score for pain on postoperative day 1(1.7±0.7 vs 2.2±0.6,P=0.003)and shorter postoperative anal venting time(2.7±0.6 vs 3.5±0.7,P<0.001)than those in the RLRC group.There were no significant differences between the two groups in terms of sex,age,body mass index,tumor size,TNM stage,operative time,intrao-perative bleeding,postoperative complications,or inflammatory response(P>0.05).Postoperative anal and urinary functions,as assessed by Wexner,low anterior resection syndrome,and International Prostate Symptom Scale scores,were similar in both groups(P>0.05).Long-term follow-up revealed no significant differences in the rates of local recurrence and distant metastasis between the two groups(P>0.05).CONCLUSION R-NOSES I-F is a safe and effective minimally invasive procedure for the treatment of lower rectal cancer.It improves pain relief,promotes gastrointestinal function recovery,and helps avoid incision-related complications. 展开更多
关键词 Robotic surgery Natural orifice specimen extraction surgery Lower rectal cancer Robotic resection using the natural orifice specimen extraction surgery I-type F method
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Effects of dietary oil sources and fat extraction methods on apparent and standardized ileal digestibility of fat and fatty acids in growing pigs
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作者 Lu Wang Wenjun Gao +3 位作者 Junyan Zhou Huangwei Shi Tenghao Wang Changhua Lai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期760-770,共11页
Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,... Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extraction methods on the calculated values for endogenous loss and digestibility of fat.Methods:Twenty-two barrows(initial body weight:32.1 ± 2.3 kg) were surgically fitted with a T-cannula in the distal ileum,and allotted to 1 of 11 experimental diets in a 4-period Youden Square design.A fat-free diet was formulated using cornstarch,soy protein isolate and sucrose.Ten oil-added diets were formulated by adding 6% of dietary oil sources to the fat-free diet at the expense of cornstarch.All diets contained 26% sugar beet pulp and 0.40% chromic oxide.Results:The endogenous loss of ether extract(EE) was lower than that of acid-hydrolyzed fat(AEE;P < 0.01).There were significant differences in the AID and SID of fat and saturated fatty acids across the dietary oil sources(P < 0.05).The SID of AEE for palm oil was lower than that of sunflower oil,corn oil,canola oil,rice oil and flaxseed oil(P < 0.01).The AID and SID of fat ranged from 79.65% to 86.97% and from 91.14% to 99.18%.Although the AID of EE was greater than that of AEE(P < 0.01),there was no significant difference in SID of EE and AEE except for palm oil.The ratio of unsaturated to saturated fatty acids(U/S) had a positive correlation with SID of fat(P < 0.05),whereas C16:0 and long chain saturated fatty acids(LSFA) were significant negatively correlated with SID of fat(P < 0.01).The best-fit equation to predict SID of fat was SID AEE = 102.75-0.15 × LSFA-0.74 × C18:0-0.03 × C18:1(Adjusted coefficient of determination = 0.88,P < 0.01).Conclusions:When calculating the SID of fat,the EE content of the samples can be analyzed using the direct extraction method,whereas the acid hydrolysis procedure should be used to determine the AID of fat.Fat digestibility of dietary oils was affected by their fatty acid composition,especially by the contents of C16:0,LSFA and U/S. 展开更多
关键词 Fat extraction methods Fatty acids Growing pigs Ileal digestibility Oil sources
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Optimization of extraction method for quantitative analysis of Si/Al in soil phytoliths
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作者 Yongsheng Chu Yue Xia +1 位作者 Xiaoying Li Fushun Wang 《Acta Geochimica》 EI CAS CSCD 2023年第6期1007-1016,共10页
Elemental information carried by phytoliths plays a crucial indicative role in geochemical research.For instance,it serves as an indicator of the carbon pool effect in phytoliths and aids in the elucidation of silicon... Elemental information carried by phytoliths plays a crucial indicative role in geochemical research.For instance,it serves as an indicator of the carbon pool effect in phytoliths and aids in the elucidation of silicon sources.However,early extraction methods for soil phytoliths primarily focused on obtaining their morphological and quantitative information,lacking efficient techniques for quantitative elemental analysis.In this study,we aimed to extract Si/Al information from soil phytoliths.Considering the need for complete extraction of phytolith,six extraction methods were developed and further by alkaline dissolution to determine Si/Al.Six methods were compared in terms of enrichment capacity,the weight of extracted phytoliths,and Si/Al differences.The results indicated that the addition of Ammonia-Catechol in the commonly used heavy liquid flotation method effectively improved phytolith extraction capability and the accuracy of Si/Al results.Additionally,the inclusion of an acetic acid step before alkaline dissolution further removed surface-adsorbed impurities and enhanced the analytical quality of Si/Al in phytolith.The comparison of the data in this study with other published data shows that our method is relatively robust.The improved method proposed in this study can provide a new idea for the quantitative analysis of other elements in soil phytoliths. 展开更多
关键词 Soil phytolith extraction method Silica–aluminum ratio Ammonia–Catechol
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Optimization of Supercritical Extraction Process of Laoshan Black Tea by Response Surface Methodology
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作者 Yongxin LIU Zhiguang LIU +11 位作者 Zengyu WANG Shuai ZHANG Guofeng YU Jianhong SUN Shoutao CAO Qiulin LIU Xulun WEI Cuishu LENG Fuhua MA Xuegang LI Yinlong WANG Shoujie NIE 《Agricultural Biotechnology》 CAS 2023年第1期98-101,共4页
[Objectives]Laoshan black tea was subjected to supercritical CO_(2) extraction. [Methods]The extraction conditions of Laoshan black tea were studied by an orthogonal experiment and optimized by response surface method... [Objectives]Laoshan black tea was subjected to supercritical CO_(2) extraction. [Methods]The extraction conditions of Laoshan black tea were studied by an orthogonal experiment and optimized by response surface methodology. [Results] The optimum extraction conditions of black tea extract by supercritical CO_(2) extraction were as follows: extraction pressure 23.53 MPa, extraction time 1.73 h, and extraction temperature 49.75 ℃, with which the extract yield could reach 5.15% theoretically. [Conclusions] Based on the traditional extraction process, a supercritical extraction method optimized by response surface methodology and a unique extraction process were formed, which enriches the extraction processes and methods of natural raw materials. 展开更多
关键词 Laoshan black tea Supercritical extraction Response surface method
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Microplastics in Marine Environment: Occurrence, Distribution, and Extraction Methods in Marine Organisms
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作者 Boluwatife S. Olubusoye Peter Oni +6 位作者 Faustina Owusu Oluwatoyin Adekoya Acaye Ongwech Daniel A. Odogwu Oluwafemi Awolesi Ayobami Oje Beatrice Arwenyo 《Open Journal of Ecology》 2023年第12期931-955,共25页
The pervasive presence of microplastics in marine environments has raised significant concerns. This review addresses the pressing issue of microplastic pollution in marine ecosystems and its potential implications fo... The pervasive presence of microplastics in marine environments has raised significant concerns. This review addresses the pressing issue of microplastic pollution in marine ecosystems and its potential implications for both the environment and human health. It outlines the current state of microplastic occurrence, distribution, and extraction methods within marine organisms. Microplastics have emerged as a significant environmental concern due to their harmful effects on ecosystems and their potential human health risks. These particles infiltrate marine environments through runoff and atmospheric deposition, ultimately contaminating beaches and posing threats to marine life. Despite the gravity of this issue, there has been limited research on the presence and distribution of microplastics in marine organisms. This review aims to bridge this knowledge gap by comprehensively examining the occurrence, distribution, and various extraction methods used to detect microplastics in marine organisms. It emphasizes the urgent need for targeted measures to manage microplastic pollution, highlights the significant role of human activities in contributing to this problem, and underscores the importance of reducing human-induced pollution to safeguard marine ecosystems. While this paper contributes to the understanding of microplastic pollution in marine environments and underscores the critical importance of taking action to protect marine organisms and preserve our oceans for future generations, it also emphasizes that, in effectively tackling the microplastic problem, a well-coordinated approach is essential, involving research initiatives, policy adjustments, public involvement, and innovative technologies. Crucially, prompt and resolute responses must exist to counteract the escalating peril posed by microplastics to the oceans and the global environment. 展开更多
关键词 Microplastics Marine Environment Marine Organisms extraction methods Ecological Impact Ocean Pollution
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Arc Extraction Analysis for Circularity Measurement of Small Cylindrical Parts by the Segmenting-stitching Method
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作者 ZHAO Jiali WU Dan +2 位作者 ZHANG Liang SHEN Bobo LI Qiaolin 《Instrumentation》 2023年第3期1-11,共11页
To reduce the stitching error of circularity measurement of small cylindrical workpieces(Diameter less than 3 mm)by the segmenting-stitching method,arc contour extraction is analyzed in this paper.The coordinates of c... To reduce the stitching error of circularity measurement of small cylindrical workpieces(Diameter less than 3 mm)by the segmenting-stitching method,arc contour extraction is analyzed in this paper.The coordinates of cross-sectional circle of a small cylindrical part are segmented into several equal arcs to be obtained by a two-dimensional coordinate measuring machine.The circularity contour of the small cylindrical part can be formed by stitching a series of arc contours which are calculated by the obtained arc coordinate data.Due to the different measuring pressure angles of different measuring positions,the accuracy of obtained arc coordinate points is different.The bigger the pressure angle is,the accurate the obtained arc coordinate data are.The experiments show that the accuracy of two ends of the arc data is not as good as the central part.Therefore,the two ends of the obtained arc data are appropriately to be cut off,namely,only the central part of the arc data are extracted to be used for the stitching.As a result,the mean value of the matching coefficient is enhanced by 12%,the deviation between the overlap part of the neighbouring arc contour is reduced by 26%,and the average curvature of the arc contours is improved with the extraction method.Thus,the accuracy of the stitched circularity contour can be improved by this extraction procedure in the segmenting-stitching method for the circularity measurement of the small cylindrical parts. 展开更多
关键词 Circularity Measurement Arc extraction Small Cylindrical Workpiece Segmenting-stitching method
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Use of packed-fiber solid-phase extraction for sample clean-up and preconcentration of vitamin B_(12) before determination 被引量:5
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作者 Fang Fang Xue Jun Kang Zhi Yong Liu Yu Qin Ma Zhong Ze GU 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1491-1494,共4页
A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitami... A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection (LOD) is 5 ng mL^-1 (S/N = 3). Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink. 展开更多
关键词 Vitamin B12 NANOFIBERS Packed-fiber solid-phase extraction PRECONCENTRATION
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Fast determination of multi-mycotoxins in corn by dispersive solid-phase extraction coupled with ultra-performance liquid chromatography with tandem quadrupole time-of-flight mass spectrometry 被引量:3
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作者 WANG Yan DONG Yan-jie +5 位作者 LI Zeng-mei DENG Li-gang GUO Chang-ying ZHANG Shu-qiu LI Da-peng ZHAO Shan-cang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1656-1666,共11页
A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins (B1, B2, G1, and G2), fumonisins (B1, B2 and B3), zearalenone, and deoxynivalenol in corn using dispersive solid-ph... A fast analytical method for the simultaneous determination of 9 mycotoxins, including alfatoxins (B1, B2, G1, and G2), fumonisins (B1, B2 and B3), zearalenone, and deoxynivalenol in corn using dispersive solid-phase extraction method and ultra-performance liquid chromatography coupled to tandem quadrupole time-of-lfight mass spectrometry (UPLC-Q-TOF-MS) was developed and validated. Samples were extracted with acetonitrile-water (84:16, v:v, containing 1% acetic acid) using ultrasonic extraction. The extracts were puriifed with a dispersive SPE method using C18 as a cleaning agent. The ifnal clear extracts were dried by nitrogen blowing and subsequently redissolved in methanol-water (5:5, v:v). The samples were then analyzed by UPLC-Q-TOF-MS with 0.1% formic acid in ammonium acetate-methanol as mobile phase. The mean recoveries were ranged from 68.0 to 120.0%, and the relative standard deviation (RSD) ranged from 0.18 to 6.29%. Limits of detections ranged from 0.05 to 50 μg kg?1, and limits of quantiifcation ranged from 0.1 to 200 μg kg?1, which were below the legal limits set by the European Union for the legislated mycotoxins. The developed method was applied to 130 corn samples. Among the mycotoxins studied, alfatoxins B1 and fumonisins B1, B2 and B3 were the most predominant mycotoxins, and their concentrations were 0–593.12, 0–2.01×104, 0–6.94×103 and 0–3.05×103 μg kg–1, respectively. 展开更多
关键词 C18 CORN mycotoxins dispersive solid-phase extraction
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Trace determination and characterization of ginsenosides in rat plasma through magnetic dispersive solid-phase extraction based on core-shell polydopamine-coated magnetic nanoparticles 被引量:2
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作者 Ningning Zhao Shu Liu +3 位作者 Junpeng Xing Zifeng Pi Fengrui Song Zhiqiang Liu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第1期86-95,共10页
Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multip... Enrichment of trace bioactive constituents and metabolites from complex biological samples is challenging.This study presented a one-pot synthesis of magnetic polydopamine nanoparticles(Fe3O4@-SiO2@PDA NPs)with multiple recognition sites for the magnetic dispersive solid-phase extraction(MDSPE)of ginsenosides from rat plasma treated with white ginseng.The extracted ginsenosides were characterized by combining an ultra-high-performance liquid chromatography coupled to a highresolution mass spectrometry with supplemental UNIFI libraries.Response surface methodology was statistically used to optimize the extraction procedure of the ginsenosides.The reusability of Fe3O4@-SiO2@PDA NPs was also examined and the results showed that the recovery rate exceeded 80%after recycling 6 times.Furthermore,the proposed method showed greater enrichment efficiency and could rapidly determine and characterize 23 ginsenoside prototypes and metabolites from plasma.In comparison,conventional methanol method can only detect 8 ginsenosides from the same plasma samples.The proposed approach can provide methodological reference for the trace determination and characterization of different bioactive ingredients and metabolites of traditional Chinese medicines and food. 展开更多
关键词 Fe3O4@SiO2@PDA NPs Multiple recognition sites Magnetic dispersive solid-phase extraction ENRICHMENT GINSENOSIDES
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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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Separation and Enrichment of Melamine in Feed by a New Molecularly Imprinted Solid-phase Extraction Column 被引量:1
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作者 Huang Huabin Zhuang Zhixia +2 位作者 Zhou Yanli Zhao Li Wang Xiaoru 《Animal Husbandry and Feed Science》 CAS 2014年第1期10-13,共4页
[ Objective] The research aimed to develop a new molecular imprinting solid-phase extraction column for the separation and enrichment of melamine in feed. [ Method] The molecular imprinting polymer of melamine was pre... [ Objective] The research aimed to develop a new molecular imprinting solid-phase extraction column for the separation and enrichment of melamine in feed. [ Method] The molecular imprinting polymer of melamine was prepared by mass polymerization method. This polymer was used as filler to prepare molecular imprinting polymer solid-phase extraction(MIP-SPE) column of melamine. The solid-phase extraction conditions were optimized and melamine content in concentrated solution was determined by using HPLC. [ Result] Melamine eould be separated selectively from feed and enriehed by self-made MIP-SPE column. It could wipe off complex matrix from feed and the addition recovery rate was 95%. The contrast experiment between MIP-SPE column and NMIP-SPE ( non-imprinted polymer- solid phase extraction) column showed that the extraction efficiency of the former was obviously higher than the latter. [ Conclusion] The home-made MIP- SPE column could be used to separate and enrich melamine in feed efficiently, with a broad application prospect. 展开更多
关键词 Molecular imprinting solid-phase extraction FEED MELAMINE
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Matrix Solid-phase Dispersion Extraction of Alkaloids from the Roots of Aconitum kusnezoffii Reichb 被引量:2
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作者 WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期23-27,共5页
Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots ofAconitum kusnezoffii Reichb. The determina... Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots ofAconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid support material, type of the elution solvent and the volume of the elution solvent were tested. Mean recoveries ranged from 93.16% to 102.73%, with relative standard deviations from 0.27% to 4.17%. With the extraction efficiency and time expenditure taken into account, MSPD extraction should be a comparatively good method. 展开更多
关键词 Matrix solid-phase dispersion Aconitine-type alkaloid Aconitum kusnezoffii Reichb. extraction High-performance liquid chromatography 1005-9040(2011 )-01-023-05
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Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction 被引量:1
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作者 LI Cun-man XIAO Yuan-sheng +3 位作者 XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期392-396,共5页
An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matog... An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products. 展开更多
关键词 Unstable compound Isolation and purification Preparative high performance liquid chromatography solid-phase extraction Iridoid glucoside
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Determination of Trace Amount of Polycyclic Aromatic Hydrocarbons in Urban Sewage by Solid-phase Extraction Coupled with High Performance Liquid Chromatograph 被引量:2
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作者 WANG Jing-fei1,KANG Quan-ying1,RONG Nan1,2,WU Yi-hong1,LI Hong-bo1 1.Hebei Provincial Academy of Environmental Science,Hebei Provincial Laboratory of Water Environmental Science,Shijiazhuang 050037,China 2.College of Chemistry and Environmental Science,Hebei University,Baoding 071002,China 《Meteorological and Environmental Research》 CAS 2011年第10期91-94,共4页
[Method] This study aimed to determine trace amount of polycyclic aromatic hydrocarbons(PAHs) in urban sewage by using solid-phase extraction(SPE) coupled with high performance liquid chromatograph(HPLC).[Method] From... [Method] This study aimed to determine trace amount of polycyclic aromatic hydrocarbons(PAHs) in urban sewage by using solid-phase extraction(SPE) coupled with high performance liquid chromatograph(HPLC).[Method] From the aspects of solid-phase extraction column,elution solvent,elution volume,elution speed and so forth,the test conditions of SPE-HPLC method were optimized,and trace amount of PAHs in urban sewage was determined.[Result] The optimized solid-phase extraction conditions were SUPELCLEAN LC-18 solid-phase extraction column,methylene dichloride as elution solvent,15 ml elution volume,2 ml/min elution speed,5 ml/min loading speed,1 000 ml water with 200 ml methanol loading volume.Under the optimized extraction conditions,the recovery was high,namely 76.3%-105.2%;relative standard deviation was 3.8%-6.0%,showing good precision;detection limit was low,only 0.000 8-0.048 0 μg/L.[Conclusion] This method is user-friendly,with high sensitivity and good precision,and suitable for continuous determination of a large volume of water samples. 展开更多
关键词 solid-phase extraction(SPE) High performance liquid chromatograph(HPLC) Polycyclic aromatic hydrocarbons(PAHs) Urban sewage China
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