The present study employed an imaging mass spectrometry (IMS) method to evaluate the effect of dietary n – 3 fatty acids on the fatty acid composition in rat brain. Rats were divided into two groups and fed either an...The present study employed an imaging mass spectrometry (IMS) method to evaluate the effect of dietary n – 3 fatty acids on the fatty acid composition in rat brain. Rats were divided into two groups and fed either an n – 3 fatty acid-deficient or adequate diet. We determined the decreased n – 3 fatty acids in the hippocampus of rats fed an n – 3 fatty acid-deficient diet compared to the control. IMS visualization was achieved at a resolution of 100 m in rat brain, and showed decreased docosahexaenoic acid (DHA)-containing phosphatidyl choline (PC) or phosphatidyl ethanolamine (PE) in the hippocampus of rats fed an n – 3 fatty acid-deficient diet.展开更多
Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN...Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.展开更多
FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most freque...FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most frequently used proteomics approach,a single LC-MS run can reveal tens and even hundreds of useful information.For each peptide selected for MS/MS,two data-files were generated,one for ECD and another one for CAD.They were merged as described and submitted to the Mascot search engine using the protein database.These thresholds ensure almost 100% statistical confident in the peptide identification.展开更多
检测微生物采油(MEOR)过程采出液中的有机物组成特征是研究微生物采油机理的重要方法。针对MEOR采出液中有机物组成复杂,生物表面活性剂组成分析困难的特点,采用傅里叶变换离子回旋共振质谱仪(FT-ICR-MS)对新疆六中区微生物驱油过程中3...检测微生物采油(MEOR)过程采出液中的有机物组成特征是研究微生物采油机理的重要方法。针对MEOR采出液中有机物组成复杂,生物表面活性剂组成分析困难的特点,采用傅里叶变换离子回旋共振质谱仪(FT-ICR-MS)对新疆六中区微生物驱油过程中3口采油井不同时期采出液中的含氧极性化合物组成进行研究。检测到样品中含氧极性化合物含量最高的为O2、O3、O4、O7、O9类化合物,在微生物驱替过程中,样品中的O7和O9类化合物含量升高,检测到的鼠李糖脂有C 16 H 30 O 7、C 18 H 34 O 7、C 14 H 26 O 7、C 18 H 30 O 7、C 14 H 26 O 7、C 24 H 44 O 9,主要为O7和O9类的单鼠李糖脂。结果表明研究区块微生物驱油过程中激活的内源微生物能够在地层环境中代谢产生鼠李糖脂,随着微生物驱油的进行,鼠李糖脂的种类变多。展开更多
In the present work,a comparative study of analytical methods for the simultaneous and quantitative determination of trivalent and hexavalent chromium is presented.For the analysis by ion chromatography-inductively co...In the present work,a comparative study of analytical methods for the simultaneous and quantitative determination of trivalent and hexavalent chromium is presented.For the analysis by ion chromatography-inductively coupled plasma-mass spectrometry,two different columns were tested,as well as different mobile phases and different pH of the samples.The optimized analytical method permitted the separation of Cr(Ⅲ)and Cr(Ⅵ)using 75 mmol/L NH_(4)NO_(3)pH 3 as chromatographic eluent.The method was validated and applied to real samples,allowing the determination of both species simultaneously,even when there is a huge difference of concentration between Cr(Ⅲ)and Cr(Ⅵ).Limit of detection and limit of quantification for Cr(Ⅲ)were found to be 0.016 and 0.054μg/L(0.3 and 1.1μg/kg),respectively,and for Cr(Ⅵ)0.13 and 0.43μg/L(7 and 22μg/kg),respectively.Possible species interconversions were monitored through the use of chromium isotopic standards,which confirmed that the optimized methodology preserves chromium speciation during extraction and analysis.Fourier-transform ion cyclotron resonance-mass spectrometry permitted the structure elucidation of the complex formed during ethylenediaminetetraacetic acid extraction.展开更多
文摘The present study employed an imaging mass spectrometry (IMS) method to evaluate the effect of dietary n – 3 fatty acids on the fatty acid composition in rat brain. Rats were divided into two groups and fed either an n – 3 fatty acid-deficient or adequate diet. We determined the decreased n – 3 fatty acids in the hippocampus of rats fed an n – 3 fatty acid-deficient diet compared to the control. IMS visualization was achieved at a resolution of 100 m in rat brain, and showed decreased docosahexaenoic acid (DHA)-containing phosphatidyl choline (PC) or phosphatidyl ethanolamine (PE) in the hippocampus of rats fed an n – 3 fatty acid-deficient diet.
文摘Biological mass spectrometry has received a great progress in recent years.The osteopontin(OPN) isolated and purified from the human milk was studied by HPLC using SCX and C4 columns.After hydrolyzing the purified OPN sample by trypsin,the correlative polypeptide fragments GDSVVYGLR and QNLLAPQTLPSK were obtained by FT-ICR-MS.It showed that the method of nano-spray HPLC combined with FT-ICR-MS and Mascot search was very efficient for the analysis of the purified OPN and its polypeptide fragments.Further study provides more academic theories of their different modifications and the relative bioactivities.
文摘FT-ICR-MS technology has significant sensitivity and dynamic range,enabling the detection of different fragmentations of peptides and proteins at lower and lower levels.In the bottom-up approach,by far the most frequently used proteomics approach,a single LC-MS run can reveal tens and even hundreds of useful information.For each peptide selected for MS/MS,two data-files were generated,one for ECD and another one for CAD.They were merged as described and submitted to the Mascot search engine using the protein database.These thresholds ensure almost 100% statistical confident in the peptide identification.
文摘检测微生物采油(MEOR)过程采出液中的有机物组成特征是研究微生物采油机理的重要方法。针对MEOR采出液中有机物组成复杂,生物表面活性剂组成分析困难的特点,采用傅里叶变换离子回旋共振质谱仪(FT-ICR-MS)对新疆六中区微生物驱油过程中3口采油井不同时期采出液中的含氧极性化合物组成进行研究。检测到样品中含氧极性化合物含量最高的为O2、O3、O4、O7、O9类化合物,在微生物驱替过程中,样品中的O7和O9类化合物含量升高,检测到的鼠李糖脂有C 16 H 30 O 7、C 18 H 34 O 7、C 14 H 26 O 7、C 18 H 30 O 7、C 14 H 26 O 7、C 24 H 44 O 9,主要为O7和O9类的单鼠李糖脂。结果表明研究区块微生物驱油过程中激活的内源微生物能够在地层环境中代谢产生鼠李糖脂,随着微生物驱油的进行,鼠李糖脂的种类变多。
基金supported by University of Rouen Normandy,INSA Rouen Normandy,the Centre National de la Recherche Scientifque(CNRS),European Regional Development Fund(ERDF HN0001343)Labex Syn-Org(ANR-11-LABX-0029)+1 种基金Carnot Institute I2C,the graduate school for research XL-Chem(ANR-18-EURE-0020 XL CHEM)Region Normandie,and Consejo Nacional de Ciencia y Tecnologia(CONACYT CVU 707668).
文摘In the present work,a comparative study of analytical methods for the simultaneous and quantitative determination of trivalent and hexavalent chromium is presented.For the analysis by ion chromatography-inductively coupled plasma-mass spectrometry,two different columns were tested,as well as different mobile phases and different pH of the samples.The optimized analytical method permitted the separation of Cr(Ⅲ)and Cr(Ⅵ)using 75 mmol/L NH_(4)NO_(3)pH 3 as chromatographic eluent.The method was validated and applied to real samples,allowing the determination of both species simultaneously,even when there is a huge difference of concentration between Cr(Ⅲ)and Cr(Ⅵ).Limit of detection and limit of quantification for Cr(Ⅲ)were found to be 0.016 and 0.054μg/L(0.3 and 1.1μg/kg),respectively,and for Cr(Ⅵ)0.13 and 0.43μg/L(7 and 22μg/kg),respectively.Possible species interconversions were monitored through the use of chromium isotopic standards,which confirmed that the optimized methodology preserves chromium speciation during extraction and analysis.Fourier-transform ion cyclotron resonance-mass spectrometry permitted the structure elucidation of the complex formed during ethylenediaminetetraacetic acid extraction.
