[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
A simple and sensitive analytical procedure for the determination of multi-component compounds in water samples was developed and optimized using the headspace solid-phase microextraction(HSSPME) coupled with gas chro...A simple and sensitive analytical procedure for the determination of multi-component compounds in water samples was developed and optimized using the headspace solid-phase microextraction(HSSPME) coupled with gas chromatography-mass spectrometry(GC-MS). Ten off-flavor compounds, including geosmin(GSM), 2-methylisoborneol(2-MIB), 2-isopropyl-3-methoxypyrazine(IPMP), 2-isobutyl-3-methoxypyrazine(IBMP), β-ionone, trans-2,cis-6-nonadienal(NDE), 2,3,4-trichloroanisole(2,3,4-TCA), 2,3,6-trichroloanisole(2,3,6-TCA), 2,4,6-trichloroanisole(2,4,6-TCA), and 2,4,6-tribromoanisole(2,4,6-TBA) were used as the target analytes. The optimization of extraction parameters including fibers types, extraction time, extraction temperature, stirring rate, sample volume, and ionic strength was carried out through the univariate approach. Ten off-flavor compounds were quantified within 50 min under the optimal conditions. Calibration curves with good linearity(r^2=0.990-0.998) were obtained in the range 1.0/2.0-100 ng/L, while the limits of detection for all compounds were lower than or close to the odor threshold concentration. Furthermore, the proposed method was applied to analyzing and determining the off-flavor compounds in real water samples from water-treatment plants.展开更多
Volatile components of Fuzhou Yulu, a Chinese fish sauce, were analyzed by gas chromatography-mass spectrometry (GC-MS), and two pretreatment methods, i.e., purge and trap (P&T) GC-MS and ethyl acetate extraction...Volatile components of Fuzhou Yulu, a Chinese fish sauce, were analyzed by gas chromatography-mass spectrometry (GC-MS), and two pretreatment methods, i.e., purge and trap (P&T) GC-MS and ethyl acetate extraction followed by GC-MS, were compared. P&T-GC-MS method determined 12 components, including sulfur-containing constituents (such as dimethyl disulfide), nitrogen-containing constituents (such as pyrazine derivatives), aldehydes and ketones. Ethyl acetate extraction fol- lowed by GC-MS method detected 10 components, which were mainly volatile organic acids (such as benzenepropanoic acid) and esters. Neither of the two methods detected alcohols or trimethylamine. This study offers an important reference to determine volatile flavor components of traditional fish sauce through modem analysis methods.展开更多
The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas ...The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas chroma- tography-mass spectrometry (GC-MS) detection. The pesticides were extracted with ultrasonic device and 5.0 mL mixture of ethyl acetate and cyclohexane (1:1, v/v). Coextractants from sample matrices which may have interfere to the qualitative and quantitative analysis, such as pigments, were removed using GPC purification. Simultaneous full scan and selective ion monitor (scan/SIM) mode for GC-MS was used for qualitative and quantitative analysis, which pro- vided retention time and characteristic fragments ratio for each pesticide so as to positively identify each analyte. Rela- tive standard deviations (RSDs) were within 7.7% (5.0 - 22.5 μg/kg, n = 3). The recoveries of pesticide standards at the spiked concentration of 5.0 - 22.5 μg/kg were between 87.1% and 110.9%. Limits of detection (LODs) for the analytes were 0.16 - 3.2 μg/kg, which could meet the demand of routine analysis and TCM quality control.展开更多
An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid...An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid-liquid extraction, subtracting background of the lineal aliphatic hydrocarbon interferences and integration of chromatographic peaks containing selected ion PCBs masses (256, 292 and 326 m/z), which are common in all PCBs formulations. Recoveries were in the 80% - 120% range;PCBs were detected and quantified in shredder samples from an automotive shredder industry, thus indicating the validity of the method.展开更多
In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ...In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ingredients and rate of product were change greatly,The major chemical constituents were trans-anethole,estragole and anisaldehyde etc.展开更多
采用气相色谱-氢火焰离子化检测器法(gas chromatography with hydrogen flame ionization detection,GCFID)、顶空固相微萃取-气相色谱-质谱(headspace solid-phase microextraction coupled with gas chromatography-mass spectrometr...采用气相色谱-氢火焰离子化检测器法(gas chromatography with hydrogen flame ionization detection,GCFID)、顶空固相微萃取-气相色谱-质谱(headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry,HS-SPME-GC-MS)和电子鼻技术分析6种果酒中的挥发性成分,评价果酒风味轮廓特征的差异性。结果表明,GC-FID定量测定樱桃李酒,其中异戊醇、活性戊醇、β-苯乙醇含量最高,乙酸乙酯含量最低;木瓜酒中正丙醇、2,3-丁二醇、癸酸乙酯、乙酸含量最高; 3-羟基-2-丁酮含量在樱桃李酒中最高,山楂酒、甜橙酒中最少。HP-SPME-GC-MS鉴定果酒中挥发性物质94种,其中醇类23种,酯类43种,醛酮类10种,酸类8种,酚类2种,苯环类5种,烷烃类3种。山楂酒、菠萝酒、木瓜酒、甜橙酒、无花果酒和樱桃李酒中香气物质数量分别为34、44、45、45、33、47种。其中山楂酒、木瓜酒和无花果酒中未检出酚类、烷烃类物质。电子鼻对不同果酒香气的区分效果无重叠,W5S传感器区分果酒香气能力最强。比较而言,菠萝酒和樱桃李酒的口感更圆润,香气更愉悦,感官得分最高。展开更多
[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extr...[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry (GC/MS). [Result] The results show that cedrol (46.39%) is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate (59.46%) is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value.展开更多
Active volatile components in drug pair(DP)Herba Ephedrae-Ramulus Cinnamomi(HE-RC),single drug HE and RC were analyzed by gas chromatography/mass spectrometry(GC/MS),chemometric resolution method(CRM)and overall volum...Active volatile components in drug pair(DP)Herba Ephedrae-Ramulus Cinnamomi(HE-RC),single drug HE and RC were analyzed by gas chromatography/mass spectrometry(GC/MS),chemometric resolution method(CRM)and overall volume integration.By means of CRM,the two-dimensional data obtained from GC-MS instruments were resolved into a pure chromatogram and a mass spectrum of each chemical compound.In total,97,62,and 78 volatile chemical components in volatile oil of HE,RC,and DP HE-RC,were respectively determined qualitatively and quantitatively,accounting for 90.08%,91.62%,and 89.76% total contents of volatile oil of HE,RC,and DP HE-RC respectively.It is further demonstrated that the numbers of volatile components of DP HE-RC are almost the sum of those of two single drugs,but some relative contents of them are changed.Some new components,such as 1,6-dimethylhepta-1,3,5-triene,tetracyclo[4.2.1.1(2,5).0(9,10)]deca-3,7-diene,globulol and(E,E)-6,10,14-trimethyl-5,9,13-pentadecatrien-2-one are found in DP HE-RC because of chemical reactions and physical changes during decoction.展开更多
[Objectives] To determine the aromatic components of Rosa davurica Pall. [Methods] 42 kinds of aromatic components were identified from the flowers of R. davurica by headspace solid phase microextraction( HS-SPME) com...[Objectives] To determine the aromatic components of Rosa davurica Pall. [Methods] 42 kinds of aromatic components were identified from the flowers of R. davurica by headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS). The main compounds were alcohols( 54. 88%) and aldehydes( 19. 55%). [Results] The top five components with the highest relative content were phenylethyl alcohol( 12. 69%),geraniol( 9. 85%),citronellol( 8. 80%),nerol( 7. 84%) and 2-n-pentylfuran( 7. 45%). [Conclusions] Headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS) can provide basis for further development and utilization of R. davurica.展开更多
The essential oil of Zanthoxylum armatum was extracted through hydro distillation and analyzed by GC-MS. Hydrocarbon fraction (17.35%) of the oil was much lower and oxygenated compounds comprised fairly high portion o...The essential oil of Zanthoxylum armatum was extracted through hydro distillation and analyzed by GC-MS. Hydrocarbon fraction (17.35%) of the oil was much lower and oxygenated compounds comprised fairly high portion of essential oil (39.21%). Percentages of monoterpenes and sesquiterpenes found were 47.33% and 10.83% respectively. Oxygenated monoterpenes comprised major profile of chromatogram of essential oil of Zanthoxylum armatum i.e. 37.23% where as monoterpene hydrocarbons were 10.09%. Alcoholic percentage was much higher i.e. 26.76% and 15-hexadecanoloide (6.58%) the only cyclic ester was found in relatively high percentage.展开更多
Gas chromatography mass spectrometry (GC-MS) is a widely used central analytical technology. Commercially available GC-MS systems use different types of mass analyzers such as Quadrupole, Ion Trap and/or Time of Fligh...Gas chromatography mass spectrometry (GC-MS) is a widely used central analytical technology. Commercially available GC-MS systems use different types of mass analyzers such as Quadrupole, Ion Trap and/or Time of Flight, but practically all systems utilize the same Nier type electron ionization (EI) ion source and the same standard GC-MS transferline interface. Consequently, the various GC-MS vendors characterize their systems by a short list of specifications that relate to improvements in the technology of GC or of MS and not of the interfacing technology and ion source. This article presents a list of 62 ways in which the performance of GC-MS as a whole can be improved by an innovative interface and ion source. Such an interface can possibly lead to a GC-MS revolution in a way that is similar to that whichis brought to Liquid Chromatography Mass Spectrometry (LC-MS) by the Electrospray ionization interface and ion source and not by improvements to the technology of LC or MS. These 62 possible GC-MS improvements (grouped into eight main categories) are not merely theoretical as they are provided by the Cold-EI GC-MS interface, which is based on the ionization of vibrationally cold sample molecules in a Supersonic Molecular Beam (SMB) within a fly-through ion source. An explanation and discussion is provided for each of these possible improvements.展开更多
Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively...Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.展开更多
(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-...(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-sesamin and CC-MS for its identification. The result suggested that this approach could be used to identify Semen Cuscutae from various sources based on the different content of(+)-sesamin in them.展开更多
基金Supported by The Fourth Batch of High-end Talent Project in Hebei Province.
文摘[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.
基金Project(21277175) supported by the National Natural Science Foundation of ChinaProject(JCYJ20120618164317119) supported by Shenzhen Special Fund for Development of Strategic Emerging,China
文摘A simple and sensitive analytical procedure for the determination of multi-component compounds in water samples was developed and optimized using the headspace solid-phase microextraction(HSSPME) coupled with gas chromatography-mass spectrometry(GC-MS). Ten off-flavor compounds, including geosmin(GSM), 2-methylisoborneol(2-MIB), 2-isopropyl-3-methoxypyrazine(IPMP), 2-isobutyl-3-methoxypyrazine(IBMP), β-ionone, trans-2,cis-6-nonadienal(NDE), 2,3,4-trichloroanisole(2,3,4-TCA), 2,3,6-trichroloanisole(2,3,6-TCA), 2,4,6-trichloroanisole(2,4,6-TCA), and 2,4,6-tribromoanisole(2,4,6-TBA) were used as the target analytes. The optimization of extraction parameters including fibers types, extraction time, extraction temperature, stirring rate, sample volume, and ionic strength was carried out through the univariate approach. Ten off-flavor compounds were quantified within 50 min under the optimal conditions. Calibration curves with good linearity(r^2=0.990-0.998) were obtained in the range 1.0/2.0-100 ng/L, while the limits of detection for all compounds were lower than or close to the odor threshold concentration. Furthermore, the proposed method was applied to analyzing and determining the off-flavor compounds in real water samples from water-treatment plants.
基金supported by the Science and Technology Bureau of FujianProvince, China (No. B50701)the Foundation for Young Pro-fessors of Jimei University, China (No. C19005)
文摘Volatile components of Fuzhou Yulu, a Chinese fish sauce, were analyzed by gas chromatography-mass spectrometry (GC-MS), and two pretreatment methods, i.e., purge and trap (P&T) GC-MS and ethyl acetate extraction followed by GC-MS, were compared. P&T-GC-MS method determined 12 components, including sulfur-containing constituents (such as dimethyl disulfide), nitrogen-containing constituents (such as pyrazine derivatives), aldehydes and ketones. Ethyl acetate extraction fol- lowed by GC-MS method detected 10 components, which were mainly volatile organic acids (such as benzenepropanoic acid) and esters. Neither of the two methods detected alcohols or trimethylamine. This study offers an important reference to determine volatile flavor components of traditional fish sauce through modem analysis methods.
文摘The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas chroma- tography-mass spectrometry (GC-MS) detection. The pesticides were extracted with ultrasonic device and 5.0 mL mixture of ethyl acetate and cyclohexane (1:1, v/v). Coextractants from sample matrices which may have interfere to the qualitative and quantitative analysis, such as pigments, were removed using GPC purification. Simultaneous full scan and selective ion monitor (scan/SIM) mode for GC-MS was used for qualitative and quantitative analysis, which pro- vided retention time and characteristic fragments ratio for each pesticide so as to positively identify each analyte. Rela- tive standard deviations (RSDs) were within 7.7% (5.0 - 22.5 μg/kg, n = 3). The recoveries of pesticide standards at the spiked concentration of 5.0 - 22.5 μg/kg were between 87.1% and 110.9%. Limits of detection (LODs) for the analytes were 0.16 - 3.2 μg/kg, which could meet the demand of routine analysis and TCM quality control.
文摘An easy and rapid method is proposed for the determination of PCBs in automotive shredder residues, using gas chromatography combined with low resolution mass spectrometry (GC-MS). It is based on direct n-hexane solid-liquid extraction, subtracting background of the lineal aliphatic hydrocarbon interferences and integration of chromatographic peaks containing selected ion PCBs masses (256, 292 and 326 m/z), which are common in all PCBs formulations. Recoveries were in the 80% - 120% range;PCBs were detected and quantified in shredder samples from an automotive shredder industry, thus indicating the validity of the method.
文摘In this paper,the Illilium verum Hook.f.grow at mountain of Dayao of Jinxiu in Guangxi,Volatile oil was extracted by soxhet method and steam distillation.All the volatile oil was analyzed by GC-MS,the result show the ingredients and rate of product were change greatly,The major chemical constituents were trans-anethole,estragole and anisaldehyde etc.
文摘采用气相色谱-氢火焰离子化检测器法(gas chromatography with hydrogen flame ionization detection,GCFID)、顶空固相微萃取-气相色谱-质谱(headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry,HS-SPME-GC-MS)和电子鼻技术分析6种果酒中的挥发性成分,评价果酒风味轮廓特征的差异性。结果表明,GC-FID定量测定樱桃李酒,其中异戊醇、活性戊醇、β-苯乙醇含量最高,乙酸乙酯含量最低;木瓜酒中正丙醇、2,3-丁二醇、癸酸乙酯、乙酸含量最高; 3-羟基-2-丁酮含量在樱桃李酒中最高,山楂酒、甜橙酒中最少。HP-SPME-GC-MS鉴定果酒中挥发性物质94种,其中醇类23种,酯类43种,醛酮类10种,酸类8种,酚类2种,苯环类5种,烷烃类3种。山楂酒、菠萝酒、木瓜酒、甜橙酒、无花果酒和樱桃李酒中香气物质数量分别为34、44、45、45、33、47种。其中山楂酒、木瓜酒和无花果酒中未检出酚类、烷烃类物质。电子鼻对不同果酒香气的区分效果无重叠,W5S传感器区分果酒香气能力最强。比较而言,菠萝酒和樱桃李酒的口感更圆润,香气更愉悦,感官得分最高。
基金Supported by Sub-project of the "Eleventh Five-Year" National Science and Technology Support Program (2006BAD19B04)~~
文摘[Objective] This study aimed to analyze the chemical composition and yield of essential oil and n-hexane extract from moso bamboo to find active compounds with potential value. [Method] Essential oil and n-hexane extract were respectively extracted from moso bamboo of four different ages by using hydrodistillation and ultrasonic-assisted extraction with n-hexane, and analyzed with gas chromatography/mass spectrometry (GC/MS). [Result] The results show that cedrol (46.39%) is the first principal volatile component in essential oil of the middle stem of 7-year old moso bamboo; dibutyl phthalate (59.46%) is the first principal volatile component in n-hexane extract of the middle stem of 3-year old moso bamboo; yield of n-hexane extract is higher than that of essential oil from moso bamboo. [Conclusion] Cedrol is an active compound with potential value.
基金Project (01962502) supported by the Natural Science Foundation of Hunan Province, China
文摘Active volatile components in drug pair(DP)Herba Ephedrae-Ramulus Cinnamomi(HE-RC),single drug HE and RC were analyzed by gas chromatography/mass spectrometry(GC/MS),chemometric resolution method(CRM)and overall volume integration.By means of CRM,the two-dimensional data obtained from GC-MS instruments were resolved into a pure chromatogram and a mass spectrum of each chemical compound.In total,97,62,and 78 volatile chemical components in volatile oil of HE,RC,and DP HE-RC,were respectively determined qualitatively and quantitatively,accounting for 90.08%,91.62%,and 89.76% total contents of volatile oil of HE,RC,and DP HE-RC respectively.It is further demonstrated that the numbers of volatile components of DP HE-RC are almost the sum of those of two single drugs,but some relative contents of them are changed.Some new components,such as 1,6-dimethylhepta-1,3,5-triene,tetracyclo[4.2.1.1(2,5).0(9,10)]deca-3,7-diene,globulol and(E,E)-6,10,14-trimethyl-5,9,13-pentadecatrien-2-one are found in DP HE-RC because of chemical reactions and physical changes during decoction.
基金Supported by Key Science and Technology Project of Gansu Province(1302NKDA028)Science and Technology Planning Project of Lanzhou(2010-1-239+2 种基金 2016-3-4)Talent Project of Lanzhou Science and Technology Bureau(2015-RC-87)Project of Science and Technology Cooperation between Gansu Academy of Agricultural Sciences and Local Areas(2017GAAS63)
文摘[Objectives] To determine the aromatic components of Rosa davurica Pall. [Methods] 42 kinds of aromatic components were identified from the flowers of R. davurica by headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS). The main compounds were alcohols( 54. 88%) and aldehydes( 19. 55%). [Results] The top five components with the highest relative content were phenylethyl alcohol( 12. 69%),geraniol( 9. 85%),citronellol( 8. 80%),nerol( 7. 84%) and 2-n-pentylfuran( 7. 45%). [Conclusions] Headspace solid phase microextraction( HS-SPME) combined with gas chromatography-mass spectrometry( GC-MS) can provide basis for further development and utilization of R. davurica.
文摘The essential oil of Zanthoxylum armatum was extracted through hydro distillation and analyzed by GC-MS. Hydrocarbon fraction (17.35%) of the oil was much lower and oxygenated compounds comprised fairly high portion of essential oil (39.21%). Percentages of monoterpenes and sesquiterpenes found were 47.33% and 10.83% respectively. Oxygenated monoterpenes comprised major profile of chromatogram of essential oil of Zanthoxylum armatum i.e. 37.23% where as monoterpene hydrocarbons were 10.09%. Alcoholic percentage was much higher i.e. 26.76% and 15-hexadecanoloide (6.58%) the only cyclic ester was found in relatively high percentage.
文摘Gas chromatography mass spectrometry (GC-MS) is a widely used central analytical technology. Commercially available GC-MS systems use different types of mass analyzers such as Quadrupole, Ion Trap and/or Time of Flight, but practically all systems utilize the same Nier type electron ionization (EI) ion source and the same standard GC-MS transferline interface. Consequently, the various GC-MS vendors characterize their systems by a short list of specifications that relate to improvements in the technology of GC or of MS and not of the interfacing technology and ion source. This article presents a list of 62 ways in which the performance of GC-MS as a whole can be improved by an innovative interface and ion source. Such an interface can possibly lead to a GC-MS revolution in a way that is similar to that whichis brought to Liquid Chromatography Mass Spectrometry (LC-MS) by the Electrospray ionization interface and ion source and not by improvements to the technology of LC or MS. These 62 possible GC-MS improvements (grouped into eight main categories) are not merely theoretical as they are provided by the Cold-EI GC-MS interface, which is based on the ionization of vibrationally cold sample molecules in a Supersonic Molecular Beam (SMB) within a fly-through ion source. An explanation and discussion is provided for each of these possible improvements.
文摘Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.
基金NSFC, Grant !No. 29875001National ninth five-year Sci. & Tech. program of China, Grant !No. 96-903-02-02.
文摘(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-sesamin and CC-MS for its identification. The result suggested that this approach could be used to identify Semen Cuscutae from various sources based on the different content of(+)-sesamin in them.