The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide s...The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide scientific basis for the quality control of safflower. Five different solvents (diethyl ether, ethanol, ethyl acetate, dichloromethane and acetone) were used and compared in terms of number of volatile components extracted and the peak areas of these components in TIC. The results showed that USE could be used as an efficient and rapid method for extracting the volatile components from safflower. It also could be found that the number of components in the TIC of ethyl acetate extract was more than that in the TIC of other solvent ones. Meanwhile, the volatile components of safflower from Xinjiang Autonomous Region and Henan Province of China were different in chemical components and relative contents. It could be concluded that both the extraction solvents and geographical origin of safflower are responsible for these differences. The experimental results also indicated that USE/GC-MS is a simple, rapid and effective method to analyze the volatile oil components of safflower.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
An environmentally friendly method for extracting sulfonamides(SAs) residues from animal feed was described and applied. The method used online microwave-assisted steam extraction coupled with solid phase extraction...An environmentally friendly method for extracting sulfonamides(SAs) residues from animal feed was described and applied. The method used online microwave-assisted steam extraction coupled with solid phase extraction(MASE-SPE), which was followed by the analysis using high performance liquid chromatography-mass spectro- metry(HPLC-MS/MS). The SAs residues were extracted successively with water steam under microwave irradiation, and thus directly introduced into an SPE colunm containing cation-exchange resin. The SAs were then eluted with methanol-ammonia(90:10, volume ratio) from the SPE column and followed by HPLC-MS/IVIS. The limits of detec- tion(LODs) for the analytes ranged from 0.24 ng/g to 0.49 ng/g. The limits of quantification(LOQs) ranged from 0.82 ng/g to 1.63 ng/g. Average recoveries of SAs were 76.3%--92.1%. The developed method was a reliable and envi-ronmentally friendly alternative to previous methods with respect to time, solvent and labor consumption for the analysis of SAs in animal foodstuffs.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, a method using solid-phase extraction (SPE) and gas chromatography-mass spectro- metry (GC-MS) was developed to simultaneously analyze five taste and odor compounds in surface water, i.e., 2- methyl...In this paper, a method using solid-phase extraction (SPE) and gas chromatography-mass spectro- metry (GC-MS) was developed to simultaneously analyze five taste and odor compounds in surface water, i.e., 2- methylisoborneol (2-MIB), 2,4,6-trichloroanisole (TCA), 2-isopropyl-3-methoxy pyrazine (IPMP), 2-isobutyl-3- methoxy pyrazine (IBMP), and trans-l,lO-dimethyl- trans-9-decalol (geosmin, GSM). The mass spectrometry was operated in selective ion monitoring (SIM) mode. Three kinds of SPE columns and three eluting solvents were compared, the C 18 column was chosen as optimum SPE column, and methanol was chosen as the optimum eluting solvent. It was found that the method showed good linearity in the range of 1-200 ng.L^-1 and gave detection limits of 0.5 1.5 ng.L^-1 for individual compounds. Good recoveries (93.5%-108%) and relative standard deviations (1.58%-7.31%) were also obtained. Additionally, concentrations of these taste and odor compounds in Jinan's surface and drinking water were analyzed by applying this method, and the results showed that GSM and 2-MIB were the dominant taste and odor compounds in Jinan's raw water.展开更多
文摘The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide scientific basis for the quality control of safflower. Five different solvents (diethyl ether, ethanol, ethyl acetate, dichloromethane and acetone) were used and compared in terms of number of volatile components extracted and the peak areas of these components in TIC. The results showed that USE could be used as an efficient and rapid method for extracting the volatile components from safflower. It also could be found that the number of components in the TIC of ethyl acetate extract was more than that in the TIC of other solvent ones. Meanwhile, the volatile components of safflower from Xinjiang Autonomous Region and Henan Province of China were different in chemical components and relative contents. It could be concluded that both the extraction solvents and geographical origin of safflower are responsible for these differences. The experimental results also indicated that USE/GC-MS is a simple, rapid and effective method to analyze the volatile oil components of safflower.
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.
基金Supported by the National High Technology Research and Development Program of China(No.2011AA100805) and the National Natural Science Foundation of China(No.20875037).
文摘An environmentally friendly method for extracting sulfonamides(SAs) residues from animal feed was described and applied. The method used online microwave-assisted steam extraction coupled with solid phase extraction(MASE-SPE), which was followed by the analysis using high performance liquid chromatography-mass spectro- metry(HPLC-MS/MS). The SAs residues were extracted successively with water steam under microwave irradiation, and thus directly introduced into an SPE colunm containing cation-exchange resin. The SAs were then eluted with methanol-ammonia(90:10, volume ratio) from the SPE column and followed by HPLC-MS/IVIS. The limits of detec- tion(LODs) for the analytes ranged from 0.24 ng/g to 0.49 ng/g. The limits of quantification(LOQs) ranged from 0.82 ng/g to 1.63 ng/g. Average recoveries of SAs were 76.3%--92.1%. The developed method was a reliable and envi-ronmentally friendly alternative to previous methods with respect to time, solvent and labor consumption for the analysis of SAs in animal foodstuffs.
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, a method using solid-phase extraction (SPE) and gas chromatography-mass spectro- metry (GC-MS) was developed to simultaneously analyze five taste and odor compounds in surface water, i.e., 2- methylisoborneol (2-MIB), 2,4,6-trichloroanisole (TCA), 2-isopropyl-3-methoxy pyrazine (IPMP), 2-isobutyl-3- methoxy pyrazine (IBMP), and trans-l,lO-dimethyl- trans-9-decalol (geosmin, GSM). The mass spectrometry was operated in selective ion monitoring (SIM) mode. Three kinds of SPE columns and three eluting solvents were compared, the C 18 column was chosen as optimum SPE column, and methanol was chosen as the optimum eluting solvent. It was found that the method showed good linearity in the range of 1-200 ng.L^-1 and gave detection limits of 0.5 1.5 ng.L^-1 for individual compounds. Good recoveries (93.5%-108%) and relative standard deviations (1.58%-7.31%) were also obtained. Additionally, concentrations of these taste and odor compounds in Jinan's surface and drinking water were analyzed by applying this method, and the results showed that GSM and 2-MIB were the dominant taste and odor compounds in Jinan's raw water.