Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of...Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.展开更多
N,N-dialkylaminoethane-2-sulfonic acids are environmental marker compounds of V type nerve agents,hence analysis of them is very important for verification of the chemical weapons convention(CWC).In this article,liqui...N,N-dialkylaminoethane-2-sulfonic acids are environmental marker compounds of V type nerve agents,hence analysis of them is very important for verification of the chemical weapons convention(CWC).In this article,liquid chromatography-high resolution time of flight mass spectrometry coupled with accurate mass measurement were used to discriminate N,N-disopropyl aminoethane-2-sulfonic acid and a CWC non-related compound 3-(N-Morpholino)propanesulfonic acid in Water.The method was fast,simple and accurate,proving that high resolution mass spectrometry is a good technique for the analysis of unknown toxicant.展开更多
A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription termi...A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription terminator, was tandem repeatedly engineered into a expression plasmid. Consequently, the copy number of specific gene was increased substantially, leading to the improvement of expression efficiency.Using this approach, a recombinant plasmid , designed as PLYD, was constructed and transformated into the Escherichia coli strain DH5α. Upon induction , the desired protein was synthesized in a considerable level and accumulated up to 63% of the total cell proteins. The present study revealed that tandem repeating of expression cartridge provided a convenient means to improve expression level efficiently.展开更多
文摘Analysis of nerve agents and their degradation products constitutes an important subject for verifying the compliance to the Chemical Weapons Convention(CWC).In environmental water,the relevant degradation products of nerve agents are usually present at low concentration levels and mixed with a large amount of interferents.In this paper,six different kinds of solid-phase bulk sorbents were respectively investigated to improve the SPE efficiency for nerve agents degradation products from stimulant water samples,in which a large amount of background interferents were spiked.Results showed that the strong anion-exchange sorbent could selectively extract the spiking six target compounds from the matrices and showed a high recovery.
文摘N,N-dialkylaminoethane-2-sulfonic acids are environmental marker compounds of V type nerve agents,hence analysis of them is very important for verification of the chemical weapons convention(CWC).In this article,liquid chromatography-high resolution time of flight mass spectrometry coupled with accurate mass measurement were used to discriminate N,N-disopropyl aminoethane-2-sulfonic acid and a CWC non-related compound 3-(N-Morpholino)propanesulfonic acid in Water.The method was fast,simple and accurate,proving that high resolution mass spectrometry is a good technique for the analysis of unknown toxicant.
文摘A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription terminator, was tandem repeatedly engineered into a expression plasmid. Consequently, the copy number of specific gene was increased substantially, leading to the improvement of expression efficiency.Using this approach, a recombinant plasmid , designed as PLYD, was constructed and transformated into the Escherichia coli strain DH5α. Upon induction , the desired protein was synthesized in a considerable level and accumulated up to 63% of the total cell proteins. The present study revealed that tandem repeating of expression cartridge provided a convenient means to improve expression level efficiently.