N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are important markers of chemical warfare agents because they are structurally relative to both nerve agents and N-mustards. In this study, fragmentation pathways of the most characteristic fragment ions in Q-TOF mass spectrometry were proposed based on the information from accurate mass and secondary fragmentations of product ions scan experiments. Results indicated that the base ion in LC/HRMS was the quasi-molecular ion [M+H]+. In LC-HRMS/MS, it was [M+H-CnH2n+1P(O)(OH)CmH2m+1O]+ fragment ion which was formed by losing an alkyloxy alkylphosphoryloxy group from the quasi-molecular ion. The diagnostic ion m/z84.0814 was identified as [C5H10N]+, which was the group of (CH2=CH)2N+(H)CH3. PNPs have two protonated centers. One is on the N atom, the other is on the O atom (P=O). O-n-propyl PNPs generally exhibited two fragmentation pathways. Firstly, the quasi-molecular ion [M+H]+ lost a propoxy alkylphosphoryloxy group to produce [R1P(OH+)(O-n-C3H7)OCH2CH2N(CH3)CH=CH2]+, which could be fragmented further to produce [C5H10N]+ ion. Secondly, [R1P(OH+)(O-n-C3H7) OCH=CH2]+ ions were produced from [M+H]+ and fragmented further to produce the abundant ions [R1P(OH+)(OH)OCH =CH2]. However, O-isopropyl PNPs characteristically produced weak fragment ions [M+H-C3H6]+, which were presumably formed via loss of CH3CH=CH2 from [M+H]+. Other PNPs showed similar fragmentation pathways as O-n-propyl PNPs. On the summarization of the MS fragmentation pathways of PNPs, LC-HRMS/MS quantitative and qualitative methods were developed and applied to analyze N-Methyl bis(2-(butoxy-methylphosphoryloxy)ethyl]amine in high background organic samples. The analytical results had successfully supported the sample preparation for the 33rd official proficiency test of Organization for Prohibition of Chemical Weapons (OPCW).
With Tianjin polar ocean world design as an example,this paper discusses the bionic design method and its practical application in architecture design in terms of form,structure,and biological characteristic bionic.The polar ocean world boasts a well-found function aquarium,reasonable structure, and a bold form distinguished by its architecture individuality.The paper offers an analysis of the spatial morphology and the artistic conception of exhibition architecture from function,sculpt,and conception.
Objective To clone the gene of the toxic A chain of mistletoe protein with N-glyco-sidase activity.Methods Ammonium sulfate precipitation, affinity chromatography and cation exchange chromatography were employed to extract, isolate and purify the proteins with galactose-binding specificity from mistletoe [ Viscum coloratum (Komar.] Nakai) in Jilin province.After SDS-PAGE, the polypeptide bands were electroblotted onto polyvinylidene difluoride membrane for sequence analysis.The N-terminal sequences of mistletoe proteins were determined by automated Ed-man degradation.The cDNA fragment of A chain of one mistletoe protein was amplified by reverse transcription-polymerase chain reaction (RT-PCR) with the primers based on the N-terminal sequence results.Results Two new toxic proteins named CM-1, CM-2 were purified from V.coloratum.The search of Genbank showed that the deduced amino acid sequence of A chain of CM-1 was highly homologous with the A chains of mistletoe proteins in V.album.Conclusion The cDNA fragment encoding A chain of CM-1 was successfully cloned.
Objective:To determine the content of Astragoloside IV in Xiaoshuantong Granules by HPLC-ELSD. Methods:HPLC- ELSD separation was achieved. Results:The astragaloside Ⅳ showed good linearity (r=0.9999)in the range of 1.08μg-6.48μg, the average recovery was 100.2% with RSD 0.93%. Conclusions:The method is sensitive,reliable,accurate and repeatability,it can be used for quality control method of Xiaoshuantong granules.
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