At present,frequent outbreaks of bacteria and viruses have seriously affected people's normal lives.Therefore,the study of broad-spectrum antibacterial nanocomposites is very promising.However,most antibacterial m...At present,frequent outbreaks of bacteria and viruses have seriously affected people's normal lives.Therefore,the study of broad-spectrum antibacterial nanocomposites is very promising.However,most antibacterial materials have some disadvantages,such as single bactericidal mechanisms and unrepeatable use.Based on the current situation,a kind of nanocomposite with three structures of graphene oxide(GO),quaternary ammonium salt(QAs)and N-halamine was prepared,which showed synergistic effect to improve antibacterial activity and combined with a variety of sterilization mechanisms.Meanwhile,GO can provide richer ways of sterilization and high specific surface area,which is conducive to the grafting of quaternarized N-halamine.The advantages of physical sterilization of GO,charge adsorption of QAs,reuse of N-halamine and efficient sterilization are fully utilized.The results showed that the quaternarized N-halamine-grafted GO was obtained successfully.GO grafted with quaternarized N-halamine polymer showed strong speedy bactericidal activity against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)(99%).It had good storage and regeneration properties.展开更多
[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The ...[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food.展开更多
基金supported by the National Natural Science Foundation of China(No.51603020)the Jilin Province Science and Technology Natural Science Foundation Project of China(No.20180101193JC).
文摘At present,frequent outbreaks of bacteria and viruses have seriously affected people's normal lives.Therefore,the study of broad-spectrum antibacterial nanocomposites is very promising.However,most antibacterial materials have some disadvantages,such as single bactericidal mechanisms and unrepeatable use.Based on the current situation,a kind of nanocomposite with three structures of graphene oxide(GO),quaternary ammonium salt(QAs)and N-halamine was prepared,which showed synergistic effect to improve antibacterial activity and combined with a variety of sterilization mechanisms.Meanwhile,GO can provide richer ways of sterilization and high specific surface area,which is conducive to the grafting of quaternarized N-halamine.The advantages of physical sterilization of GO,charge adsorption of QAs,reuse of N-halamine and efficient sterilization are fully utilized.The results showed that the quaternarized N-halamine-grafted GO was obtained successfully.GO grafted with quaternarized N-halamine polymer showed strong speedy bactericidal activity against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)(99%).It had good storage and regeneration properties.
文摘[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food.
