A simple and sensitive ion-paring HPLC-MS/MS method with negative ion mode has been developed and validated for the quantification of SA in milk.The separation was performed on C18 column with a mobile phase consistin...A simple and sensitive ion-paring HPLC-MS/MS method with negative ion mode has been developed and validated for the quantification of SA in milk.The separation was performed on C18 column with a mobile phase consisting of 4 mmol/L tetrabutylammonium hydroxide-methanol at a flow rate of 0.2 mL/min under the gradient elution.The retention time of SA was 6.1 min.Triple-quadrupole MS/MS detection was operated in negative mode by monitoring the transition of m/z 308.1>87.1 for SA.Validation results indicated that the lower limit of quantification was 0.060 mg/L and the assay showed a linear range of 0.1-100 mg/L and gave a correlation coefficient(r) of 0.998.The relative standard deviations were less than 10% at all tested concentration levels.The method has been successfully applied to the analysis of SA in milk,milk powder and breast milk.展开更多
A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed. Chromatographic separations were performed on a...A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed. Chromatographic separations were performed on a reversed-phase silica-based monolithic column using 1-heptanesulfonic acid sodium-acetonitrile as mobile phase. The effects of ion-pair reagent and acetonitrile concentration on retention of the cations were investigated. The retention times of the cations accord with carbon number rule. The method has been successfully applied to the determination of four ionic liquids synthesized by organic chemistry laboratory.展开更多
In this work, we developed a highly sensitive method to detect melamine based on reversed phase liquid chromatography mass spectrometry. A mass spectrometry compatible ion pair, heptafluorobu-tyric acid(HFBA), was use...In this work, we developed a highly sensitive method to detect melamine based on reversed phase liquid chromatography mass spectrometry. A mass spectrometry compatible ion pair, heptafluorobu-tyric acid(HFBA), was used to separate melamine by reversed phase liquid chromatography prior to electrospray mass spectrometry. The incorporation of isotope internal standard and multiple reaction monitoring improved the accuracy and linearity of quantification. Based on this strategy, the method limit of quantification was 0.1 ng/g. The limits of quantification were 8 ng/g for liquid milk and 15 ng/g for dry milk powder. This method provided a reproducible and stable approach to sensitive detection and quantification of melamine.展开更多
文摘A simple and sensitive ion-paring HPLC-MS/MS method with negative ion mode has been developed and validated for the quantification of SA in milk.The separation was performed on C18 column with a mobile phase consisting of 4 mmol/L tetrabutylammonium hydroxide-methanol at a flow rate of 0.2 mL/min under the gradient elution.The retention time of SA was 6.1 min.Triple-quadrupole MS/MS detection was operated in negative mode by monitoring the transition of m/z 308.1>87.1 for SA.Validation results indicated that the lower limit of quantification was 0.060 mg/L and the assay showed a linear range of 0.1-100 mg/L and gave a correlation coefficient(r) of 0.998.The relative standard deviations were less than 10% at all tested concentration levels.The method has been successfully applied to the analysis of SA in milk,milk powder and breast milk.
基金supported by the Natural Science Foundation of Heilongjiang Province(No.B200909)the Program for Scientific and Technological Innovation Team Construction in Universities of Heilongjiang Province(No. 2011TD010)
文摘A method for rapid and simultaneous determination of imidazolium and pyridinium ionic liquid cations by ion-pair chromatography with ultraviolet detection was developed. Chromatographic separations were performed on a reversed-phase silica-based monolithic column using 1-heptanesulfonic acid sodium-acetonitrile as mobile phase. The effects of ion-pair reagent and acetonitrile concentration on retention of the cations were investigated. The retention times of the cations accord with carbon number rule. The method has been successfully applied to the determination of four ionic liquids synthesized by organic chemistry laboratory.
基金Supported by the National Natural Science Foundation of China (Grant No. 30425021)National High Technology Research and Development Program of China (Grant No. 2007AA02Z334)
文摘In this work, we developed a highly sensitive method to detect melamine based on reversed phase liquid chromatography mass spectrometry. A mass spectrometry compatible ion pair, heptafluorobu-tyric acid(HFBA), was used to separate melamine by reversed phase liquid chromatography prior to electrospray mass spectrometry. The incorporation of isotope internal standard and multiple reaction monitoring improved the accuracy and linearity of quantification. Based on this strategy, the method limit of quantification was 0.1 ng/g. The limits of quantification were 8 ng/g for liquid milk and 15 ng/g for dry milk powder. This method provided a reproducible and stable approach to sensitive detection and quantification of melamine.
