In the present study, we developed and validated a simple and sensitive gradient elution liquid chromatography tandem mass spectrometry （LC-MS/MS） method for quantification of doxorubicin in rabbit plasma. Daunorubi...In the present study, we developed and validated a simple and sensitive gradient elution liquid chromatography tandem mass spectrometry （LC-MS/MS） method for quantification of doxorubicin in rabbit plasma. Daunorubicin was used as an internal standard （IS）. The doxorubicin and IS were extracted with ethyl acetate from plasma samples. The chromatographic separations were achieved on a C18 column （2.1 mm×50 mm, 2.5μm） configured with a C18 guard column （2.1 mm×10 mm, 2.5 μm）. The mobile phase of 0.1% formic acid-water solution and acetonitrile was delivered using a gradient elution program at a flow rate of 0.4 mL/min. The temperature for column was maintained at 40 ℃. The electrospray ionization （ESI） source was operated in the positive ion mode, and the quantification was conducted using multiple reaction monitoring （MRM） of the transitions m/z 544.07→396.96 and m/z 528.06→321.05 for doxorubicin and IS, respectively. The calibration curve of doxorubicin was linear （r 〉 0.999） within the range of 2-600 ng/mL. The lower limit of quantification was 2 ng/mL. The relative errors of intra-day and inter-day accuracies ranged from -2.48% to 0.18% and from -3.78% to 1.94%, respectively. The relative standard deviations of intra-day and inter-day precisions were less than 8.65% and 6.41%, respectively. The method exhibited satisfactory results in terms of specificity, sensitivity, matrix effect, recovery and stability. The newly developed LC-MS/MS method was reliable to monitor doxorubicin concentrations in rabbit plasma.展开更多
This study developed a method to perform the simultaneous concentration and selective separation of 66 （ultra） trace persistent toxic substances in Antarctic waters. The substances included 30 polychlorinated biphen...This study developed a method to perform the simultaneous concentration and selective separation of 66 （ultra） trace persistent toxic substances in Antarctic waters. The substances included 30 polychlorinated biphenyls, 17 organochlorine pesticides, 16 polycyclic aromatic hydrocarbons, 3 hexabromocyclododecanes. Solid phase extraction was performed using a C18 membrane and silica gel column. Gradient elution was conducted using organic solvents with different polarities; as a result, the efficiency of the C18 film is improved and the interferences from impurities and target compounds are eliminated. Extracts were subsequently analyzed through gas chromatography or liquid and gas chromatography coupled to tandem mass spectrometry. Method validation yielded the following values： recoveries of all target analytes in the Antarctic water ranged from 87.3% to 117.6% and reproducibility as percent relative standard deviation was lower than 5%. Quantification limits ranged from 0.004 μg L^-1 to 0.030 μg L^-1. The established method improved the recoveries and reduced the limits of detection. Results indicated the method exhibited good performance in the simultaneous concentration and selective separation of 66 （ultra） trace organic pollutants; Therefore, the proposed sample pretreatment can potentially eliminate the effects of various classes of impurities to some extent.展开更多
The separation optimization of nine organic and inorganic anions in tobacco leaves using gradient ion chromatography by response surface methodology was investigated.In order to achieve this goal the usefulness of the...The separation optimization of nine organic and inorganic anions in tobacco leaves using gradient ion chromatography by response surface methodology was investigated.In order to achieve this goal the usefulness of the chromatographic response function（CRF） for the evaluation of the two different chromatographic performance goals（resolution and analysis time） was tested. The experiments were performed according to a Box-Behnken design response surface experimental design.展开更多
An algorithm capable of predicting and optimizing the gradient separation of LC×LC system was developed in this paper.Two groups of structural analogues,five ginsenosides as well as eight bisphenols,which were di...An algorithm capable of predicting and optimizing the gradient separation of LC×LC system was developed in this paper.Two groups of structural analogues,five ginsenosides as well as eight bisphenols,which were difficult to discriminate in routine analysis,were used to verify the effectiveness of the proposed algorithm in fast separation optimization.Average errors of retention times below 1%were found in the retention prediction for all types of gradient programs,implying that the theory could lead to high quality in prediction of the retention times under gradients elution.Meanwhile,84%of relative average deviations(RADs)between the predicted peak width and the measured ones were less than 20%.The larger deviation occurred at the time when the peak appeared while the gradient of the mobile phase changed,which led the deviations increased to 20%–42%.In all,method development and optimization for LC×LC tandem system was realized by the homemade user-friendly software.The present protocol may turn on great opportunities for the convenient method development in analysis of trace structural analogues in environmental,food and biological samples.展开更多
The basic principle of optimal method called “moving overlapping resolution mapping Method” to select the optimal binary mobile phase composition of multi-step linear gradient liquid chromatography is discussed with...The basic principle of optimal method called “moving overlapping resolution mapping Method” to select the optimal binary mobile phase composition of multi-step linear gradient liquid chromatography is discussed with simultaneously considering effects of position of solute inside the column and mobile phase composition on peak resolution and retention value, then a BASIC program based on this principle is developed in IBM-PC computer. The validities of both principle of optimization and BASIC program are confirmed by separation of samples Containing bile acids and PAHs in RP-HPLC.展开更多
Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine....Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine. Since the isocratic elution method cannot be applied successfully in TLC analysis for separating all the nucleoside components, the stepwise gradient elution has been developed in this work to separate eight nucleoside standards with success. In this way, quantitative analyses of the samples of Cordyceps sinensis were achieved via the pro-posed TLC procedure coupled with the scanning densitometric techniques of CAMAG and TLCQA methods for qualitative and quantitative analysis.展开更多
The movement of a particular component along an HPLC column is studied on the ba-sis of equilibrium equations. Numerical simulation of multi--step gradient elution HPLC isperformed by means o? a personal computer prog...The movement of a particular component along an HPLC column is studied on the ba-sis of equilibrium equations. Numerical simulation of multi--step gradient elution HPLC isperformed by means o? a personal computer program. The location x, as a fraction of thecolumn length, for a given time t o? each compound is calculated, the velocity and corre-sponding acceleration are given as well. Diagrams for x,dx/dt and d^2x/dt^2 versus t display themovement process of the different components along the HPLC column during gradient elu-tion. The prediction of the retention time and peak width, and the optimization for the multi-step gradient elution HPLC are all based on such simulation and the molecular structure ofthe. components is separated as well.展开更多
A model for predicting retention time of solutes under linear gradient elution conditions has been established. In this model, the theoretical expressions under different elution modes were derived and tested with the...A model for predicting retention time of solutes under linear gradient elution conditions has been established. In this model, the theoretical expressions under different elution modes were derived and tested with the retention behaviors of p hydroxybenzaldehyde, vanillin, biphenyl, phenanthrene in gradient elution. With taking into account the dwell time of the instrumental system, the theoretically predicted retention times agree well with those experimentally determined.展开更多
A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5...A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5 μm)column with gradient elution with methanol-acetonitrile at a flow rate 0.2 mL/min.The mass spectrometry was operated in the positive electrospray ionization mode.Quantity was performed using multiple reaction monitoring of the product ion transitions m/z153.0>m/z106(17eV) for 2-amino-4-nitrophenol and m/z153.0>m/z122(15eV) for 2-amino-5-nitrophenol.Linearity of peak was obtained over a range of concentration is from 0.2 to 100 mg/L.The limit is 0.2 mg/L of the method.The proposed method was accurate and rapid with wide linear range.The repeatability and the reproducibility of the method were excellent.It has been applied to detect the real with satisfactory results.展开更多
目的应用RP-HPLC对不同产地虎杖药材进行指纹图谱研究。方法K rom as il C18色谱柱(150 mm×4.6mm,5μm),乙腈-水二元梯度洗脱,体积流量:1 mL/m in,检测波长303 nm。结果根据选择的色谱条件制订了不同产地虎杖药材的指纹图谱。结论...目的应用RP-HPLC对不同产地虎杖药材进行指纹图谱研究。方法K rom as il C18色谱柱(150 mm×4.6mm,5μm),乙腈-水二元梯度洗脱,体积流量:1 mL/m in,检测波长303 nm。结果根据选择的色谱条件制订了不同产地虎杖药材的指纹图谱。结论色谱图对各产地虎杖药材中各成分得到了很好的分离,可作为虎杖药材的专属性指纹图谱。展开更多
基金National Natural Science Foundation of China（ Grant No.81571779）.
文摘In the present study, we developed and validated a simple and sensitive gradient elution liquid chromatography tandem mass spectrometry （LC-MS/MS） method for quantification of doxorubicin in rabbit plasma. Daunorubicin was used as an internal standard （IS）. The doxorubicin and IS were extracted with ethyl acetate from plasma samples. The chromatographic separations were achieved on a C18 column （2.1 mm×50 mm, 2.5μm） configured with a C18 guard column （2.1 mm×10 mm, 2.5 μm）. The mobile phase of 0.1% formic acid-water solution and acetonitrile was delivered using a gradient elution program at a flow rate of 0.4 mL/min. The temperature for column was maintained at 40 ℃. The electrospray ionization （ESI） source was operated in the positive ion mode, and the quantification was conducted using multiple reaction monitoring （MRM） of the transitions m/z 544.07→396.96 and m/z 528.06→321.05 for doxorubicin and IS, respectively. The calibration curve of doxorubicin was linear （r 〉 0.999） within the range of 2-600 ng/mL. The lower limit of quantification was 2 ng/mL. The relative errors of intra-day and inter-day accuracies ranged from -2.48% to 0.18% and from -3.78% to 1.94%, respectively. The relative standard deviations of intra-day and inter-day precisions were less than 8.65% and 6.41%, respectively. The method exhibited satisfactory results in terms of specificity, sensitivity, matrix effect, recovery and stability. The newly developed LC-MS/MS method was reliable to monitor doxorubicin concentrations in rabbit plasma.
基金financially supported by the National Natural Science Foundation of China(No.21377032)the Chinese Polar Environment Comprehensive Investigation and Assessment Program(Nos.2014-02-01,2014-03-04,2014-04-01,2014-04-03)+1 种基金the Marine Public Welfare Scientific Research Projects(No.201105013)the Foundation of Polar Science Key Laboratory,SOA,China(No.KP201208)
文摘This study developed a method to perform the simultaneous concentration and selective separation of 66 （ultra） trace persistent toxic substances in Antarctic waters. The substances included 30 polychlorinated biphenyls, 17 organochlorine pesticides, 16 polycyclic aromatic hydrocarbons, 3 hexabromocyclododecanes. Solid phase extraction was performed using a C18 membrane and silica gel column. Gradient elution was conducted using organic solvents with different polarities; as a result, the efficiency of the C18 film is improved and the interferences from impurities and target compounds are eliminated. Extracts were subsequently analyzed through gas chromatography or liquid and gas chromatography coupled to tandem mass spectrometry. Method validation yielded the following values： recoveries of all target analytes in the Antarctic water ranged from 87.3% to 117.6% and reproducibility as percent relative standard deviation was lower than 5%. Quantification limits ranged from 0.004 μg L^-1 to 0.030 μg L^-1. The established method improved the recoveries and reduced the limits of detection. Results indicated the method exhibited good performance in the simultaneous concentration and selective separation of 66 （ultra） trace organic pollutants; Therefore, the proposed sample pretreatment can potentially eliminate the effects of various classes of impurities to some extent.
基金financially supported by National Natural Science Foundation of China(Nos.20775070. J0830413)Zhejiang Provincial Natural Science Foundation of China(No.R4080124)
文摘The separation optimization of nine organic and inorganic anions in tobacco leaves using gradient ion chromatography by response surface methodology was investigated.In order to achieve this goal the usefulness of the chromatographic response function（CRF） for the evaluation of the two different chromatographic performance goals（resolution and analysis time） was tested. The experiments were performed according to a Box-Behnken design response surface experimental design.
基金supported by National Natural Science Foundation of China(Nos.82174090,22176085,21874065,21577057)Natural Science Foundation for Colleges of Jiangsu(No.21KJA360007)+2 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Jiangsu Qinglan ProjectJiangsu“333”Project。
文摘An algorithm capable of predicting and optimizing the gradient separation of LC×LC system was developed in this paper.Two groups of structural analogues,five ginsenosides as well as eight bisphenols,which were difficult to discriminate in routine analysis,were used to verify the effectiveness of the proposed algorithm in fast separation optimization.Average errors of retention times below 1%were found in the retention prediction for all types of gradient programs,implying that the theory could lead to high quality in prediction of the retention times under gradients elution.Meanwhile,84%of relative average deviations(RADs)between the predicted peak width and the measured ones were less than 20%.The larger deviation occurred at the time when the peak appeared while the gradient of the mobile phase changed,which led the deviations increased to 20%–42%.In all,method development and optimization for LC×LC tandem system was realized by the homemade user-friendly software.The present protocol may turn on great opportunities for the convenient method development in analysis of trace structural analogues in environmental,food and biological samples.
文摘The basic principle of optimal method called “moving overlapping resolution mapping Method” to select the optimal binary mobile phase composition of multi-step linear gradient liquid chromatography is discussed with simultaneously considering effects of position of solute inside the column and mobile phase composition on peak resolution and retention value, then a BASIC program based on this principle is developed in IBM-PC computer. The validities of both principle of optimization and BASIC program are confirmed by separation of samples Containing bile acids and PAHs in RP-HPLC.
基金the Research Committee of The Hong Kong Polytechnic University(No.G-V877)the Area of Excellence(AoE)of"Chinese Medicine Research and Further Development"of the University Grant Council(UGC)of Hong Kong Special Administrative Region(No.AoE/B-10/01)
文摘Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine. Since the isocratic elution method cannot be applied successfully in TLC analysis for separating all the nucleoside components, the stepwise gradient elution has been developed in this work to separate eight nucleoside standards with success. In this way, quantitative analyses of the samples of Cordyceps sinensis were achieved via the pro-posed TLC procedure coupled with the scanning densitometric techniques of CAMAG and TLCQA methods for qualitative and quantitative analysis.
文摘The movement of a particular component along an HPLC column is studied on the ba-sis of equilibrium equations. Numerical simulation of multi--step gradient elution HPLC isperformed by means o? a personal computer program. The location x, as a fraction of thecolumn length, for a given time t o? each compound is calculated, the velocity and corre-sponding acceleration are given as well. Diagrams for x,dx/dt and d^2x/dt^2 versus t display themovement process of the different components along the HPLC column during gradient elu-tion. The prediction of the retention time and peak width, and the optimization for the multi-step gradient elution HPLC are all based on such simulation and the molecular structure ofthe. components is separated as well.
基金theNationalNaturalScienceFoundationofChina (No .2 0 0 75 0 0 5 ) theGrantfromMinistryofScienceandTechnologytheNaturalScienceFoundationofHebeiProvince (No .2 0 2 0 96)
文摘A model for predicting retention time of solutes under linear gradient elution conditions has been established. In this model, the theoretical expressions under different elution modes were derived and tested with the retention behaviors of p hydroxybenzaldehyde, vanillin, biphenyl, phenanthrene in gradient elution. With taking into account the dwell time of the instrumental system, the theoretically predicted retention times agree well with those experimentally determined.
文摘A new method of 2-amino-4-nitrophenol and 2-amino-5-nitrophenol in hair dye determined by liquid chromatography-mass spectrometry.Chromatographic separation was carried out on a Atlantis C18 (2.1 mm i.d.×150 mm,5 μm)column with gradient elution with methanol-acetonitrile at a flow rate 0.2 mL/min.The mass spectrometry was operated in the positive electrospray ionization mode.Quantity was performed using multiple reaction monitoring of the product ion transitions m/z153.0>m/z106(17eV) for 2-amino-4-nitrophenol and m/z153.0>m/z122(15eV) for 2-amino-5-nitrophenol.Linearity of peak was obtained over a range of concentration is from 0.2 to 100 mg/L.The limit is 0.2 mg/L of the method.The proposed method was accurate and rapid with wide linear range.The repeatability and the reproducibility of the method were excellent.It has been applied to detect the real with satisfactory results.
文摘目的应用RP-HPLC对不同产地虎杖药材进行指纹图谱研究。方法K rom as il C18色谱柱(150 mm×4.6mm,5μm),乙腈-水二元梯度洗脱,体积流量:1 mL/m in,检测波长303 nm。结果根据选择的色谱条件制订了不同产地虎杖药材的指纹图谱。结论色谱图对各产地虎杖药材中各成分得到了很好的分离,可作为虎杖药材的专属性指纹图谱。
