A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compo...A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation（ZFP）.The monitoring wavelengths were 254,275 and 328 nm.Under the optimum conditions,good separation was achieved,and the assay was fully validated in respect of precision,repeatability and accuracy.The proposed method was successfully applied to quantify the six ingredients in 31 batches of ZFP samples and evaluate the variation by hierarchical cluster analysis（HCA）,which demonstrated significant variations on the content of these compounds in the samples from different manufacturers with different preparation procedures.The developed HPLC method can be used as a valid analytical method to evaluate the intrinsic quality of this preparation.展开更多
[Objective]The paper was to establish a method for determining AF and AFG in red ginseng.[Method]A new simple,rapid and sensitive method for simultaneous determination of two amadori compounds,arginyl-fructose(AF)and ...[Objective]The paper was to establish a method for determining AF and AFG in red ginseng.[Method]A new simple,rapid and sensitive method for simultaneous determination of two amadori compounds,arginyl-fructose(AF)and arginyl-fructosyl-glucose(AFG),in extracts of three kinds of ginseng preparations was developed and validated using high performance liquid chromatography with evaporative light scattering detector(HPLC-ELSD).Two target analytes were efficiently separated by Prevail CTM18 column(4.6 mm×250 mm,5μm)at the flow rate of 0.8 mL/min within 15 min of single chromatographic run.[Result]Under optimized conditions,the detection limits were 0.015 and 0.02 mg/mL for AF and AFG,respectively.Calibration curves of peak area for two analytes were linear over three orders of magnitude with the correlation coefficients greater than 0.999.The average recoveries,precision,reproducibility and stability for two analytes(AF and AFG)were 99.5% and 100.9%,0.43% and 0.47%,0.46% and 0.43%,0.41% and 0.49%,respectively.[Conclusion]This method was successfully applied for quantifying AF and AFG in red ginseng and the method was efficient,sensitive and accurate.展开更多
Egg yolk phosphatidylcholine(EYPC) is being widely used in food and pharmaceutical industries nowadays owing to its surface activity,pharmaceutical usefulness,and so on.Common determination methods of phospholipids we...Egg yolk phosphatidylcholine(EYPC) is being widely used in food and pharmaceutical industries nowadays owing to its surface activity,pharmaceutical usefulness,and so on.Common determination methods of phospholipids were based on the American Oil Chemists' Society(AOCS) Official Method Ja7b-91,in which n-hexane/2-propanol/acetate buffer was used as the mobile phase.In order to achieve desired results,gradient elu-tion or buffer solution was used,which made the detection process more complicated.Moreover,water or buffer solution could affect the silica gel column both on its lifespan and the separation efficiency significantly.In this study,different mobile phase and detector were used to simplify EYPC analyzing process instead of using water within the mobile phase.The optimized HPLC operating conditions are as follows:pure methanol as a mobile phase,flow rate of 1.0 ml·min-1,silica gel column(250 mm×4.6 mm,5 μm,Inertsil GLTM),column temperature 30 ℃ and low temperature evaporative light scattering detector(40 ℃,0.35 MPa) as used.Under this optimal condition,the linear relative coefficient of the standard curve is 0.998 and the recovery was in the range of 96.83%-101.58% with a relative standard deviation of 1.79%(n=6).展开更多
A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulatio...A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulations(injections,capsules and tablets)without any pretreatment or derivatization step.Azithromycin,degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate(0.05 M,pH 8.0)and acetonitrile(60:40,v/v)in an isocratic mode at 0.8 ml/min flow rate.Parameters of ELSD were 60C for evaporation temperature and 50 psi for pressure of carrier gas(air).A logarithmic calibration curve was obtained from 50.93 to 509.30 mg/ml(r¼0.9996)for azithromycin,with the limit of detection(LOD)of 6.75 mg/ml(S/n¼3)and the limit of quantification of 22.50 mg/ml(S/n¼10).The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations(recovery 99e102%,RSD<1.2%,n¼3).No significant difference(t-test)was found between the results of the developed HPLCeELSD method and the HPLCeUV or microbiological method.展开更多
Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχf...Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.展开更多
文摘A simple and accurate high-performance liquid chromatography（HPLC）coupled with diode array detector（DAD）and evaporative light scattering detector（ELSD）was established for the determination of six bioactive compounds in Zhenqi Fuzheng preparation（ZFP）.The monitoring wavelengths were 254,275 and 328 nm.Under the optimum conditions,good separation was achieved,and the assay was fully validated in respect of precision,repeatability and accuracy.The proposed method was successfully applied to quantify the six ingredients in 31 batches of ZFP samples and evaluate the variation by hierarchical cluster analysis（HCA）,which demonstrated significant variations on the content of these compounds in the samples from different manufacturers with different preparation procedures.The developed HPLC method can be used as a valid analytical method to evaluate the intrinsic quality of this preparation.
文摘[Objective]The paper was to establish a method for determining AF and AFG in red ginseng.[Method]A new simple,rapid and sensitive method for simultaneous determination of two amadori compounds,arginyl-fructose(AF)and arginyl-fructosyl-glucose(AFG),in extracts of three kinds of ginseng preparations was developed and validated using high performance liquid chromatography with evaporative light scattering detector(HPLC-ELSD).Two target analytes were efficiently separated by Prevail CTM18 column(4.6 mm×250 mm,5μm)at the flow rate of 0.8 mL/min within 15 min of single chromatographic run.[Result]Under optimized conditions,the detection limits were 0.015 and 0.02 mg/mL for AF and AFG,respectively.Calibration curves of peak area for two analytes were linear over three orders of magnitude with the correlation coefficients greater than 0.999.The average recoveries,precision,reproducibility and stability for two analytes(AF and AFG)were 99.5% and 100.9%,0.43% and 0.47%,0.46% and 0.43%,0.41% and 0.49%,respectively.[Conclusion]This method was successfully applied for quantifying AF and AFG in red ginseng and the method was efficient,sensitive and accurate.
文摘Egg yolk phosphatidylcholine(EYPC) is being widely used in food and pharmaceutical industries nowadays owing to its surface activity,pharmaceutical usefulness,and so on.Common determination methods of phospholipids were based on the American Oil Chemists' Society(AOCS) Official Method Ja7b-91,in which n-hexane/2-propanol/acetate buffer was used as the mobile phase.In order to achieve desired results,gradient elu-tion or buffer solution was used,which made the detection process more complicated.Moreover,water or buffer solution could affect the silica gel column both on its lifespan and the separation efficiency significantly.In this study,different mobile phase and detector were used to simplify EYPC analyzing process instead of using water within the mobile phase.The optimized HPLC operating conditions are as follows:pure methanol as a mobile phase,flow rate of 1.0 ml·min-1,silica gel column(250 mm×4.6 mm,5 μm,Inertsil GLTM),column temperature 30 ℃ and low temperature evaporative light scattering detector(40 ℃,0.35 MPa) as used.Under this optimal condition,the linear relative coefficient of the standard curve is 0.998 and the recovery was in the range of 96.83%-101.58% with a relative standard deviation of 1.79%(n=6).
基金National Natural Science Foundations of China(No.81173024)to professor Qiang Fu is gratefully acknowledged.The authors also thank Xi’an Insti-tute of Food and Drug Control for providing the facilities and necessary equipments.
文摘A simple high-performance liquid chromatography(HPLC)method coupled with an evaporative light scattering detector(ELSD)was developed for the determination of azithromycin in raw materials and pharmaceutical formulations(injections,capsules and tablets)without any pretreatment or derivatization step.Azithromycin,degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate(0.05 M,pH 8.0)and acetonitrile(60:40,v/v)in an isocratic mode at 0.8 ml/min flow rate.Parameters of ELSD were 60C for evaporation temperature and 50 psi for pressure of carrier gas(air).A logarithmic calibration curve was obtained from 50.93 to 509.30 mg/ml(r¼0.9996)for azithromycin,with the limit of detection(LOD)of 6.75 mg/ml(S/n¼3)and the limit of quantification of 22.50 mg/ml(S/n¼10).The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations(recovery 99e102%,RSD<1.2%,n¼3).No significant difference(t-test)was found between the results of the developed HPLCeELSD method and the HPLCeUV or microbiological method.
基金supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1607100,and 2022YFA1605000)the National Natural Science Foundation of China(Grant Nos.12322511,12175112,12005111,and 11725522)。
文摘Dark matter(DM)is a major constituent of the Universe.However,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to date.There is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target electrons.The examined PBH masses range from 1×10^(15)to 7×10^(16)g under the current limits of PBH abundance fPBH.Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×10^(-29)cm^(2)forχwith a mass■keV from our results.With the higher radiation background but lower energy threshold(160 eV),CDEX-10 fills a part of the gap in the previous work.If(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.
