Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is ...Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is facing serious challenge for the lack of canonical system of quality criterion for Chinese herbal compound so it has been a urgent problem to set up the quality control standards and reveal therapeutic basis of Chinese herbal compound.In order to give full play to the advantages of Chinese herbal compound,modern scientific and technological is used to research of Chinese herbal compound,especially the high performance liquid chromatography tandem mass spectrometry(HPLC-MS),because it is high sensitive,rapid,and obtain more information.It is very necessary that HPLC-MS is uesed to elucidate the effective components of basic substances of Chinese Herbal Compound,and endow traditional Chinese medicine with modern scientific connotation.展开更多
AIM: To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects.
[Method] This study aimed to determine trace amount of polycyclic aromatic hydrocarbons(PAHs) in urban sewage by using solid-phase extraction(SPE) coupled with high performance liquid chromatograph(HPLC).[Method] From...[Method] This study aimed to determine trace amount of polycyclic aromatic hydrocarbons(PAHs) in urban sewage by using solid-phase extraction(SPE) coupled with high performance liquid chromatograph(HPLC).[Method] From the aspects of solid-phase extraction column,elution solvent,elution volume,elution speed and so forth,the test conditions of SPE-HPLC method were optimized,and trace amount of PAHs in urban sewage was determined.[Result] The optimized solid-phase extraction conditions were SUPELCLEAN LC-18 solid-phase extraction column,methylene dichloride as elution solvent,15 ml elution volume,2 ml/min elution speed,5 ml/min loading speed,1 000 ml water with 200 ml methanol loading volume.Under the optimized extraction conditions,the recovery was high,namely 76.3%-105.2%;relative standard deviation was 3.8%-6.0%,showing good precision;detection limit was low,only 0.000 8-0.048 0 μg/L.[Conclusion] This method is user-friendly,with high sensitivity and good precision,and suitable for continuous determination of a large volume of water samples.展开更多
Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatograph...Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatography (HPLC) with a wavelength of UV (ultraviolet) 214 urn and a mobile phase of 18 mmol L-1 KH2PO4 buffer solution (pH 2.1). The thermal stability of organic acids was determined by comparing the recoveries of organic acids in different temperature treatments. The relationships between column temperature, flow rate or solvent pH and retention time were analyzed. At low solvent pH, separation efficiency of organic acids was increased by raising the flow rate of the solvent because of lowering the retention time of organic acids. High column temperature was unfavorable for the separation of organic acids. The separating effect can be enhanced through reducing column temperature in organic acid determination due to increasing retention time. High thermal stability of organic acids with low concentrations was observed at temperature of 40 ℃-45℃. Sensitivity and separation effect of organic acid determination by HPLC were clearly improved by a combination of raising flow rate and lowering column temperature at low solvent pH.展开更多
Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enri...Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L （S/N=3.3）. There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well.展开更多
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
Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and con...Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and convenient assay for screening antimicrotubule compounds in which in vitro microdialysis/high-performance liquid chromatography （HPLC） is used to monitor the binding of the compounds extracted from TCM Taxus cuspidata Siebold ＆ Zucc（Taxus） to microtubules is reported. It was observed that the extract of Taxus contains at least five compounds which have affinity interaction with microtubules by biological fingerprinting analysis, and they were identified as the taxoids of taxol, baccatin III, 10-deacetylbaccatin Ⅲ（10-DAB）, cephalomannine and 7-epi-10-deacetyltaxol （7-epi-10-DAT） based on the comparison of their high-performance liquid chromatographic/mass spectrometric and UV spectra with those of the standard samples, both assembly-promoting and disassembly-inhibiting characteristics of those compounds were evaluated. It was observed that baccatin Ⅲ and 10-DAB bound to microtubules and the binding degrees were influenced by GTP. Competitive binding behavior of taxol with other four taxoids to microtubules was also investigated.展开更多
A new reversed-phase high performance liquid chromatography method was developed to quantitate the activity of xanthine oxidase involved in milk fat globule membrane with xanthine as the substrate and the separation o...A new reversed-phase high performance liquid chromatography method was developed to quantitate the activity of xanthine oxidase involved in milk fat globule membrane with xanthine as the substrate and the separation of product (uric acid). The increment of uric acid in the reaction system was used to calculate the total activity of XO. The optimized assay conditions, linearity of detection, recovery of uric acid and chromatogram were developed in text, indicating this method is simple, rapid and efficient. It is an alternative potential method for the determination of the activity of XO in milk.展开更多
A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chine...A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chinese medicine, Loulu. The factors influencing separation performance were investigated and optimized. Under the optimal conditions, the contents of ecdysterone in Loulu were determined by HPLC system using MeOH-H_2O (40: 60,V/V) as the mobile phase at a flow rate of 1. 0 mL/min. The calibration curve was linear in the range of 0. 5~ 100 mg/L of ecdysterone concentrations. The detection limit of the analyte was 0. 11mol/L(3) with a precision of 0. 38% RSD (n=7 f c= 10. 0 mg/L). The average recovery of the method was 98. 7%. The proposed method has been applied to determine ecdysterone in practical samples, and the determined values by both external standard method and standard addition method were in good agreement. Compared to the traditional solid extraction method, the system proposed has the advantages of simple procedure, good reproducibility, minimum volume requirement, reduction of matrix interference and low contamination risk.展开更多
[Objectives]To accurately determine the naringin content in Rhizoma Drynariae.[Methods]The high performance liquid chromatography(HPLC)method was applied in the determination of the naringin content in Rhizoma Drynari...[Objectives]To accurately determine the naringin content in Rhizoma Drynariae.[Methods]The high performance liquid chromatography(HPLC)method was applied in the determination of the naringin content in Rhizoma Drynariae.The sample was sonicated at room temperature.The mobile phase was 0.1%phosphoric acid-acetonitrile(75∶25),detected by diode array detector at the wavelength of 284 nm,and quantified by external standard method.[Results]The linearity of naringin was good in the concentration range of 5-500μg/mL with a correlation coefficient of 0.9999.[Conclusions]This method has good linearity,easy operation,correctness and reproducibility as required,and is expected to provide a method for the determination of naringin content in Rhizoma Drynariae.展开更多
The aim of this work is optimizing the techniques to prepare pure cellulose microspheres, which are used as packing adsorbents for high-performance liquid chromatography. Thereupon, cellulose was dissolved in a pre-co...The aim of this work is optimizing the techniques to prepare pure cellulose microspheres, which are used as packing adsorbents for high-performance liquid chromatography. Thereupon, cellulose was dissolved in a pre-cooled NaOH/urea solution, from which various-size microspheres were prepared. The volume-average diameters were controlled approximately at 30 p,m, 8 ~tm and 4 pm grades when cyclohexane, liquid paraffin and pump oil were used as dispersants, respectively. The present investigations reveal that higher viscosity dispersant is suitable for the preparation of smaller-size microspheres, while larger size microspheres are prepared preferably using lower-viscosity dispersant. The chiral stationary phase derived from 8 μm grade microspheres can separate the enantiomers of efavirenz.展开更多
A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet de...A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet detection(UV)is proposed,and it was applied to determine the seven active compounds in Salvia Miltiorrhiza herb.SGSIL and ionic liquid[BMIM]BF4 were used as the adsorbent and the green elution reagent in the MSPD procedure.Several extraction conditions including type of filler and elution solvent,the volume of elution solvent,material liquid ratio were optimized.Under the optimum conditions,the SGSIL-MSPD-HPLC method showed a low limit of detection(LOD,S/N=3)of 0.0122-0.8788μg/mL for standard solution,limit of quantification(LOQ,S/N=10)of 0.0406-2.9292μg/mL for standard solution,wide linear range from 1.56 to 2000μg/mL for all compounds for standard solution,correlation coefficients(r)of more than 0.9990,acceptable reproducibility(relative standard deviations,RSDs<3.54%),and precision of RSDs<3.36%for intra-day,RSDs<3.50%for inter-day.The satisfactory recoveries ranged from 96.4 to 102.5,with RSDs less than 3.45%.The developed SGSIL-MSPD method is easier and more suitable for the determination of the seven active compounds in Salvia Miltiorrhiza herb than the traditional ultrasonic extraction.It was an effective and efficient method for the extraction and quantification of the seven active compounds in traditional Chinese herbal samples.展开更多
A simple isocratic HPLC technique has been developed for the quantitative analysis of phenolic acids (PAs) in fruits and vegetables. Nine benzoic and cinnamic acid derivatives were separated in less than 30 min, and t...A simple isocratic HPLC technique has been developed for the quantitative analysis of phenolic acids (PAs) in fruits and vegetables. Nine benzoic and cinnamic acid derivatives were separated in less than 30 min, and the resolution was all more than 1.23. The ranges of linearity for PAs standards were 0.2-100 ng, even up to 600 ng (r = 0.983-1.000) and the detection limits were 0.02-0.24 mg/kg. Samples of fresh vegetables and fruits were extracted with 80% mcthanol and ethyl acetate, then purified with C18 Sep-Pak cartridge and determined by HPLC. This method was applied to the determination of PAs in 7 kinds of fruits and vegetables, i.e., apple, pear, Chinese cabbage, cauliflower, turnip, soybean sprout and white grape wine. The content of the 9 PAs varied widely in the 7 kinds ol'foods studied. The average concentrations ofchlorogenic acid in apple (100.2 mg/kg) and pear (30.8 mg/kg) were quite high, and sinapinic acid was remarkable (42.5 mg/kg) in Chinese cabbage, and protocatechuic acid had the highest concentration of all the PAs in white wine.展开更多
Lemon oils are broadly used as flavoring agents in beverages,foods,cosmetics and pharmaceuticals,yet the adulteration of natural,particularly cold pressed lemon oils is very common in the industry due to its unmet dem...Lemon oils are broadly used as flavoring agents in beverages,foods,cosmetics and pharmaceuticals,yet the adulteration of natural,particularly cold pressed lemon oils is very common in the industry due to its unmet demand and high cost.Nowadays,most quality control(QC)analysis of lemon oils is conducted by gas chromatography(GC)analysis,which is far from a reliable method.Oxygen heterocyclic compounds(OHCs)in non-volatile fraction are gaining increasing attention in authentication process because of the nearly finger-printing profiles of OHCs in cold pressed citrus essential oils.Our goal in this study was to identify OHCs using high performance liquid chromatography(HPLC)in lemon oils,establish OHC profiles,perform stepwise logistic regression analysis(SLRA)and build effective predicting model and further determine adulterated lemon oils by referencing the OHC profiles and established models.After HPLC analyses,profiling and SLRA modeling of 154 OHCs samples of industrial lemon oils,we found that the combination of isopimpinellin and total OHC concentration are essential and robust predictors to differentiate authentic samples from adulterated lemon oils with a success rate of 98%from the 5-fold cross validation.This study provided a reliable and efficient method in determining the authenticity of lemon oils.展开更多
[Objectives]To make simultaneous determination of vitamin K_(1)(VK_(1))and vitamin K_(2)(VK_(2),mainly MK-4,MK-7 and MK-9)in milk and dairy products.[Methods]A high performance liquid chromatographic method was develo...[Objectives]To make simultaneous determination of vitamin K_(1)(VK_(1))and vitamin K_(2)(VK_(2),mainly MK-4,MK-7 and MK-9)in milk and dairy products.[Methods]A high performance liquid chromatographic method was developed for the simultaneous determination of vitamin K_(1)(VK_(1))and vitamin K_(2)(VK_(2),mainly MK-4,MK-7 and MK-9)in milk and dairy products.After enzymatic digestion,the samples were extracted with hexane for VK_(1),MK-4,MK-7 and MK-9,subjected to gradient elution at excitation wavelength 243 nm and emission wavelength 430 nm,detected by high performance liquid chromatography with fluorescence detector and quantified by external standard method.[Results]The linearity of VK_(1),MK-4,MK-7 and MK-9 was good in the concentration range of 2.5-1000 ng/mL with the correlation coefficients greater than 0.999;The relative standard deviations(RSD)of VK_(1),MK-4,MK-7 and MK-9 in milk powder,liquid milk and yogurt were 1.32%-5.05%,1.10%-2.48% and 2.20%-3.47%,respectively;the recovery rates of VK_(1),MK-4,MK-7 and MK-9 at different levels in milk powder,liquid milk and yogurt were 81.1%-108%,81.8%-103%and 82.1%-99.2%,respectively.[Conclusions]The method is rapid,accurate,reproducible and capable of simultaneous determination of VK_(1),MK-4,MK-7 and MK-9.展开更多
文摘Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is facing serious challenge for the lack of canonical system of quality criterion for Chinese herbal compound so it has been a urgent problem to set up the quality control standards and reveal therapeutic basis of Chinese herbal compound.In order to give full play to the advantages of Chinese herbal compound,modern scientific and technological is used to research of Chinese herbal compound,especially the high performance liquid chromatography tandem mass spectrometry(HPLC-MS),because it is high sensitive,rapid,and obtain more information.It is very necessary that HPLC-MS is uesed to elucidate the effective components of basic substances of Chinese Herbal Compound,and endow traditional Chinese medicine with modern scientific connotation.
基金Supported by National Natural Science Foundation of China,Grant No.81360356Scientific Research Foundation of Xinjiang Medical University,Grant No.XJC201221
文摘AIM: To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects.
基金Supported by National Science and Technology Key Project of Water Pollution Control and Management (2012ZX07209-003)
文摘[Method] This study aimed to determine trace amount of polycyclic aromatic hydrocarbons(PAHs) in urban sewage by using solid-phase extraction(SPE) coupled with high performance liquid chromatograph(HPLC).[Method] From the aspects of solid-phase extraction column,elution solvent,elution volume,elution speed and so forth,the test conditions of SPE-HPLC method were optimized,and trace amount of PAHs in urban sewage was determined.[Result] The optimized solid-phase extraction conditions were SUPELCLEAN LC-18 solid-phase extraction column,methylene dichloride as elution solvent,15 ml elution volume,2 ml/min elution speed,5 ml/min loading speed,1 000 ml water with 200 ml methanol loading volume.Under the optimized extraction conditions,the recovery was high,namely 76.3%-105.2%;relative standard deviation was 3.8%-6.0%,showing good precision;detection limit was low,only 0.000 8-0.048 0 μg/L.[Conclusion] This method is user-friendly,with high sensitivity and good precision,and suitable for continuous determination of a large volume of water samples.
文摘Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatography (HPLC) with a wavelength of UV (ultraviolet) 214 urn and a mobile phase of 18 mmol L-1 KH2PO4 buffer solution (pH 2.1). The thermal stability of organic acids was determined by comparing the recoveries of organic acids in different temperature treatments. The relationships between column temperature, flow rate or solvent pH and retention time were analyzed. At low solvent pH, separation efficiency of organic acids was increased by raising the flow rate of the solvent because of lowering the retention time of organic acids. High column temperature was unfavorable for the separation of organic acids. The separating effect can be enhanced through reducing column temperature in organic acid determination due to increasing retention time. High thermal stability of organic acids with low concentrations was observed at temperature of 40 ℃-45℃. Sensitivity and separation effect of organic acid determination by HPLC were clearly improved by a combination of raising flow rate and lowering column temperature at low solvent pH.
基金Project supported by the National Natural Science Foundation of China (No.20437020)Major Research Program of Chinese Academy of Sciences (No.KZCX3-SW-432).
文摘Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L （S/N=3.3）. There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well.
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.
基金the National Natural Science Foundation of China(No.90709021)Knowledge Innovation Program of Chi-nese Academy of Sciences(No.KJCX2.YW.HO9)
文摘Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and convenient assay for screening antimicrotubule compounds in which in vitro microdialysis/high-performance liquid chromatography （HPLC） is used to monitor the binding of the compounds extracted from TCM Taxus cuspidata Siebold ＆ Zucc（Taxus） to microtubules is reported. It was observed that the extract of Taxus contains at least five compounds which have affinity interaction with microtubules by biological fingerprinting analysis, and they were identified as the taxoids of taxol, baccatin III, 10-deacetylbaccatin Ⅲ（10-DAB）, cephalomannine and 7-epi-10-deacetyltaxol （7-epi-10-DAT） based on the comparison of their high-performance liquid chromatographic/mass spectrometric and UV spectra with those of the standard samples, both assembly-promoting and disassembly-inhibiting characteristics of those compounds were evaluated. It was observed that baccatin Ⅲ and 10-DAB bound to microtubules and the binding degrees were influenced by GTP. Competitive binding behavior of taxol with other four taxoids to microtubules was also investigated.
文摘A new reversed-phase high performance liquid chromatography method was developed to quantitate the activity of xanthine oxidase involved in milk fat globule membrane with xanthine as the substrate and the separation of product (uric acid). The increment of uric acid in the reaction system was used to calculate the total activity of XO. The optimized assay conditions, linearity of detection, recovery of uric acid and chromatogram were developed in text, indicating this method is simple, rapid and efficient. It is an alternative potential method for the determination of the activity of XO in milk.
基金Education Ministy Foundation for Chinese Returned Scholars and Nature Science Foundation of Hubeiprovince!98J054
文摘A flow injection (FI) micro-column system coupled with high performance liquid chromatography (HPLC) was proposed for the pre-separation and determination of active organic component (ecdysterone) in traditional Chinese medicine, Loulu. The factors influencing separation performance were investigated and optimized. Under the optimal conditions, the contents of ecdysterone in Loulu were determined by HPLC system using MeOH-H_2O (40: 60,V/V) as the mobile phase at a flow rate of 1. 0 mL/min. The calibration curve was linear in the range of 0. 5~ 100 mg/L of ecdysterone concentrations. The detection limit of the analyte was 0. 11mol/L(3) with a precision of 0. 38% RSD (n=7 f c= 10. 0 mg/L). The average recovery of the method was 98. 7%. The proposed method has been applied to determine ecdysterone in practical samples, and the determined values by both external standard method and standard addition method were in good agreement. Compared to the traditional solid extraction method, the system proposed has the advantages of simple procedure, good reproducibility, minimum volume requirement, reduction of matrix interference and low contamination risk.
文摘[Objectives]To accurately determine the naringin content in Rhizoma Drynariae.[Methods]The high performance liquid chromatography(HPLC)method was applied in the determination of the naringin content in Rhizoma Drynariae.The sample was sonicated at room temperature.The mobile phase was 0.1%phosphoric acid-acetonitrile(75∶25),detected by diode array detector at the wavelength of 284 nm,and quantified by external standard method.[Results]The linearity of naringin was good in the concentration range of 5-500μg/mL with a correlation coefficient of 0.9999.[Conclusions]This method has good linearity,easy operation,correctness and reproducibility as required,and is expected to provide a method for the determination of naringin content in Rhizoma Drynariae.
基金Funded by National Natural Science Foundation of China(Nos.50973086 and 51273073)Hubei Provincial Department of Education of China(No.Z20081501)
文摘The aim of this work is optimizing the techniques to prepare pure cellulose microspheres, which are used as packing adsorbents for high-performance liquid chromatography. Thereupon, cellulose was dissolved in a pre-cooled NaOH/urea solution, from which various-size microspheres were prepared. The volume-average diameters were controlled approximately at 30 p,m, 8 ~tm and 4 pm grades when cyclohexane, liquid paraffin and pump oil were used as dispersants, respectively. The present investigations reveal that higher viscosity dispersant is suitable for the preparation of smaller-size microspheres, while larger size microspheres are prepared preferably using lower-viscosity dispersant. The chiral stationary phase derived from 8 μm grade microspheres can separate the enantiomers of efavirenz.
基金This research was supported by Special Research Fund for Young Doctors of Qiqihar Medical University(QMSI2020B-03,hosted by Wenjing Li).
文摘A low cost,rapid and sensitive preparation method of silica gel supported ionic liquid(SGSIL)combined with matrix solid phase dispersion(MSPD)followed by high performance liquid chromatography(HPLC)with ultraviolet detection(UV)is proposed,and it was applied to determine the seven active compounds in Salvia Miltiorrhiza herb.SGSIL and ionic liquid[BMIM]BF4 were used as the adsorbent and the green elution reagent in the MSPD procedure.Several extraction conditions including type of filler and elution solvent,the volume of elution solvent,material liquid ratio were optimized.Under the optimum conditions,the SGSIL-MSPD-HPLC method showed a low limit of detection(LOD,S/N=3)of 0.0122-0.8788μg/mL for standard solution,limit of quantification(LOQ,S/N=10)of 0.0406-2.9292μg/mL for standard solution,wide linear range from 1.56 to 2000μg/mL for all compounds for standard solution,correlation coefficients(r)of more than 0.9990,acceptable reproducibility(relative standard deviations,RSDs<3.54%),and precision of RSDs<3.36%for intra-day,RSDs<3.50%for inter-day.The satisfactory recoveries ranged from 96.4 to 102.5,with RSDs less than 3.45%.The developed SGSIL-MSPD method is easier and more suitable for the determination of the seven active compounds in Salvia Miltiorrhiza herb than the traditional ultrasonic extraction.It was an effective and efficient method for the extraction and quantification of the seven active compounds in traditional Chinese herbal samples.
文摘A simple isocratic HPLC technique has been developed for the quantitative analysis of phenolic acids (PAs) in fruits and vegetables. Nine benzoic and cinnamic acid derivatives were separated in less than 30 min, and the resolution was all more than 1.23. The ranges of linearity for PAs standards were 0.2-100 ng, even up to 600 ng (r = 0.983-1.000) and the detection limits were 0.02-0.24 mg/kg. Samples of fresh vegetables and fruits were extracted with 80% mcthanol and ethyl acetate, then purified with C18 Sep-Pak cartridge and determined by HPLC. This method was applied to the determination of PAs in 7 kinds of fruits and vegetables, i.e., apple, pear, Chinese cabbage, cauliflower, turnip, soybean sprout and white grape wine. The content of the 9 PAs varied widely in the 7 kinds ol'foods studied. The average concentrations ofchlorogenic acid in apple (100.2 mg/kg) and pear (30.8 mg/kg) were quite high, and sinapinic acid was remarkable (42.5 mg/kg) in Chinese cabbage, and protocatechuic acid had the highest concentration of all the PAs in white wine.
文摘Lemon oils are broadly used as flavoring agents in beverages,foods,cosmetics and pharmaceuticals,yet the adulteration of natural,particularly cold pressed lemon oils is very common in the industry due to its unmet demand and high cost.Nowadays,most quality control(QC)analysis of lemon oils is conducted by gas chromatography(GC)analysis,which is far from a reliable method.Oxygen heterocyclic compounds(OHCs)in non-volatile fraction are gaining increasing attention in authentication process because of the nearly finger-printing profiles of OHCs in cold pressed citrus essential oils.Our goal in this study was to identify OHCs using high performance liquid chromatography(HPLC)in lemon oils,establish OHC profiles,perform stepwise logistic regression analysis(SLRA)and build effective predicting model and further determine adulterated lemon oils by referencing the OHC profiles and established models.After HPLC analyses,profiling and SLRA modeling of 154 OHCs samples of industrial lemon oils,we found that the combination of isopimpinellin and total OHC concentration are essential and robust predictors to differentiate authentic samples from adulterated lemon oils with a success rate of 98%from the 5-fold cross validation.This study provided a reliable and efficient method in determining the authenticity of lemon oils.
文摘[Objectives]To make simultaneous determination of vitamin K_(1)(VK_(1))and vitamin K_(2)(VK_(2),mainly MK-4,MK-7 and MK-9)in milk and dairy products.[Methods]A high performance liquid chromatographic method was developed for the simultaneous determination of vitamin K_(1)(VK_(1))and vitamin K_(2)(VK_(2),mainly MK-4,MK-7 and MK-9)in milk and dairy products.After enzymatic digestion,the samples were extracted with hexane for VK_(1),MK-4,MK-7 and MK-9,subjected to gradient elution at excitation wavelength 243 nm and emission wavelength 430 nm,detected by high performance liquid chromatography with fluorescence detector and quantified by external standard method.[Results]The linearity of VK_(1),MK-4,MK-7 and MK-9 was good in the concentration range of 2.5-1000 ng/mL with the correlation coefficients greater than 0.999;The relative standard deviations(RSD)of VK_(1),MK-4,MK-7 and MK-9 in milk powder,liquid milk and yogurt were 1.32%-5.05%,1.10%-2.48% and 2.20%-3.47%,respectively;the recovery rates of VK_(1),MK-4,MK-7 and MK-9 at different levels in milk powder,liquid milk and yogurt were 81.1%-108%,81.8%-103%and 82.1%-99.2%,respectively.[Conclusions]The method is rapid,accurate,reproducible and capable of simultaneous determination of VK_(1),MK-4,MK-7 and MK-9.
