期刊文献+
共找到25,065篇文章
< 1 2 250 >
每页显示 20 50 100
Determination of Benzo[a]pyrene in Edible Oil by High Performance Liquid Chromatography-Fluorescence Detector (HPLC-FL)
1
作者 Guixia YANG Jie LIU +3 位作者 Xiujuan WANG Fenglan ZHANG Kun XIN Chunli KONG 《Agricultural Biotechnology》 2024年第2期8-9,19,共3页
In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Sc... In this study, an optimized high performance liquid chromatography-fluorescence detector (HPLC-FL) method for the determination of benzo[a]pyrene in edible oil was established. HPLC was performed with Thermo Fisher Scientific C18 column (250 mm×4.6 mm, 5 μm) as the chromatographic column and acetonitrile and water as the mobile phase, and the excitation wavelength and emission wavelength of fluorescence detector were 286 and 430 nm, respectively. The response was high, and the linear range was 0.5-10.0 ng/ml. The lowest limit of detection was 0.11 ng/ml, and the average recovery was 92.5%. This method is suitable for quantitative analysis of benzo[a]pyrene content in edible oil. 展开更多
关键词 BENZO[A]PYRENE high performance liquid chromatography Fluorescence detector
下载PDF
A High-Performance Liquid Chromatography Method for the Simultaneous Determination of Five Index Components in Danhong Injection
2
作者 Yun An Tian Tian +2 位作者 Qinglin Wang Xingchu Gong Chenchen Wang 《American Journal of Analytical Chemistry》 CAS 2023年第11期481-492,共12页
The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, a... The purpose of this study was to establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. The chromatographic method employed was as follows: the column was a Welch Ultimate XB-C18 column (250 mm × 4.6 mm, 10 μm), the mobile phase was a gradient elution of 0.4% formic acid aqueous solution (A) and acetonitrile (B), the detection wavelengths were 280 nm for sodium danshensu, protocatechuic aldehyde, and salvianolic acid B and 326 nm for 4-coumaric acid and rosmarinic acid, the sample volume was 10 μL, the flow rate was 1.0 mL/min, and the column temperature was 35°C. This method can realize the separation and determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid within 50 minutes. The linear relationships of the five peak areas and their concentrations are good (R2> 0.9997). The precision RSD values are all less than 1.0%. The reproducibility RSD values are all less than 1.3%. The stability RSD values are all less than 2.2%. The recovery values ranged from 92.4% to 99.4%. This method is simple, accurate, and reproducible. It can be used for the determination of sodium danshensu, protocatechuic aldehyde, rosmarinic acid, salvianolic acid B, and 4-coumaric acid in Danhong injection. 展开更多
关键词 Danhong Injection high performance liquid chromatography Phenolic Acid FLAVONOIDS
下载PDF
Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I. Development and Assessment of Chromatographic Conditions *1 被引量:4
3
作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1998年第2期97-104,共8页
Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile ph... Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids. 展开更多
关键词 high performance liquid chromatography organic acids root exudates SOYBEAN
下载PDF
Determination of AF and AFG in Red Ginseng by High Performance Liquid Chromatography with Evaporative Light Scattering Detector (HPLC-ELSD) 被引量:2
4
作者 Chen Wei He Da Shao Ying 《Animal Husbandry and Feed Science》 CAS 2019年第5期131-134,共4页
[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
关键词 high performance liquid chromatography Evaporative light scattering detector Amadori compounds Red ginseng
下载PDF
High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometric Analysis of Bilobalide and Ginkgolides in Ginkgo biloba L. Leaves 被引量:1
5
作者 卢定强 韦萍 +1 位作者 欧阳平凯 陈钧 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第2期26-30,共5页
The ginkgo terpenoids including bilobalide and ginkgolides are the main pharmaceutical components in the leaves or extracts of Ginkgo biloba L. In this paper, the analysis of bilobalide and ginkgolides in leaves of Gi... The ginkgo terpenoids including bilobalide and ginkgolides are the main pharmaceutical components in the leaves or extracts of Ginkgo biloba L. In this paper, the analysis of bilobalide and ginkgolides in leaves of Ginkgo biloba L. by high performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS) was carried out. The separation was performed on Inertsil ODS3 column with methanol-water (36:64) as mobile phase, with 1 mL·min -1 of flow rate at 35℃. Then the mass spectrum analysis was conducted by ZMD micromass electrospray ionization (ESI)-mass spectrometer (MS). The HPLC total ion chromatogram and selected ion chromatogram (with 325, 407, 423, 439 of m/z) of the sample and ESI-/MS mass spectra of the peaks in the chromatograms were obtained. So bilobalide, ginkgolide A, B, C and J in Ginkgo biloba L. leaves were identified. The method is easy and rapid, with a good accuracy. 展开更多
关键词 high performance liquid chromatography Electrospray ionization Mass spectrometry Ginkgo terpene lactones
下载PDF
Modernization of Chinese herbal compound and the high performance liquid chromatography tandem mass spectrometry (HPLC-MS)
6
作者 LI Wen-lan1,2,3,SUN Zhi1,2,DU Juan1,2(1.Engineering Research Center of natural antineoplastic drugs,Ministry of Education,Harbin 150076,China 2.Center of Research and Development on Life Sciences and Environmental Sciences,Harbin University of Commerce,Harbin 150076,China 3.Institute of Materia Medica and Postdoctoral Programme of Harbin University of Commerce,Harbin 150076,China) 《沈阳药科大学学报》 CAS CSCD 北大核心 2008年第S1期119-119,共1页
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
关键词 MODERNIZATION of Chinese HERBAL compound the high performance liquid chromatography tandem mass spectrometry(hplc-MS)
下载PDF
Analysis of Amino Acids in Houttuynia Cordata Thunb. by High Performance Liquid Chromatography-Diode Array Detector (HPLC-DAD)
7
作者 Xuan FENG Zhannan YANG +5 位作者 Zhu ZHENG Juan HU Xiaofang WEI Honghao HUO Cheng ZHAO Quling ZHANG 《Medicinal Plant》 CAS 2019年第2期28-34,共7页
[Objectives] The biologically active compounds of Houttuynia cordata Thunb. as a medicinal and edible plant are well documented. However, amino acid as an important indicator of the value of H. cordata is little repor... [Objectives] The biologically active compounds of Houttuynia cordata Thunb. as a medicinal and edible plant are well documented. However, amino acid as an important indicator of the value of H. cordata is little reported. [Methods] Amino acids of the H. cordata were analysed by pre-column derivatization with 2,4-dinitrochlorobenzne(CDNB) coupled to HPLC/DAD. The optimized conditions of the amino acids derivatized by CDNB were followed: 110 ℃ of hydrolysis temperature, 1∶12 of the equivalent proportion between amino acid and CDNB, 80 min of derivatization reaction time and 80 ℃ of derivatization reaction temperature. The method was used to determine the amino acids of H. cordata samples from 11 different geographical sites in Guizhou. [Results] The results suggested that the contents of 17 amino acids were quite variable at different H. cordata samples. [Conclusions] This study will provide a basis for the quality evaluation of H. cordata nutrition. 展开更多
关键词 Houttuynia cordata Thunb. AMINO acid high performance liquid chromatography MEDICINAL plant
下载PDF
Determination of trans-resveratrol in mouse liver by high performance liquid chromatography
8
作者 姚倩 侯世祥 +3 位作者 何希辉 张瑄 颜军 苟小军 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第2期158-162,共5页
To develop a sensitive high performance liquid chromatography (HPLC) assay for the determination of trans-resveratrol in mouse liver. The whole liver of a mouse was removed from the body, homogenated, and extracted ... To develop a sensitive high performance liquid chromatography (HPLC) assay for the determination of trans-resveratrol in mouse liver. The whole liver of a mouse was removed from the body, homogenated, and extracted by ethyl acetate. The organic layer was isolated and evaporated to dryness, the residue was reconstituted in 0.2 mL mobile phase for centrifugation, and 50 uL of the supernatant was injected into the/-IPLC instrument. The sample was separated on a Shimadzu ODS column (150 mm × 4.6 mm, 5 um) at 35 ℃ and detected by ultraviolet (UV) detector at the wavelength of 305 nm. The mobile phase consisted of methanol and 0.1 mol/L acetic acid (4:6, v/v) with the flow-rote at 1 mL/min. The limit of detection was 3.0 ng/g in liver homogenate with a signal/noise ratio of 3:1. The linear range of the calibration curve was 5.0-120.0 ng/g. The mean recoveries at the concentrations of 6, 10 and 80 ng/g were 102%, 96.0% and 91.5%, respectively. The RSDs for inter- and intra-day assays were less than 5%. Compared with other reported methods, this method was faster and more sensitive. It was also proved to be of good linearity, selectivity, accuracy and precision, and can be efficiently applied to the pharmacoldnetic study of trans-resveratrol in mouse liver. 展开更多
关键词 high performance liquid chromatography TRANS-RESVERATROL Mouse liver
下载PDF
The New Type of Liquid Chromatography—Colloidal High-Performance Liquid Chromatography (CHPLC): Further Applications
9
作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2018年第4期51-56,共6页
The recent paper by I. Brondz (2018), “One-Step Procedure for Direct Purification of Pediocin-Like Bacteriocins and Cationic Antimicrobial Peptides from Complex Culture Medium on an Analytical, Semipreparative, and P... The recent paper by I. Brondz (2018), “One-Step Procedure for Direct Purification of Pediocin-Like Bacteriocins and Cationic Antimicrobial Peptides from Complex Culture Medium on an Analytical, Semipreparative, and Preparative Scale. A New Type of Liquid Chromatography—Colloidal High-Performance Liquid Chromatography (CHPLC)” (International Journal of Analytical Mass Spectrometry and Chromatography, 6, 41-49, https://doi.org/10.4236/ijamsc.2018.63004), described a new type of CHPLC. This technique allows colloidal liquids and suspensions to be chromatographed directly despite the presence in the liquids of material such as bacteria, fungi, and other soft and hard particles. The significance of this development lies in enabling the single-step cleanup and concentration of the target substance from a complex mixture of soluble molecules in the presence of insoluble particles by high performance liquid chromatography (HPLC). The technique also allows the use of viscose liquids (as described in Brondz (2018) that are not suitable for analysis by conventional HPLC. In the previous paper, emphasis was placed on describing the applications of the techniques for the preparation of target substances such as small peptides, bacteriocins, bacitracin, and lysosome. Normally, the industrial preparation of these substances requires multistep procedures, which are time- and labor-consuming, and typically results in significant loss of target material and specific activity. In the present paper, the application of CHPLC for the isolation of alkaloids from crude raw material such as opium cake is demonstrated. In the opium cake, large amounts of hard vegetable particles and even sand corns are present together with the target alkaloids. Despite this, isolation by CHPLC of the desired compound was achieved in a single step by using a water/ethanol-based liquid. Isolation of alkaloids from such raw material normally requires a multistep procedure that includes the preparation of insoluble tartrate or picrate complex and this process includes dissolving the substance in flammable organic liquid. The isolation described here was performed in a single step by using the water/ethanol-based liquid. 展开更多
关键词 COLLOIDAL high-performance liquid chromatography OPIUM CAKE ALKALOIDS MORPHINE
下载PDF
Novel method for the determination of five carbamate pesticides in water samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography 被引量:10
10
作者 Zhi Mei Liu Xiao Huan Zang Wei Hua Liu Chun Wang Zhi Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期213-216,共4页
A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) ... A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in water samples was developed by dispersive liquid-liquid microextraction (DLLME) coupled with high performance liquid chromatography-diode array detector (HPLC-DAD). Some experimental parameters that influence the extraction efficiency were studied and optimized to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 5 to 1000 ng mL^-1 for all the five carbamate pesticides, with the correlation coefficients (r^2) varying from 0.9984 to 0.9994. Good enrichment factors were achieved ranging from 80 to 177- fold, depending on the compound. The limits of detection (LODs) (S/N = 3) were ranged from 0.1 to 0.5 ng mL^-1. The method has been successfully applied to the analysis of the pesticide residues in environmental water samples. 展开更多
关键词 Carbamate pesticides high performance liquid chromatography Diode array detection Dispersive liquid-liquid microextraction Water samples
下载PDF
Comparison of protocatechuic aldchyde in Radix Salvia miitiorrhiza and corresponding pharmacological sera from normal and fibrotic rats by high performance liquid chromatography 被引量:6
11
作者 Tao Lv Xi-Xian Yao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第14期2195-2200,共6页
AIM: To observe the effect of protocatechuic aldchyde on the proliferation of hepatic stellate cells (HSCs). METHODS: Liver fibrosis was induced in rats by carbon tetrachloride (CCh). Then normal and fibrotic dr... AIM: To observe the effect of protocatechuic aldchyde on the proliferation of hepatic stellate cells (HSCs). METHODS: Liver fibrosis was induced in rats by carbon tetrachloride (CCh). Then normal and fibrotic drug sera were extracted from rats. The effects of protocatechuic aldchyde, raw Radix Salvia miltiorrhiza and drug sera of Salvia miltiorrhiza on HSC growth were determined by CCKoS. The protocatechuic aldchyde was separated by high performance liquid chromatography (HPLC) in a AIItima C18 column (250 mm × 4.6 mm, 5 μm) with a mobile phase of acetonitrile-4% glacial acetic acid solution (gradient elution) at the wavelength of 281 nm. RESULTS: Protocatechuic aldchyde, raw Radix Salvia miltiorrhiza and drug sera of Salvia miltiorrhiza were found to have inhibitory effects on proliferation of rat HSCs. Raw Radix Salvia miltiorrhiza had a stronger inhibitory effect than the drug sera. The fibrotic drug sera showed a higher suppressive effect than the normal drug sera (P 〈 0.05). Protocatechuic aldchyde was found in crude materials of both Radix Salvia miltiorrhiza and its corresponding drug sera. The average recovery (n = 6) was 110.5% for raw Salvia miltiorrhiza Bge, 102% for normal drug sera and 105.2% for fibrotic drug sera. The relative standard devitation (RSD) was 0.37%, 1.96% and 1.51%, respectively (n=6). The contents of protocatechuic aldchyde were 0.22%, 0.15% and 0.19%, respectively (n = 6) (P〈 0.05). The RSD was 0.33%, 0.75% and 1.24% (n=6) for raw material of Radix Salvia miltiorrhiza, normal drug sera and fibrotic drug sera, respectively. The samples were stable for 6 d. CONCLUSION: Protocatechuic aldchyde can inhibit the growth of HSCs. HPLC is suitable for the determination of virtual bioactive components of Chinese herbal medicines in vitro. 展开更多
关键词 Radix Salvia miltiorrhiza Protocatechuic aldchyde Seropharmacological method high performance liquid chromatography
下载PDF
Determination of the Flavonoids from Ginkgo Biloba Extract by High Performance Liquid Chromatography 被引量:3
12
作者 Li ZHANG Zhi Min XIANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第10期968-970,共3页
HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns. symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile ph... HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns. symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile phase, which can eliminate the time for cleaning the chromatographic system and simplify the analystic method for GBE Experimental conditions: column: Hypersil BDS C-18, 5mumx4x250 mm: column temperature: 35degreesC; mobile phase: 46% methanol-54% water; flow rate: 0.7 mL/min; detection wavelength: 360nm. 展开更多
关键词 Ginkgo biloba extract flavone glycoside high performance liquid chromatography.
下载PDF
Bio-analytical method development and validation of Rasagiline by high performance liquid chromatography tandem mass spectrometry detection and its application to pharmacokinetic study 被引量:2
13
作者 Ravi Kumar Konda Babu Rao Chandu +1 位作者 B.R.Challa Chandrasekhar B.Kothapalli 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第5期342-349,共8页
The most suitable bio-analytical method based on liquid liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard fo... The most suitable bio-analytical method based on liquid liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 (2.1 mm × 50 mm, 3.5 um) column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ionization mode using an API-4000 system. The lotal run time was 3.0 min. The proposed method has been validated with the linear range of 5 12000 pg/mL for Rasagiline. The intra-run and inter-run precision values were within 1.3% 2.9% and 1.6% 2.2% respectively for Rasagiline. The overall recovery for Rasagiline and Rasagiline-13C3 mesylate analog was 96.9% and 96.7% respectively. This validated method was successfully applied to the bioequivalence and pharmacokinetic study of human volunteers under fasting condition. 展开更多
关键词 high performance liquid chromatography Mass spectrometry RASAGILINE liquid-liquid extraction
下载PDF
Fingerprint analysis of placenta polypeptide injection by high performance liquid chromatography 被引量:2
14
作者 Li Huanga, Xiao-Man Wub, Yu Jib, Yu Wanga,baChina Pharmaceutical University, Nanjing 210009, China bJiangsu Institute for Food and Drug Control, Nanjing 210008, China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第1期71-75,共5页
Objective: To develop the representative fingerprint for the quality control of placenta polypeptide injection. Methods: The chromatographic separation was performed using a Phenomenex Gemini C18 column (250 mm 4.6 mm... Objective: To develop the representative fingerprint for the quality control of placenta polypeptide injection. Methods: The chromatographic separation was performed using a Phenomenex Gemini C18 column (250 mm 4.6 mm, 5 mm) maintained at 30 1C. 0.1% aqueous trifiuoroacetic acid (Solvent A) and acetonitrile contained 0.1% TFA (Solvent B) were used as mobile phase with a gradient elution. Detection wavelength was 280 nm with the sample injection volume of 50 mL; the fiow rate was 1.0 mL/min. The fingerprints of different samples were investigated by similarity analysis. Results: Nine peaks were identified as the characteristic common peaks. The similarities of the fingerprints of the 10 batches of samples were above 0.992. Conclusion: This method showed high precision and good repeatability, and provided the basis for the improvement of the quality control of placenta polypeptide injection. 展开更多
关键词 Placenta polypeptide injection FINGERPRINT Similarity analysis high performance liquid chromatography
下载PDF
Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography:Ⅱ.Influence of Several Testing Conditions 被引量:2
15
作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1999年第1期45-52,共8页
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
关键词 chromatographic conditions high performance liquid chromatography (hplc) organic acids root exudates
下载PDF
Determination of 17<i>α</i>-Methyltestosterone in Freshwater Samples of Tilapia Farming by High Performance Liquid Chromatography 被引量:3
16
作者 Isabel R. Barbosa Sara Lopes +3 位作者 Rhaul Oliveira Inês Domingues Amadeu M. V. M. Soares António J. A. Nogueira 《American Journal of Analytical Chemistry》 2013年第4期207-211,共5页
17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Ther... 17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Therefore methods need to be developed to detect residues of 17α-methyltestosterone in aqueous matrices. A simple high-performance liquid chromatographic method using ultraviolet detection (245 nm) and testosterone as internal standard has been developed for the monitoring 17α-methyltestosterone in freshwater samples of tilapia aquaculture. The method described involves limited sample preparation as it includes a filtration followed by a single solid-phase extraction step using C18 cartridge. Validation data indicated that the HPLC-UV method for 17α-methyltestosterone determination in the concentration range of 50 - 2000 μg/L provided good linearity, sensitivity, accuracy and precision. Method performance was efficiently applied to monitoring the freshwater samples of fish ponds and the surrounding aquatic channels. 展开更多
关键词 17α-Methyltestosterone high performance liquid chromatography Environment TILAPIA FARMING
下载PDF
On-line enrichment and determination of polycyclic aromatic hydrocarbons in atmospheric particulates using high performance liquid chromatography with fluorescence as detector 被引量:1
17
作者 HASHI Yuki WANG Tian-ran +1 位作者 LI Yue-qi LIN Jin-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第10期1261-1265,共5页
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
关键词 on-line enrichment on-line trap column high performance liquid chromatography hplc atmospheric particulate polycyclic aromatic hydrocarbons (PAHs)
下载PDF
Analysis of ganciclovir and its related substances using high performance liquid chromatography and liquid chromatography-mass spectrometry methods 被引量:1
18
作者 Cheng-Ping Li1,2,Mao Mao1,Lan-Jun Zheng1,Wei-Guang Shan11.College of Pharmaceutical Sciences,Zhejiang University of Technology,Hangzhou 310032 2.College of Biology and Environment Engineering,Zhejiang Shuren University,Hangzhou 310015,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2010年第4期218-222,共5页
Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 co... Objective High performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC/MS)methods were developed for the determination of ganciclovir and its related substances.Methods A Hypersil ODS2 column(4.6 mm×250 mm,5 μm)was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer(pH 6.0)-methanol(92∶8)at a flow rate of 1.0 mL/min,and UV detector set at 254 nm was used for monitoring the eluents.Results The method was simple,rapid,selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL.It has been validated with respect to accuracy,precision,linearity,and limits of detection and quantification.The linearity range was 10.2-153.0 μg/mL with r=0.9998.The percentage recoveries ranged from 96.7% to 101.6%,and RSD was 1.24%-1.96%(n=5).Conclusion The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir.For identification of related substances,LC/MS was used.The mainly related substances of ganciclovir active pharmaceutical ingredients(API)were determined as guanine,(1,3-dioxolan-4-yl)methyl acetate,and diacetyl guanine. 展开更多
关键词 GANCICLOVIR related substances high performance liquid chromatography high performance liquid chromatography/mass spectrometry
下载PDF
Development of the fingerprints for the quality evaluation of Viscum coloratum by high performance liquid chromatography 被引量:7
19
作者 Yun-Li Zhao Rong-Hua Fan +3 位作者 Hong-Xia Yuan Miao Yu Kai-Shun Bi Zhi-Guo Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第2期113-118,共6页
A high-performance liquid chromatography coupled ultraviolet (HPLC-UV) method was developed for a chemical fingerprint analysis of Viscum coloratura. Eighteen peaks were selected as the common peaks and Homoeriodict... A high-performance liquid chromatography coupled ultraviolet (HPLC-UV) method was developed for a chemical fingerprint analysis of Viscum coloratura. Eighteen peaks were selected as the common peaks and Homoeriodictyol-7-O-β-D-apiosiyl-(1→2)-β-D-glucoside was used as a reference. The relative areas of common peaks were used for hierarchical clustering analysis and similarity calculation. Thirty-seven samples collected from different sources were classified into five groups. The similarities of 21 batches Viscum coloratura samples were beyond 0.90. The results obtained suggest that the chromatographic fingerprint can efficiently identify Viscum coloratum. Additionally, the fingerprints can then be used to evaluate the correlation between Viscum coloratura and hosts. 展开更多
关键词 Viscum coloratum QUALITY high-performance liquid chromatography FINGERPRINT
下载PDF
Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction 被引量:1
20
作者 LI Cun-man XIAO Yuan-sheng +3 位作者 XUE Xing-ya FENG Jia-tao ZHANG Xiu-li LIANG Xin-miao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期392-396,共5页
An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matog... An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products. 展开更多
关键词 Unstable compound Isolation and purification Preparative high performance liquid chromatography Solid-phase extraction Iridoid glucoside
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部