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Overview of the Analytical Lifecycle of Supercritical Fluid Chromatography Methods
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作者 Bertyl Andri Amandine Dispas +1 位作者 Roland Djang’eing’a Marini Philippe Hubert 《American Journal of Analytical Chemistry》 2016年第1期75-91,共17页
In recent times, the overall interest over Supercritical Fluid Chromatography (SFC) is truly growing within various domains but especially for pharmaceutical analysis. However, in the best of our knowledge modern SFC ... In recent times, the overall interest over Supercritical Fluid Chromatography (SFC) is truly growing within various domains but especially for pharmaceutical analysis. However, in the best of our knowledge modern SFC is not yet applied for drug quality control in the daily routine framework. Among the numerous reported SFC methods, none of them could be found to fully satisfy to all steps of the analytical method lifecycle. Thereby, the present contribution aims to provide an overview of the current and past achievements related to SFC techniques, with a targeted attention to this lifecycle and its successive steps. The included discussions were therefore structured accordingly and emphasizing the analytical method lifecycle in accord with the International Conference on Harmonisation (ICH). Recent and important scientific outputs in the field of analytical SFC, as well as instrumental evolution, qualification strategies, method development methodologies and discussions on the topic of method validation are reviewed. 展开更多
关键词 Supercritical Fluid chromatography Ultra High Performance Supercritical Fluid chromatography Analytical method Lifecycle Quality by Design
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Preparation Process and Thin Layer Chromatography Identification of Wufang Babu Poultice
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作者 Junjun LIU Luyao XIE +2 位作者 Chuhui ZHOU Zhengteng YANG Xiongbin GUI 《Medicinal Plant》 CAS 2023年第4期58-61,共4页
[Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the prepar... [Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the preparation method of mixed pharmaceutical powder with suitable pharmaceutical excipients was adopted. Qualitative identification of medicinal materials in Wufang Babu Poultice (Strychni Semen, Rhei Radix Et Rhizoma, Dipsaci Radix, and Angelicae Sinensis Radix) was carried out by TLC. [Results] Mixed pharmaceutical powder mixed with glycerol, gelatin and other pharmaceutical excipients can be prepared for forming. The test solution chromatography of each medicinal material (Strychni Semen, Rhei Radix et Rhizoma, Dipsaci Radix, Angelicae Sinensis Radix) showed pigment spots of the same color at the same position as its corresponding control medicinal materials and reference chromatography, and the display was clear. [Conclusions] The preparation process is simple and feasible, and can be used as the forming process of Wufang Babu Poultice. The TLC determination method is simple to operate, has good specificity, and has no effect on negative results, and can be used for identification of Wufang Babu Poultice. 展开更多
关键词 Wufang Babu Poultice Preparation process Thin layer chromatography(TLC)
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Measuring methods for three kinds of polyhydroxyalkanoates from activated sludge by gas chromatography
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作者 陈玮 陈志强 +2 位作者 吕炳南 温沁雪 张运海 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第5期113-118,共6页
Gas chromatography determination of polyhydroxyalkanoates has been common;however,the pretreatment steps are often complex,and gas chromatography operation conditions are not given in detail.In this study,gas chromato... Gas chromatography determination of polyhydroxyalkanoates has been common;however,the pretreatment steps are often complex,and gas chromatography operation conditions are not given in detail.In this study,gas chromatography is used for analyzing PHB,PHV and PH2MV,three majors of PHAs in activated sludge.The sample was centrifuged at a speed of 4000 r/min for the separation of floc and supernatant,freezen,and dried for 12 h in vacuum freezing drier;and then transferred to the fridge for freezing to ice and drying for 12 h in vacuum freezing drier;then chloroform and a simple composition digestion solution including methanol,sulfuric acid and benzoic acid was added;digested at 105 ℃ for 6 h;cooled to room temperature,the lower solution of the result can be used for analyzing.Samples were analyzed by gas chromatography with FID detector and auto sampler;the standard curve of standard material shows an excellent linear relationship with correlation coefficients larger than 0.99;the relative standard deviation (RSD) of sludge samples is less than 1%.The recovery rates of each sample are between 95%-105%.The GC analysis time of each PHA sample is shorter than 10 minutes. 展开更多
关键词 POLYHYDROXYALKANOATES activated sludge gas chromatography measuring method
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ANALYSIS OF HUMAN PLACENTA BY ^(31)P NUCLEAR MAGNETIC RESONANCE AND THIN-LAYER CHROMATOGRAPHY SCANNING COMBINED WITH THE CORRECTIVE METHOD OF ABSORBANCE PROPORTIONAL COEFFICIENT
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作者 Rong GUO Jian wei CHEN Yi Min XU AiHua ZHANG Nanjing College of Traditional Chinese Medicine,Nanjing 210029 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1081-1084,共4页
Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance pr... Five phospholipids in human placenta were determined by phosphorus 31 nuclear magnetic resonance(^(31)P NMR)spectroscopy and thin-layer chromatography(TLC) scanning combined with the corrective method of absorbance proportional coefficient. The NMR spectrometer used this investigation was a Bruker AM-500 spectrometer operating at 202.4 MHz for ^(31)P chemical shifts are relative to 85% phosphoric acid. TIC was carried out by silica gel H plate developed in chloroform-methanol-glacial acetic acid-ethanol-water(25:4:6:2:0.5),with Vaskovsky reagent as colour -developing agent of phospholipids. 展开更多
关键词 P NUCLEAR MAGNETIC RESONANCE AND THIN-layer chromatography SCANNING COMBINED WITH THE CORRECTIVE method OF ABSORBANCE PROPORTIONAL COEFFICIENT ANALYSIS OF HUMAN PLACENTA BY LPC TLC
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Thin Layer Chromatography and Methodological Investigation of Matrine in Zhukuqin Granule
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作者 Wei WEI Wenjie ZHONG +1 位作者 Juan LIU Rongbin LING 《Medicinal Plant》 2017年第2期4-7,共4页
[Objectives] To establish a sensitive and simple thin layer chromatography method of matrine in Zhukuqin granule. [Methods]With Zhukuqin granule as control medicinal materials,matrine as reference substance,we chose o... [Objectives] To establish a sensitive and simple thin layer chromatography method of matrine in Zhukuqin granule. [Methods]With Zhukuqin granule as control medicinal materials,matrine as reference substance,we chose orthogonal test method,systematically investigated various factors affecting the thin layer chromatography,and selected the best thin layer chromatography conditions. [Results] We screened out the best thin layer chromatography of matrine in the Zhukuqin granule with chloroform as extraction solvent,solvent extraction and ultrasonic extraction as extraction method,toluene-acetone-ethyl acetate-ammonia solution( 2:3:4:0. 5) as developing agent,improvement of bismuth potassium iodide solution as color developing agent. [Conclusions] The separating degree of this method was high,it had good repeatability,and it could be used to control quality of Zhukuqin granule. 展开更多
关键词 Zhukuqin GRANULE MATRINE THIN layer chromatography
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Comparison of liquid-liquid extraction-thin layer chromatography with solid-phase extraction-high-performance thin layer chromatography in detection of urinary morphine 被引量:1
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作者 Ali Ahadi Alireza Partoazar +1 位作者 Mohammad Hassan Abedi Khorasgani Seyed Vahid Shetab Boushehri 《The Journal of Biomedical Research》 CAS 2011年第5期362-367,共6页
Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tr... Liquid-liquid extraction-thin layer chromatography (LLE-TLC) has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction (SPE) is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography (HPTLC) has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, 'were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories. 展开更多
关键词 morphine detection liquid-liquid extraction thin-layer chromatography solid-phase extraction highperformance thin layer chromatography
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Secondary metabolite credentials ofEvolvulus alsinoides by high performance thin layer chromatography(HPTLC) 被引量:2
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作者 Duraisamy Gomathi Manokaran Kalaiselvi +3 位作者 Ganesan Ravikumar Dominic Sophia Velliyur Kanniappan Gopalakrishnan Chandrasekar Uma 《The Journal of Biomedical Research》 CAS 2012年第4期295-302,共8页
Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance... Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance thin layer chromatography(HPTLC) finger printing of the ethanolic extract of Evolvulus alsinoides.Phytochemical screening was done by standard procedures and HPTLC method was also established to analyze alkaloids,flavonoids and phenolic compounds from the ethanolic extract of Evolvulus alsinoides.Preliminary phytochemical screening showed that ethanol extracted more secondary metabolites than other solvents.HPTLC fingerprinting analysis showed the presence of various alkaloids,flavonoids and phenols(quercetin) in the ethanolic extract.It can be concluded that Evolvulus alsinoides may serve as a source of potent antioxidants that may be used in the prevention of various diseases such as cancer,diabetes and cardiovascular diseases due to the presence of phenolic compounds.HPTLC finger print of Evolvulus alsinoides may be useful in the differentiation of the species from adulterants and act as a biochemical marker for this medicinally important plant in the pharmaceutical industry and plant systematic studies. 展开更多
关键词 Evolvulus alsinoides high performance thin layer chromatography(HPTLC) secondary metabolites CONVOLVULACEAE
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Determination of Fructose and Glucose Contents in Honey by Liquid Chromatography-refractive Index Detection Method and Direct Titration Method 被引量:1
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作者 Xiaoya PU Xusheng DU +1 位作者 Bo LIU Hua ZHANG 《Agricultural Biotechnology》 CAS 2016年第2期31-33,共3页
In this study, fructose and glucose contents in honey were determined by liquid chromatography-refractive index detection method and alkaline copper tartrate solution-direct titration method. According to the results,... In this study, fructose and glucose contents in honey were determined by liquid chromatography-refractive index detection method and alkaline copper tartrate solution-direct titration method. According to the results, there were great differences between determination results of reducing sugar contents by liquid chromatography-refractive index detection method and alkaline copper tartrate solution-direct titration method. Specifically, average determination results of reducing sugar contents by liquid chromatography-refractive index detection method were reduced by about 9.5% compared with alkaline copper tartrate solution-direct titra- tion method. Subsequently, determination results of reducing sugar contents by two methods were compared and analyzed. Liquid chromatography-refractive index detection method was used to determine fructose and glucose monomers in honey, but alkaline copper tartrate solution-direct titration method was used to determine reducing sugar composition in honey, which might lead to significantly different results. Due to small sample size and limited conditions, the determination results were not necessarily representative. Bee product acquisition and processing enterprises and relevant departments should pay much attention on these issues and fully consider the current situation of grass-roots units to develop scientific, rigorous, simple, universal, convenient, low-cost and practicable standards, thus ensuring the safety and reliability of food quality. 展开更多
关键词 HONEY FRUCTOSE GLUCOSE Liquid chromatography with refractive index detection method
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Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata(Haw.)using high performance thin layer chromatography 被引量:1
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作者 Nishi Srivastava Sharad Srivastava +2 位作者 Shikhar Verma Ajay Kumar Singh Rawat Abdul Rahman Khan 《The Journal of Biomedical Research》 CAS 2014年第4期328-331,共4页
Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distribut... Dear Editor: Therapeutically active metabolite contents in a med- icinal plant vary in nature, which may impact on its therapeutic efficacy. Bergenia (Saxifragaceae) is an evergreen perennial herb widely distributed in Central and East Asia with about 30 species reported worldwide. It grows at a range of altitudes from the Khasia hills at 400 feet to the temperate Himalayas from Kashmir to Bhutan at 7,000-10,000 feet. Its distribution over a wide range of altitudinal zones makes it a good candidate for studying variations in its metabolic profiles under different climatic conditions. Bergenin (C-glycoside of 4-O-methyl gallic acid) has been identified as a potent active secondary metabolite in Bergenia and other therapeutically active constituents including, among others, gallic acid (3,4,5 trihydroxybenzoic acid), (+) catechin, and gallicin (Fig. 1). 展开更多
关键词 HPTLC using high performance thin layer chromatography Evaluation of quantitative variation of secondary metabolites in Bergenia ciliata Haw HIGH
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Study of Cuscuta chinensis Lam. in Nuhuang Fuzheng Oral Liquid by Thin Layer Chromatography
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作者 Wengui FU Zhiqiang YAN +3 位作者 Shaoqin ZHAI Maixun ZHU Hua ZHENG Xingzhong SUN 《Medicinal Plant》 CAS 2017年第5期6-10,共5页
[Objectives] To better control the quality of Nuhuang Fuzheng Oral Liquid and study the main component Cuscuta chinensis Lam.by Thin Layer Chromatography. [Methods] Through changing the treatment methods of the test s... [Objectives] To better control the quality of Nuhuang Fuzheng Oral Liquid and study the main component Cuscuta chinensis Lam.by Thin Layer Chromatography. [Methods] Through changing the treatment methods of the test sample solution,proportion of the developing solvent and sample application volume,taking the spot resolution,definition,and Rf value,optimal Thin Layer Chromatography conditions were screened for Cuscuta chinensis Lam. [Results] After the test sample solution passing the neutral alumina column,it was extracted two times using the ethyl acetate. Methanol was added to dissolve. Benzene-ethyl acetate-formic acid( 5∶5∶2.5) was used as developing solvent.And ammonia fumigation was carried out to develop color. In the thin layer chromatograph obtained through these conditions,Nuhuang Fuzheng Oral Liquid test sample solution showed the same stripe in the same position of the control drug chromatogram and there was no obvious tailing phenomenon and the spot was clear. [Conclusions] The thin layer chromatography identification conditions can be used as the method for quality control of Cuscuta chinensis Lam. in Nuhuang Fuzheng Oral Liquid. 展开更多
关键词 Nuhuang Fuzheng Oral Liquid Identification by thin layer chromatography CUSCUTA CHINENSIS LAM Quality control
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Application of Thin Layer Chromatography in Preparation of Drug Containing Serum of Eucalyptus Oil
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作者 Bingyang GUO Yongli YU +2 位作者 Shijuan LUO Xiaoqing YIN Mingzhen XU 《Medicinal Plant》 CAS 2018年第1期19-24,共6页
[Objectives] To explore whether the thin layer chromatography( TLC) can be used to guide the preparation of drug containing serum of eucalyptus oil. [Methods]Eucalyptus oil samples with different dilution ratio were d... [Objectives] To explore whether the thin layer chromatography( TLC) can be used to guide the preparation of drug containing serum of eucalyptus oil. [Methods]Eucalyptus oil samples with different dilution ratio were detected by TLC. Eucalyptus oil was intragastrically administered to mice,serum samples of different eucalyptus oil doses,different intragastric administration methods and different blood sampling times were collected. The above samples were detected by TLC,and the above results were verified by gas chromatography. [Results] TLC can detect concentration difference of eucalyptus oil samples with different dilution ratio. TLC can provide qualitative and semi-quantitative detection of eucalyptus oil in serum. High,medium and low dose of eucalyptus oil in serum had different effects on the growth of MCF-7 cells in the SD rats( P < 0. 05). [Conclusions] TLC can be used to guide the preparation of drug containing serum of eucalyptus oil. 展开更多
关键词 Chinese medicine drug containing serum Eucalyptus oil Thin layer chromatography
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DETERMINING THE CONTENT OF JASMINODIN IN MEI RONG CAPSULE WITH THIN LAYER CHROMATOGRAPHY
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作者 慕慧 李林 +2 位作者 周玲 王晓利 胡森科 《Academic Journal of Xi'an Jiaotong University》 2001年第1期81-82,共2页
Objective Jasminodin in Mei Rong capsule was determined by the method or thin layer chromatog- raphy. Mothods The sample Jasminodin was extracted with methanol and then the extract was chromatographed on silica gel GF... Objective Jasminodin in Mei Rong capsule was determined by the method or thin layer chromatog- raphy. Mothods The sample Jasminodin was extracted with methanol and then the extract was chromatographed on silica gel GF254 plate with chloroform-methanol-water(10:3:1) as mobile phase and the chromatograms were scanned by using Shimadzu CS-930 dual wavelength TLCS in zegzag scanning mode at λ_s 370nm and λR 250nm. Results Callbration graph was rectilinear between 2.7μg^16.2μg per spot for the jasminodin. Conclusion Satisfa- tory results were obtained with the average recovery ratio of 99.76%,RSD 2.27%. 展开更多
关键词 jasminodin thin layer chromatography Mei Rong capsule
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Method for the Determination of Sudan Dyes in Foods-High Performance Liquid Chromatography Jointly Issued by AQSIQ and SAC 被引量:1
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《China Standardization》 2005年第3期8-,共1页
Sudan Red are the chemosynthesis dyes of series of azo, which are mainly used as coloring additives in ma- nufacturing of some products, such as the wax, the oil-dyes, the petrol, and etc. In the process of food produ... Sudan Red are the chemosynthesis dyes of series of azo, which are mainly used as coloring additives in ma- nufacturing of some products, such as the wax, the oil-dyes, the petrol, and etc. In the process of food production, Sudan Dyes are banned to be used as food dyes in our country. 展开更多
关键词 method for the Determination of Sudan Dyes in Foods-High Performance Liquid chromatography Jointly Issued by AQSIQ and SAC
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Identification of Ethnic Medicine Polygonum capitatum by Thin Layer Chromatography
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作者 Haicheng WEN Yongjing SU +2 位作者 Huagang LIU Wei WEI Songji WEI 《Medicinal Plant》 CAS 2022年第2期16-17,共2页
[Objectives]To establish a thin-layer chromatography identification method for the ethnic medicinal materials of Polygonum capitatum.[Methods]The thin layer chromatography(TLC)method was used to identify materials.[Re... [Objectives]To establish a thin-layer chromatography identification method for the ethnic medicinal materials of Polygonum capitatum.[Methods]The thin layer chromatography(TLC)method was used to identify materials.[Results]The TLC identification showed that in the chromatogram of the test sample,there were spots of the same color in the corresponding position of the chromatogram of the reference medicinal material,and the reproducibility was good.[Conclusions]The TLC identification and the determination results of the inspection items can provide a basis for the quality control of the medicinal materials of P.capitatum. 展开更多
关键词 Ethnic medicine Polygonum capitatum Thin layer chromatography(TLC) Quality control
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Identification of Citric Acid in Wuhuang Oral Liquid by Thin Layer Chromatography
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作者 Zhiqiang YAN Guowen CAO +2 位作者 Shaoqin ZHAI Maixun ZHU Hua ZHENG 《Medicinal Plant》 2017年第3期43-46,共4页
[Objectives] To screen the identification conditions of citric acid in Wuhuang Oral Liquid by thin layer chromatography,and establish the quality control method for citric acid in Wuhuang Oral Liquid.[Methods] Differe... [Objectives] To screen the identification conditions of citric acid in Wuhuang Oral Liquid by thin layer chromatography,and establish the quality control method for citric acid in Wuhuang Oral Liquid.[Methods] Different treatment methods were adopted for test sample,developing agent,and drying time,thin layer chromatography separation condition and spot definition were taken as indicators to conduct experiment,to select optimal thin layer identification method. [Results] Methanol was used as the extraction solvent,ultrasonic treatment,ether extraction,dissolution by anhydrous ethanol as treatment conditions of test sample; upper solution of butyl acetate-formic acid-water(4 ∶ 2 ∶ 2) after placing one hour was taken as developing agent; 0. 1% bromocresol green(BCG) as the developer; when developing the color in 3 hours after development,in thin layer chromatograph,there appeared the same strip in the same position of test sample of Wuhuang ORAL Liquid and control substance,no obvious trailing phenomenon,and the color was uniform and clear.[Conclusions]The thin layer chromatography identification conditions can be used as the method for quality control of Wuhuang Oral Liquid. 展开更多
关键词 Wuhuang ORAL LIQUID IDENTIFICATION by THIN layer chromatography Quality control
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Thin Layer Chromatography Screening for Glycyrrhiza uralensis
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作者 Lijing CAO Lihua YUAN Kaiyan LIAO 《Medicinal Plant》 2017年第4期32-36,共5页
[Objectives] To establish a simple and rapid,specific and reproducible thin layer chromatography( TLC) method,and accordingly establish a thin layer identification method for quality control of Glycyrrhiza uralensis. ... [Objectives] To establish a simple and rapid,specific and reproducible thin layer chromatography( TLC) method,and accordingly establish a thin layer identification method for quality control of Glycyrrhiza uralensis. [Methods] According to the physical and chemical properties,components of Glycyrrhiza uralensis were identified by thin layer chromatography. According to Veterinary Pharmacopoeia of the People's Republic of China 2010( Volume Ⅱ) and related literature report,the thin layer chromatography identification method was studied and improved for Glycyrrhiza uralensis.[Results] When the preparation method for test sample solution was 6g Glycyrrhiza uralensis added with 30 mL saturated n-butanol,ultrasonic processing 20 min,filtered,filtrate dried,added 3 mL methanol and obtained Glycyrrhiza uralensis test sample solution. Then,chloroform-methanol-formic acid-ethyl acetate( 10∶ 3∶ 2∶ 3) as developing solvent,clear spot with high degree of separation and reproducibility could be obtained,and can be used for thin layer chromatography identification of ammonium glycyrrhetate in Glycyrrhiza uralensis.[Conclusions] The modified method omitted the step of ether treatment of samples,and directly adopted saturated n-butanol to extract components. It does not influence the detection of chromatographic spots,and solves the issue of sample gelatinizing sticking and filtration,simplifies the test process,and reduces the harm to human body. 展开更多
关键词 GLYCYRRHIZA uralensis SEPARATION effect THIN layer chromatography identification Developing SOLVENT
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Quality Evaluation of Leontopodium franchetii Beauv. from Different Localities Based on Moisture,Ash and Extract Contents and Thin-layer Chromatography
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作者 Pei QUN Yatao HAN +3 位作者 Fang XIAO Zhe LIU Yongxia KE Yuan LIU 《Medicinal Plant》 CAS 2018年第4期56-58,共3页
[Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L... [Objectives] The aim was to determine the moisture,ash and extract contents in Leontopodium franchetii Beauv. from different localities. [Methods] The contents of moisture,total ash,acid-insoluble ash and extract in L. franchetii from different localities were determined according to the methods described in Chinese Pharmacopoeia( 2015 Edition). [Results] In the 10 samples,the contents of moisture were all less than or equal to 15. 0%; the contents of total ash were all below 12. 0%; and the contents of acid-insoluble ash were all less than 3. 0%. The contents of water-soluble extract( by cold-soaked extraction method) in the samples were all below 12. 0% except those from Hongyuan Prairie of Sichuan Province and Xinglong Mountain in Lanzhou City,Gansu Province. [Conclusions]The contents of the four indicators measured in this experiment varied by small margins,indicating that the quality was relatively stable. This study provides theoretical data for the revision of the quality standards for L. franchetii. 展开更多
关键词 Leontopodium franchetii Beauv. MOISTURE ASH Extract Content Thin-layer chromatography Quality evaluation
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Separation of Amino Acids Based on Thin-Layer Chromatography by a Novel Quinazoline Based Anti-Microbial Agent
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作者 Supriti Sen Sandipan Sarkar +1 位作者 Pijush Kundu Subrata Laskar 《American Journal of Analytical Chemistry》 2012年第9期669-674,共6页
A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography pl... A newly designed quinazoline based compound, 6-pyridin-2-yl-5,6-dihydro-benzo[4,5]imidazo[1,2-c] quinazoline (PDBIQ) has shown the ability for the easy detection of nineteen amino acids on thin-layer chromatography plates as a spray reagent. This new reagent enabled to produce various distinguishable colors with amino acids with different RF values. The detection limits and the binding ability of PDBIQ with amino acids have been calculated. PDBIQ is also able to detect aminoacids from hydrolised seed protein. The title compound also exhibited profound inhibitory action against some gm (+ve) and gm (-ve) bacterial organisms. This paper deals with synthesis, spectroscopic application and biological evaluation of the organic moity. 展开更多
关键词 THIN-layer chromatography Amino Acid NINHYDRIN Binding Constant ANTIMICROBIAL Property
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Novelties Filtration Theory of Liquid Chromatography-Mass Spectrometry in Volume Nanotube of Cotton Filament of Layers Woven Fabrics
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作者 ElSayed A. ElNashar 《Journal of Textile Science and Technology》 2021年第1期14-21,共8页
Objectives of the research to present a modern theory of water purification for multiple purposes entitled “a novelties filtration theory of liquid chromatography-mass spectrometry” is an exceedingly sensitive and s... Objectives of the research to present a modern theory of water purification for multiple purposes entitled “a novelties filtration theory of liquid chromatography-mass spectrometry” is an exceedingly sensitive and specific analytical technique in volume layers woven fabrics that can precisely determine the identities and quantities of compounds within volume Nanotube of cotton filament of layers woven fabrics. The problems are that the filters in the local and international markets have increased complications in configuration, installation and cost without reaching the efficiency that humanity hopes. Throw materials and methods the chromatography-mass spectrometry in layers woven fabrics, and throw the nanotube of cotton filament for purification of water dyes and smells. Industry, in which mass spectrometry is a convenient, versatile method for characterization and identification of process throw the Nanotube of cotton filament for purification of water dyes and smells. Results came up with a theme “innovations in textiles”, and also, for characterization of fibers and contaminants of the fabrics. Additive manufacturing in layers woven fabrics, are the processes used to synthesize a volume object under computer control with successive material layers that have been used and highlighted. The conclusions has included chromatography-mass spectrometry drop, physico-chemical, biological, combined physical-biological and chemical-biological treatment processes recently being developed to meet Jet-filtration, the strict discharging limits set by ASTM standards. Some important aspects of both qualitative and quantitative data analysis have been described and the power of using mass profiles to enhance selectivity and sensitivity has been demonstrated. 展开更多
关键词 Filtration Theory Liquid chromatography-Mass SPECTROMETRY layerS Woven Fabrics
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Gas Chromatographic Method for Identification and Quantification of Commonly Used Residual Solvents in Pharmaceuticals Products
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作者 Sreekanta Nath Dalal Pranab Kumar Das 《American Journal of Analytical Chemistry》 CAS 2024年第8期241-252,共12页
Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three dif... Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three different types of impurities are generally available in the pharmaceutical’s product specification: organic impurities, inorganic impurities, and residual solvents. Residual solvents are organic volatile chemicals used or generated during the manufacturing of drug substances or drug products. Purpose: The aim of this study is to develop a cost-effective gas chromatographic method for the identification and quantification of some commonly used solvents—methanol, acetone, isopropyl alcohol (IPA), methylene chloride, ethyl acetate, tetrahydrofuran (THF), benzene, toluene, and pyridine—in pharmaceutical product manufacturing. This method will be able to identify and quantify the multiple solvents within a single gas chromatographic procedure. Method: A gas chromatography (GC) equipped with a headspace sampler and a flame ionization detector, and a column DB 624, 30-meter-long × 0.32-millimeter internal diameter, 1,8 μm-thick, Brand-Agilent was used to develop this method. The initial GC oven temperature was 40°C and held for 5 minutes. It was then increase to 80˚C at a rate of 2˚C per minute, followed by a further increase to 225˚C at a rate of 30˚C per minute, with a final hold at 225˚C for 10 minutes. Nitrogen was used as a carrier gas at a flow rate of 1.20 mL per minute. Dimethyl sulfoxide (DMSO) was selected as sample solvent. Results: The developed method is precise and specific. The percent RSD for the areas of six replicate injections of this gas chromatographic method was within 10.0 and the recovery result found within 80.0% to 120.0%. 展开更多
关键词 method Development Gas chromatography Compendial method GDP SPECIFICITY RECOVERY
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