ANALYSIS OF HUMAN PLACENTA BY ^(31)P NUCLEAR MAGNETIC RESONANCE AND THIN-LAYER CHROMATOGRAPHY SCANNING COMBINED WITH THE CORRECTIVE METHOD OF ABSORBANCE PROPORTIONAL COEFFICIENT

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.

Quality Evaluation of Leontopodium franchetii Beauv. from Different Localities Based on Moisture,Ash and Extract Contents and Thin-layer Chromatography

[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.

Separation of Amino Acids Based on Thin-Layer Chromatography by a Novel Quinazoline Based Anti-Microbial Agent

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.

Simple and Rapid Thin-layer Chromatography Method for Quantitative Measurement of Free Cholesterol in Serum

ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused. The solvent System was petroleum ether-ethyl acetate-glacial acetic acid (8o:20:1) and the spra-ying reagent was a solution of sulphuric acid and vanillin. Under the selected con-ditions, the peak area was linearly related to the cholesterol amount for the range between 80～700 ng per spot. The intraplate and interplate coefficients were 2.4% and 7.4% respectively. The recovery of cholesterol was 101.6%. The method presented was simple, rapid and accurate. The results of experi-mental investigation and clinical application were satisfactory.

Analysis of the Nucleoside Content of Cordyceps sinensis Using the Stepwise Gradient Elution Technique of Thin-Layer Chromatography

Nucleoside is the main class of active components in Cordyceps sinensis. Thin-layer chromatography (TLC) is one of the most commonly used methods in pharmacopoeias for analyzing chemical components of herbal medicine. Since the isocratic elution method cannot be applied successfully in TLC analysis for separating all the nucleoside components, the stepwise gradient elution has been developed in this work to separate eight nucleoside standards with success. In this way, quantitative analyses of the samples of Cordyceps sinensis were achieved via the pro-posed TLC procedure coupled with the scanning densitometric techniques of CAMAG and TLCQA methods for qualitative and quantitative analysis.

Simple and robust differentiation of Ganoderma species by high performance thin-layer chromatography coupled with single quadrupole mass spectrometry QDa

In this study,a high performance thin-layer chromatography/single quadrupole mass spectrometry QDa(HPTLC-QDa)method for robust authentication of Ganoderma lucidum,a popular and valuable herbal medicine,has been developed.This method is simple and practical,which allows direct generation of characteristic mass spectra from the HPTLC plates automatically with the application of in situ solvent desorption interface.The HPTLC silica gel plates were developed with toluene-ethyl formate-formic acid(5:5:0.2,V/V)and all bands were transferred to QDa system directly in situ using 80%methanol with 0.1%formic acid as desorption solvent.The acquired HPTLC-QDa spectra showed that luminous yellow band b3,containing ganoderic acid B/G/H and ganodeneric acid B,the major active components of Ganoderma,could be found only in G.lucidum and G.lucidum(Antler-shaped),but not in G.sinense and G.applanatum.Moreover,bands b13 and b14 with m/z 475/477 and m/z 475/491/495,respectively,could be detected in G.lucidum(Antler-shaped),but not in G.lucidum,thus allowing simple and robust authentication of G.lucidum with confused species.This method is proved to be simple,practical and reproducible,which can be extended to analyze other herbal medicines.

Differentiation of Belamcandae Rhizoma and Iridis Tectori Rhizoma by Thin-Layer Chromatography and High-Performance Liquid Chromatography

Objective:Belamcandae Rhizoma and Iridis Tectori Rhizoma are easily confused with each other.The main objective of this study is to distinguish them using chemical analysis.Materials and Methods:Thin-layer chromatography(TLC)and high-performance liquid chromatography(HPLC)fingerprint methods were established to compare the chemical profile,while HPLC quantitation was used to determine the contents of three isoflavones in thirty batches of Belamcandae Rhizoma and Iridis Tectori Rhizoma samples.Results:The two herbs could be distinguished by TLC using acetic acid-n hexane-ethyl acetate(1:90:80 v/v/v)as the mobile phase,according to the fluorescent band under 366 nm at R_(f) 0.2.In total,12 compounds were identified in the 24-min HPLC fingerprint.The similarity coefficient between the two herbs was 0.54±0.01.Mangiferin(1),tectoridin(2),iridin(3),irigenin(5),irisflorentin(6),and iristectorin A(9)were the main peaks in Belamcandae Rhizoma,while tectoridin(2)and tectorigenin(4)were the major peaks in Iridis Tectori Rhizoma.The contents of 2 in Iridis Tectori Rhizoma(2.50±0.20%)were 8.93 times higher than that of Belamcandae Rhizoma(0.28±0.08%),while the ones of 5 and 6 were slightly lower in Iridis Tectori Rhizoma.Conclusions:The study established fast and effective methods to distinguish Belamcandae Rhizoma from Iridis Tectori Rhizoma.

Simultaneous qualitative identification of all medicinal herbs in Zaoren Anshen capsule by thin-layer chromatography

The holistic characterization and quality control of all the medicinal herbs of proprietary Chinese medicines(PCMs)are of great significance to ensure their safety,efficacy,and consistency.Thin-layer chromatography(TLC),a simple and classic approach for qualitatively characterizing and examining quality markers of natural products,has been widely used in the characterization and quality control of traditional Chinese medicines.Zaoren Anshen(ZRAS)capsule,prepared from three medicinal herbs of fried Ziziphi Spinosae Semen,Salvia Miltiorrhiza Radix et Rhizoma,and vinegar-processed Schisandrae Chinensis Fructus,is a famous PCM in China for the treatment of insomnia,amnesia,and dizziness in clinical practice.However,no effective method is available so far for simultaneous identification and examination of all the three medicinal herbs of ZRAS capsule.In the present study,we developed a TLC method via twice-development and visualization by UV light or chromogenic agent,which could be used for simultaneous qualitative identification of all the three medicinal herbs of ZRAS capsule in one plate.Moreover,the sample preparation method was optimized.The developed TLC method was rapid,simple,low-cost,and effective,and thus it could be used for quality control of ZRAS capsule.

Characteristics and main controlling factors of intra-platform shoal thin-layer dolomite reservoirs:A case study of Middle Permian Qixia Formation in Gaoshiti-Moxi area of Sichuan Basin,SW China

Based on the study of the distribution of intra-platform shoals and the characteristics of dolomite reservoirs in the Middle Permian Qixia Formation in the Gaoshiti–Moxi area of the Sichuan Basin,SW China,the controlling factors of reservoir development were analyzed,and the formation model of“intra-platform shoal thin-layer dolomite reservoir”was established.The Qixia Formation is a regressive cycle from bottom to top,in which the first member(Qi1 Member)develops low-energy open sea microfacies,and the second member(Qi2 Member)evolves into intra-platform shoal and inter-shoal sea with decreases in sea level.The intra-platform shoal is mainly distributed near the top of two secondary shallowing cycles of the Qi2 Member.The most important reservoir rock of the Qixia Formation is thin-layer fractured-vuggy dolomite,followed by vuggy dolomite.The semi-filled saddle dolomite is common in fracture-vug,and intercrystalline pores and residual dissolution pores combined with fractures to form the effective pore-fracture network.Based on the coupling analysis of sedimentary and diagenesis characteristics,the reservoir formation model of“pre-depositional micro-paleogeomorphology controlling shoal,sedimentary shoal controlling dolomite,penecontemporaneous dolomite benefiting preservation of pores,and late hydrothermal action effectively improving reservoir quality”was systematically established.The“first-order high zone”micro-paleogeomorphology before the deposition of the Qixia Formation controlled the development of large area of intra-platform shoals in Gaoshiti area during the deposition of the Qi2 Member.Shoal facies is the basic condition of early dolomitization,and the distribution range of intra-platform shoal and dolomite reservoir is highly consistent.The grain limestone of shoal facies is transformed by two stages of dolomitization.The penecontemporaneous dolomitization is conducive to the preservation of primary pores and secondary dissolved pores.The burial hydrothermal fluid enters the early dolomite body along the fractures associated with the Emeishan basalt event,makes it recrystallized into medium–coarse crystal dolomite.With the intercrystalline pores and the residual vugs after the hydrothermal dissolution along the fractures,the high-quality intra-platform shoal-type thin-layer dolomite reservoirs are formed.The establishment of this reservoir formation model can provide important theoretical support for the sustainable development of Permian gas reservoirs in the Sichuan Basin.

Stability indicating high performance thin-layer chromatographic method for simultaneous estimation of pantoprazole sodium and itopride hydrochloride in combined dosage form

A specific, precise and stability indicating high-performance thin-layer chromatographic method for simultaneous estimation of pantoprazole sodium and itopride hydrochloride in pharmaceutical formulations was developed and validated. The method employed TLC aluminium plates precoated with silica gel 60F254 as the stationary phase. The solvent system consisted of methanol：water：ammonium acetate; 4.0：1.0：0.5 （v/v/v）. This system was found to give compact and dense spots for both itopride hydrochloride （Rf value of 0.55__＋0.02） and pantoprazole sodium （Rf value of 0.85＋0.04）. Densitometric analysis of both drugs was carried out in the reflectance- absorbance mode at 289 nm. The linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9988___0.0012 in the concentration range of 100--400 ng for pantoprazole sodium. Also, the linear regression analysis data for the calibration plots showed a good linear relationship with R2=0.9990_＋0.0008 in the concentration range of 200-1200 ng for itopride hydrochloride. The method was validated for specificity, precision, robustness and recovery. Statistical analysis proves that the method is repeatable and selective for the estimation of both the said drugs. As the method could effectively separate the drug from its degradation products, it can be employed as a stability indicating method.

Thin-Layer Chromatographic Separation of Amino Acid Enantiomers using Ligand Exchange

Silica gel thin-layer plates covered with L-arginine and copper acetate were used for the separation of amino acid enantiomers, The chromatographic selectivity and the effects of plate different preparation methods, sample molecular structure and solvent compositions on resolution performance were also discussed.

ANALYSIS OF STRYCHNINE ALKALOIDS IN BIOLOGICAL SAMPLES BY THIN-LAYER CHROMATOGRAPHIC DENSITOMETRY AND DISTRIBUTION STUDY OF STRYCHNINE IN INTOXICATED RATS

A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer chromatograpic scanner in zig-zag dual-wavelength reflection mode.Detection sensitivity for strychniue was about 0. 05 μg. Quantification recoveries were between89. 2% and 99. 5% with RSD between 2. 92% and 13. 21 %. The method was applied to investigate thedistribution or strychnine in intoxicated rats. The results showed that there were remarkable difference in organs or tissues with the aigaest concentration 4. 56±1. 41μg/g in liver. Diversification experiment proves the method also could be used to analyze other alkaloids in biological samples if theconditions slightly modified.

A review of SAGD technology development and its possible application potential on thin-layer super-heavy oil reservoirs

Super-heavy oil is a significant unconventional energy source,and more than 30 years of research have shown that steam-assisted gravity drainage(SAGD)technology is suitable for thick super-heavy oil reservoirs.Recently,more and more thin-layer super-heavy oil reservoirs have been discovered in China,while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply,so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil.To this end,this paper focuses on the enlightenment of field application in SAGD technology.Firstly,based on typical SAGD field projects,the development history of SAGD technology in the world was reviewed,and the influence of reservoir physical properties on the application of SAGD technology in thin-layer superheavy oil reservoirs was analyzed.Secondly,the well pattern,wellbore structure,pre-heating,artificial lift,and monitor technique of SAGD were detailed described,and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs.Lastly,the gas-and solventassistant SAGD were comprehensively evaluated,and their application potential in thin-layer superheavy oil reservoirs was studied.The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.

Study on microwave-induced thin-layer drying of municipal sludge for fuel reclamation

Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying is considered, which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism bears great meaning for its development and utilization. The effects of temperature and microwave cracking in municipal sewage sludge drying characteristics are stud- ied through municipal sewage sludge drying experiment. Experiments shows that higher drying temperature would lead to a more acutely changing drying rate （DR）. The DR had increased from 0.005 g/（g.min） to 0.060 g/（g·min）, which was 12 times enlarged, while the temperature rose from 70℃ to 160 ℃. The higher the temperature was, the earlier the peak value of DR appeared. The experiments indicated that the temperature was the decisive factor affecting the DR. The microwave-induced sludge reached the highest DR at the moisture rate （MR） of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the DR was rising in proportion to the microwave radiation dose. The diffusion coefficient had been calculated according to Fick＇s law. In com- parison to that of the original one, the diffusion coefficient of microwave-induced sludge was obviously enlarged more than two times. By fit examinations, Model Weibull was proven to be the most fit one for thermal thin-layer drying of municipal sludge. By means of Arrhenius equation, the obtained average activation energy of municipal sludge was 37.1 kJ/（mol·K）.

Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I. Development and Assessment of Chromatographic Conditions *1

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.

APPLICATIONS AND MANUFACTURE OF THE MICROSCALE LONG-OPTICAL-PATH ELECTROCHEMICAL CELL WITH A PLUG-IN THIN-LAYER ELECTRODE

The construction and characteristics of a microscale long-optical-path electrochemi- cal cell with a plug-in thin-layer electrode are described.Using ferricyanide as the test species,the thermodynamic parameters of electron transfer processes are determined at car- bon,plantinum,and gold electrodes.

A Reflectance Thin-layer Spectro-electrochemical Method

IntroduCtion Speetroeleetroehemieal measurement 15 simultaneously to determine theeleetroehemieal and speetral

Immunocytochemical examination of PTEN and Ki-67 for endometrial carcinoma using thin-layer endometrial preparations

The current study is designed to evaluate certain immunocytochemical(ICC)biomarkers to gain a better cytodiagnosis.For this purpose,85 patients from March 2016 to March 2019 who planned to get a hysteroscopy assay were recruited.Cytological sampling was conducted by scratching the uterus cavity using SAP-1,and the samples were processed as liquid-based smears,using SurePath technology.36 patients diagnosed with EC or atypical endometrial hyperplasia were recruited in this study.33 cases were diagnosed with EC,and 3 cases were diagnosed with atypical endometrial hyperplasia,allocated with EC or precancerous lesions group.26 cases were diagnosed with benign lesions group.Among these cases,9 cases were diagnosed with endometrial simple hyperplasia,2 cases were diagnosed with complicated hyperplasia,5 cases were diagnosed with an irregular proliferation of endometrium and 10 cases were diagnosed with endometrial polyps.There were 23 cases in the healthy group.Staining in thin-layer endometrial preparations by ICC and using H-score or counting the percentage of stained cells.The presentation of PTEN in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 50(Youden’s index:0.698)PTEN expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 83.7%and 86.1%.The presentation of Ki-67 in normal endometrium,benign lesions,and EC/precancerous lesions were different(p<0.01).Taking the cut-off value of 15%(Youden’s index:0.76)Ki-67 expression for the diagnosis of EC/precancerous lesion,the sensitivity and specificity were 94.4%and 81.6%.In this study,the use of different cut-off values for Ki-67 and PTEN helped differentiate endometrial lesions.Immunocytochemistry in the ECT detection of PTEN and Ki-67 can improve the diagnostic capabilities of endometrial cancer and precancerous lesions.

Photothermal-photocatalytic thin-layer flow system for synergistic treatment of wastewater

The integration of the photocatalytic effect into solar steam is highly desirable for addressing freshwater shortages and water pollution.Here,a ternary film structure for the adsorption and photothermal and photocatalytic treatment of wastewater was designed by combining the technique of self-assembled carbon nano paper with a nitrogen composite titanium dioxide(N-TiO_(2))deposited on the surface of carbon nanotubes(CNT)using polyvinylidene fluoride(PVDF)as a substrate.The photogeneration of reactive oxygen species can be promoted by rapid oxygen diffusion at the three-phase interface,whereas the interfacial photothermal effect promotes subsequent free radical reactions for the degradation of rhodamine B(93%).The freshwater evaporation rate is 1.35 kg·m^(-2)·h^(-1)and the solar-to-water evaporation efficiency is 94%.Importantly,the N-TiO_(2)/CNT/PVDF(N-TCP)film not only effectively resists mechanical damage from the environment and maintains structural integrity,but can also be made into a large film for outdoor experiments in a large solar energy conversion device to collect fresh water from polluted water and degrade organic dyes in source water simultaneously,opening the way for applications in energy conversion and storage.

An electromagnetic wave attenuation superposition structure for thin-layer plasma

This work proposes a new plasma super-phase gradient metasurfaces(PS-PGMs)structure,owing to the limitations of the thin-layer plasma for electromagnetic wave attenuation.Based on the cross-shaped surface unit configuration,we have designed the X-band absorbing structure through the dispersion control method.By setting up the Drude dispersion model in the computer simulation technology,the designed phase gradient metasurfaces structure is superposed over the plasma,and the PS-PGMs structure is constructed.The electromagnetic scattering characteristics of the new structure have been simulated,and the reflectance measurement has been carried out to verify the absorbing effect.The results demonstrate that the attenuation effect of the new structure is superior to that of the pure plasma structure,which invokes an improved attenuation effect from the thin layer plasma,thus enhancing the feasibility of applying the plasma stealth technology to the local stealth of the strong scattering part of a combat aircraft.