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Objective To determine the monosaccharide composition of polysaccharides in different Cordyceps powder preparations by capillary zone electrophoresis (CZE). Methods The orthogonal experiment was used to optimize the total degradation conditions of the extracted polysaccharides; The monosaccharide composition was determined by CZE method using 1-phenyl-3-methyl-5-pyrazolone (PMP) as a derivatizing reagent. The electrophoresis conditions were as follows: uncoated fused silica capillary column (70 cm × 50 μm i.d., effective length was 61 cm); 40 mmol/L borax solution (pH 10.1) was used as the running buffer; The detection wavelength was set at 245 nm; The operation voltage was 13 kV; Hydrodynamic pressure injection was employed (10 cm × 8 s). Results The optimum hydrolysis conditions were as follows: 1.0 mol/L sulfuric acid solution, hydrolysis temperature 100 ℃, and hydrolysis time 5 h. The common monosaccharides of polysaccharides in Xinganbao Capsule, Bailing Capsule, Zhiling Junsi Capsule, and Jinshuibao Capsule were xylose, glucose, mannose, and galactose, but the content was different. The monosaccharide components contained in the polysaccharides of the four preparations were basically the same as those of the Cordyceps sinensis, and monosaccharides included xylose, rhamnose and glucuronic acid which were not reported in Cordyceps sinensis were detected. Each monosaccharide had a good linear relationship with the concentration range of 0.01 to 0.20 mg/mL, the limits of detection (LOD, S/N = 3) and the limits of quantification (LOQ, S/N = 10) ranged from 0.205 to 0.397 μg/mL and 0.684 to 1.323 μg/mL, respectively. RSDs of the precision test were 0.8%-3.6%, RSDs of the repeatability test were 2.7%-4.7%, and 2.8%-4.7% in the stability test. The recovery rate of the method showed that the mean recoveries of glucose and galactose ranged from 96.1% to 99.8% and 95.1% to 99.6% respectively, and RSD values fell within 1.0%-2.0% and 1.5%-1.9%, respectively. Conclusion The method is fast and efficient, and provides a reference for the improvement of quality standard of Cordyceps powder preparations and the intensive study on the substitution of Cordyceps powder for Cordyceps sinensis.
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OBJECTIVE: To establish a capillary zone electrophoresis(CZE) -based method for charge heterogeneity analysis of IgG2 monoclonal antibody. METHODS: The concentrations of TETA and EACA, pH of separation buffer and temperature of capillary were optimized, to obtain a method which can efficiently separate the charge variants of IgG2 mabs. The reproducibility and repeatability of the optimized CZE method were validated and a battery of mabs were evaluated. RESULTS: The separation effect was significantly influenced by TETA/EACA concentration, pH and separation temperature. Through a series of optimization, a CZE method which showed good resolution and precision(RSD of area percentage was below 3.0% was established and the method parameters were as below: 400 mmol•L-1 EACA/0.05% TETA, pH 6.2, separation under 30 kV voltage at 35℃. This method was also suitable for IgG1 and IgG4 mabscharge heterogeneity analysis. Based on the specific electrophorogram and migration time, it could also be used as an identification method for monoclonal antibodies. CONCLUSION: The optimized CZE method can efficiently separate the charge variants of IgG2 mabs and shows good precision and specificity, which can be used to analyze the charge heterogeneity and identification of monoclonal antibodies.
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CC chemokine receptor 4 (CCR4) is a kind of G-protein-coupled receptor, which plays a pivotal role in allergic inflammation. The interaction between 2-(2-(4-chloro-phenyl)-5-{[(naphthalen-1-ylmethyl)-carbamoyl]-methyl}-4-oxo-thiazolidin-3-yl)-N-(3-morpholin-4-yl-propyl)-acetamide (S009) and the N-terminal extracellular tail (ML40) of CCR4 has been validated to be high affinity by capillary zone electrophoresis (CZE). The S009 is a known CCR4 antagonist. Now, a series of new thiourea derivatives have been synthesized. Compared with positive control S009, they were screened using ML40 as target by CZE to find some new drugs for allergic inflammation diseases. The synthesized compounds XJH-5, XJH-4, XJH-17 and XJH-1 displayed the interaction with ML40, but XJH-9, XJH-10, XJH-11, XJH-12, XJH-13, XJH-14, XJH-3, XJH-8, XJH-6, XJH-7, XJH-15, XJH-16 and XJH-2 did not bind to ML40.Both qualification and quantification characterizations of the binding were determined. The affinity of the four compounds was valued by the binding constant, which was similar with the results of chemotactic experiments. The established CEZ method is capable of sensitive and fast screening for a series of lactam analogs in the drug discovery for allergic inflammation diseases.
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FASS(field amplified sample stacking) is a technique for on-column enrichment in capillary zone electrophoresis. The distribution of solute in column during injection can be divided into two parts: the stack zone in running buffer and the sample solution zone imported by electroosmosis. Based on the investigation of transfer of solute in column, the results showed that the relationship between the length of two zone and injection time was nonlinear, so the relationship of injecting size that related with the mobility of solute and injection time. The increasing of the enrichment effect will not synchronize with the increasing of injection size, and the enrichment effect is decreased due to the laminar flow. To hold a basic constant column efficiency and desire enrichment effect, the ratio of mobility of solute in two zones should be maximum, and the injection time should also match with the ratio.
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Capillary zone electrophoresis (CZE) was developed to investigate the structure stability of novel camptothecin derivative (L-P) at different pH,the kinetics and thermodynamics of hydrolysis reaction from lactone form to carboxylate form direction at near physiological conditions (pH 7.4,310 K). Uncoated fused-silica capillaries(35 cm×50 μm i. d,with effective length of 26.5 cm) were used. The background electro-lyte( BGE) was 0.025 mol/L sodium phosphate buffer with pH varied at 2.5,4.0,5.0,6.0,7.0,7.4 and 9. 0. The electrophoresis voltage was maintained at 14 kV when the pH of BGE ranged between 2.5 and 5.0,otherwise,the voltage was maintained at 10 kV. The UV detector was set at 260 nm. All samples were introduced using hydrodynamic injection at 5 kPa for 4 s. L-P was found to be lactone form as the solution pH was below 4. 0. As pH increased,the lactone form of L-P would undergo hydrolysis reaction to be carboxylate form. As pH was 9.0,L-P existed almost completely as carboxylate form. The rate constant of the hydrolysis increased as temperature raise. The energy of activation ( Ea) ,the enthalpy ( ΔH) and entropy (ΔS) of the hydrolysis reaction were determined as 72. 6 kJ/mol,10. 5 kJ/mol and 50. 9 J/( mol K) ,respectively. The proposed capillary zone electrophoresis could efficiently separate two pH-dependent structural forms of the novel camptothecin derivative( L-P). The positive enthalpy and entropy values of the L-P hydrolysis indicated that the reaction was endothermic and entropically driven and higher temperature favored.
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OBJECTIVE:To establish a high performenc capillary zone electrophoresis method for the determination of the water-soluble active ingredients in different parts of the Salvia miltiorrhiza.METHODS:Capillary electrophoresis was conducted using uncoated capillary column(75 ?m?50.2 cm,effective length=40 cm)with 5 mmol?L-1 phosphate-borax(ph7.4)as running buffer by pressure injection(0.5 psi/4 s)and constant voltage separation(20 kV)with a detection length of 210 nm and a column temperature of 25 ℃.RESULTS:A complete baseline separation of PAH,DSS and PA was achieved within 8 min under the optimized conditions.The good linear range was from 2.5 ?g?mL-1 to 200.0 ?g?mL-1 for all the three ingredients.The average recoveries of the 3 ingredients were 100.04%,99.99%,and 100.01%,respectively,with RSD at 1.75%,1.73%,and 1.74%,respectively.CONCLUSION:The method is satisfactory in precision,recovery and linearity,and it can be used to determine three water-soluble active ingredients in different parts of the Salvia miltiorrhiza.
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OBJECTIVE:To establish a method for the determination of Oleanolic acid and Ursolic acid isomers in Hedyotis corymbosa.METHODS: Capillary zone electrophoresis with high frequency conductivity detection was adopted.The separation of sample was performed on an uncoated fused silica capillary(55 cm?75 ?m ID) at an effective length of 50 cm.1.2 mmol?L-1 Triethylamine(TEA)-HCl(pH10.0) buffer containing 0.24 mmol?L-1 ?-cyclodextrin was selected for the running buffer solution.The voltage applied was 12.5 kV and the sample was injected by gravity for 10 s at a height of 20 cm.Brufen was used as internal standard.RESULTS: The linear ranges for Oleanolic acid and Ursolic acid were 3.9～39.0 ?g?mL-1(r=0.999 1) and 20.0～140.0 ?g?mL-1(r=0.999 0),respectively,and their average recovery rates were 96.5% and 96.0% respectively and RSD were 1.98% and 1.09%,respectively(n=6).CONCLUSION:It was proved that the method was simple,accurate,rapid and reproducible,and applicable for the quality control of Hedyotis corymbosa.
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OBJECTIVE:To develop a method for separating the cefuroxime enantiomers by capillary zone electrophoresis(CZE).METHODS:Melting capillary column(570mm?75?m)was used with0.04mmol/L hydroxypropyl-?-cyclodextrin and37.5mmol/L NaH 2 PO 4 as buffer solution(pH=6.0).The operation voltage was15kV;temperature was25℃;detecting wavelength was280nm and pressure injection was performed at5kPa for6seconds.RESULTS:The total time for separation and determination was within10min.The recovery was90%～106%.CONCLUSION:This method is simple and rapid,and can be used to determine the content of cefuroxime enantiomers in cefuroxime powder for injection.
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5.5 the separation was not achieved.The compound of cyclodextrin and terbutaline increased with the increase of cyclodextrin when the volume rate of cyclodextrin was 0.4% 1.6%,making terbutaline easier for separation.Conclusion:The types of ? CD,the concentration and pH of buffer are the major factors influencing the separation of terbutaline and it can be completely separated.
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To study a method for determination of sulfamethoxazole, sulfadiazine and trimethoprim tablets, a compound tablet of sulfamethoxazole, sulfadiazine and trimethoprim. METHOD: A capillary zone electrophoresis (CZE) method was used to assay three components of this compound preparation. RESULTS: The complete separation of components was achieved with 0.05 molL-1 pH 6.0 running phosphate buffer and a constant voltage of 20 kV (current of 95 μA～105 μA). The retention times of individual components were between three and eight minutes and a good linearity was shown between concentration and peak area in the concentration range over 70 μgml-1～750 μgml-1. When acetanilide was used as internal standard, the relative standard deviation (RSD) of each component determined in a batch was less than 1% (n=9). The recovery of each component was not less than 96.45% with RSD less than 3%. The analytical results obtained from 6 samples of clinical use were inconsistent with those by standard method, however the quantity of each sulfa drug was obtained by CZE method. CONCLUSION: The results showed this method is accurate, simple, and rapid. When this method is used, the quantity of each three components is determined, but by the standard method, only the total quantity of the two sulfa drugs is obtained.
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Object To preliminarily study the difference of proteins in the seed of spine date and the seed of Indian jujube. Methods Protein contents were measured with Kieldahl method. Amino acids constituting the protein were determined by means of acidolysis. The proteins were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and capillary zone electrophoresis (CZE). Results Contents of proteins in the seed of spine date and the seed of Indian jujube were 36.13% and 41.58%, respectively. The content of valine and methionine in the seed of Indian jujube were significantly more than that in the seed of spine date remarkably, and the contents of other amino acids from the seed of spine date and seed of Indian jujube were similar. Their SDS-PAGE spectra showed that the seed of spine date contained a protein with molecular weight 39 800 and the seed of Indian jujube contained a protein with molecular weight 50 100 . In CZE spectra for the seed of spine date, there was a peak at the mobile time of 3.1 min and in CZE spectra from the seed of Indian jujube, there was a peak at the mobile time of 4.8 min. Conclusion Protein content in the seed of Indian jujube is more than that in the seed of spine date; The content of valine and methionine in the seed of Indian jujube is more than that in the seed of spine date remarkably. The spectra of SDS-PAGE and CZE for the seed of spine date are different from that for the seed of Indian jujube clearly.
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AIM:Capillary electrophoresis fingerprints(CEFP) and quantitative analysis methods of Radix Scutellariae were established. METHODS:All experiments were carried out in an uncoated fused silica capillary(75 cm?75 ?m i.d.,effective length 63 cm) with a 50 mmol/L sodium borate solution(contained 5% acetonitrile,pH 9.30) under 12 kV while the detection wavelength was set at 280 nm and naproxen was selected as the internal standard. RESULTS:8 co-possessing peaks were selected in the CEFP taking naproxen referential peak.The similarities between each of the ten places and the referential CEFP of Radix Scutellariae were evaluated both the qualitative similarity S_F and the quantitative similariy Q,the apparent quantitative similarity R. CONCLUSION:The method of the CEFP and quantitative analysis are rapid,simple and accurate with a good repeatability and can be used for the quality control of Radix Scutellariae.
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AIM:To develop a new method to determine cucurbitacin B in Pedicellus Melo by capillary zone(electrophoresis(CZE).) METHODS:All the samples were analysed on a fused silica capillary(75 cm?75 ?m I.D.) by using 50 mmol/L sodium borate solution(containing 5% acetonitrile) as the background electrolyte with the running voltage at 12.0 kV and detection wavelength of 265 nm.And clorprenaline hydrochloride was applied as the internal standard. RESULTS:The results showed a good linear correlation between relative peak area of cucurbitacin B(y) and its concentration(x) over the range of 0.15～1.2 mg/mL.Regression equation was y=(0.003 4x)+0.058,r=0.999 7,and the average recovery for baicalin was 100.2% with the RSD at(2.11%). CONCLUSION:The method is rapid,simple,reproducible and produces low pollution.It serves as a novel way to determine cucurbitacin B.
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AIM: To investigate the method for using semi-bionic extraction (SBE) on Simiao Yongan Decoction as an example. METHODS: Orthogonal design was used to optimize the extraction conditions of SBE with the evaluation markers such as chlorogenic acid, ferulic acid, glycyrrhizic acid, total polysaccharide, ethanol soluble extractives and dried extract. RESULTS: The optimized SBE conditions were as follows: The medical material was powdered through a sieve with 4 meshes) and extracted with 20% ethanol for three times, the pH of the three extractions were in proper order 3.50, 7.50, 8.50 ; the solvent volume was 10,8,8 times, respectively, and the extraction time was 1.5,1.0,1.0 h, respectively. CONCLUSION: The optimum extraction conditions are stable and practicable, and surpass the original SBE extraction conditions.
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Objective: To establish the analytical method for the characteristic electropherograms of PSP by High Performance Capillary Electrophoresis(Capillary Zone Electrophoresis). Method: Types, concentration and pH of electrolyte, voltage, temperature, length and size of column were investigated for the analysis of PSP and BSA which is as standard using capillary zone electrophoresis. Results: The optimum condition is that 10mmol?L -1 boric acid buffer, pH9.18, a column 50?m?57cm(HP, effective length of 48.5cm), 30KV, temperature 25 ?C ,DAD detection. The analysis is ended within 7min. Conclusion: The method is simple, rapid and reliable. The characteristic electropherograms of PSP can be established.