With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral sele...With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral selector concentrations were optimized; and the effect of organic modifier on separation of chlorpheniramine enantiomers was also inver展开更多
The genus Armeniaca Scop. is well known for its popular cultivated edible fruit trees such as Armeniaca vul- garis Lam. and ornamental flowers such as A. mume Sieb. Another species, A. cathayana Fu et al., one of six ...The genus Armeniaca Scop. is well known for its popular cultivated edible fruit trees such as Armeniaca vul- garis Lam. and ornamental flowers such as A. mume Sieb. Another species, A. cathayana Fu et al., one of six important dry fruits （kernel-using apricot）, is cultivated for its edible seeds in North China. In the present study, DNA from 70 individuals of A rmeniaca, including 38 of A. cathayana, 18 ofA. vulgaris, 12 ofA. sibirica, 1 ofA. dasycarpa and 1 of A. mume, was extracted and analyzed using microsatellites and capillary electrophoresis. For 20 polymorphic loci selected, 339 alleles and 140.7 effective alleles were detected. The number of alleles per locus ranged from 8 to 28, with an average of 16.95 alleles per locus. The observed heterozygosity （Ho） and the expected heterozygosity （He） ranged from 0.427 to 0.971 and from 0.737 to 0.912, respectively. The polymorphism information content varied from 0.708 to0.905, with an average of 0.827. Based on the genetic similarity among 70 individuals, a UPGMA was used to establish the phylogenetic relationships. The taxonomic positions among five species were clearly revealed, and A. cathayana was more closely related to A. vulgaris than to A. sibirica. The results will provide a scientific basis for research on the taxonomy, germplasm resources and breeding ofArmeniaca, especially for A. cathayana.展开更多
A peptides migration model based on the principle of mechanics is presented in capillary zone electrophoresis (CZE). It is shown that the migration that the (tr) is a function of electric (Q), relative molecular mass ...A peptides migration model based on the principle of mechanics is presented in capillary zone electrophoresis (CZE). It is shown that the migration that the (tr) is a function of electric (Q), relative molecular mass (Mr), conformation parameter (Rc) of peptides and electrophoretic condition parameter(A). The conformation parameter is introduced to characterize multifarious shapes owing to the complex conlormation and the various kinds of macromolecules, where Rc≥1/3. The parameters A and Rc can be obtained from experimental data. The times of migration of the nine standard peptides were measured in pH 2.5buffer on different electrophoretic conditions in CZE. The experimental results agreed well with the theoretical prediction.展开更多
Capillary zone electrophoresis has been applied to the analysis of nucleotides. The effects of buffer concentration. pH and other operating conditions on the separation were investigated and optimized. By using the me...Capillary zone electrophoresis has been applied to the analysis of nucleotides. The effects of buffer concentration. pH and other operating conditions on the separation were investigated and optimized. By using the method, separation and identification of nuclotides in swine tissues were completed.展开更多
Aim To study the chiral separation of chlorpheniramine(Chp) by using a mixture of β CD and glutamate β CD as the chiral additive in CE. Methods Mixture of β cyclodextrin and glutamate β cyc...Aim To study the chiral separation of chlorpheniramine(Chp) by using a mixture of β CD and glutamate β CD as the chiral additive in CE. Methods Mixture of β cyclodextrin and glutamate β cyclodextrin was used as a chiral selector to the separation of chlorpheniramine. The effects of the concentrations of β cyclodextrin and glutamate β cyclodextrin, the voltage and the pH of buffers on the separation of chlorpheniramine were studied. Results The chiral recognization of the mixed chiral selector was better than that of a single selector. At pH below 4, the pH of buffers did not affect the separation and the separation of chlorpheniramine had good reproducibility. Conclusion Using a mixture of β CD and Glu β CD as chiral selector is useful for the enantioseparation of Chp in CE.展开更多
Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affini...Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affinity CE) with some proteins and by cyclodextrin electrokinetic chromatography (CDEKC) with some charged cyclodextrins (CDs). Many successful enantiomer separations are demonstrated from our study in this review article. In the enantiomer separations by affinity CE, the deterioration of detection sensitivity was observed under high concentration of the protein in running solutions. The partial filling technique was practically useful to solve the serious problem. It allowed operation at high protein concentrations, such as 500 μmol/L, without the detection problem. Charged CDs had several advantages for the enantiomer separations over neutral ones. Strong electrostatic interactions between a charged CD and oppositely charged analytes should be effective for the formation of the complex. A large difference in electrophoretic mobility between the free analyte and the inclusion complex should also enhance the enantiomeric resolution. In CE mass spectrometry (CE MS), the partial filling technique was applied to avoid the introduction of nonvolatile chiral selectors into the CE MS interface. By replacing the nonvolatile electrolytes in the running buffer by volatile ones, the separation conditions employed in CE with the UV detection method could be transferred to CE MS.展开更多
Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy)...Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy) propyl]}-β-cyclodextrin (i.e. L-Val-β-CD), heptakis{2,6-di-O-[3-L-(1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Phe-β-CD), heptakis{2,6-di-O-[3-(D, L-1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. D,L-Phe-β-CD), heptakis{2,6-di-O-[3-(L-1-hydroxymethyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Ser-β-CD), heptakis{2,6-di-O-[3-(L-1-carboxylmethyl carboxyl methyl amino)- 2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Asp-β-CD), heptakis{2,6-di-O-[3-(L-2-carboxyl tetramethylene amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Pro-β-CD). Their chemical structures were certified using FTIR and ()~1H NMR. Except for L-Phe-β-CD and D,L-Phe-β-CD, that are in soluble in water, the other amino acid derived β-CDs all have good water solubility. D,L-tyrosine and promethazine were baselinely separated by L-Val-β-CD in capillary electrophoresis.展开更多
This work presents an approach to build a high-performance, low-viscous and replaceable separation matrix, semi-crosslinked polyacrylamide （semi-CPA） capillary gel electrophoresis. Non- denatured basic proteins, suc...This work presents an approach to build a high-performance, low-viscous and replaceable separation matrix, semi-crosslinked polyacrylamide （semi-CPA） capillary gel electrophoresis. Non- denatured basic proteins, such as lysozyme, cytochrome C, ribonuclease A and trypsin were separa- ted. The impacts of monomer and cross-linker concentrations on protein separation were studied, and the ability of dynamic capillary inner wall coating was demonstrated. The UV absorption interfer- ence by semi-CPA gel matrix was successfully overcome by a partial filling technique, which results in sensitivity 20 times higher than other protein separation method. The excellent separation ability, reproducibility and dynamic coating ability made semi-CPA an ideal separation media in both capillar- y electrophoresis and microfluidic chip separation scheme.展开更多
Microchip capillary electrophoresis （MCE） has significant impact on diagnostic testing. One of the most importance in clinical analysis test is the determination of cholesterol level in blood, because its increase i...Microchip capillary electrophoresis （MCE） has significant impact on diagnostic testing. One of the most importance in clinical analysis test is the determination of cholesterol level in blood, because its increase is associated with coronary heart disease which is a major cause of death world over. Polydimethylsiloxane （PDMS） was material used to make a MCE for determination of cholesterol. Hydrogen peroxide was generated from the oxidation of cholesterol with cholesterol oxidase （ChOx） and was detected electrochemically at a downstream gold （Au） wire electrode by amperometry. Various parameters, such as the detection potential, concentration of running buffer, pH of running buffer, separation voltage, injection time, and concentration of ChOx, were studied. The migration time of cholesterol is less than 100s and the calibration curve is linear from 50 mg.dL-1 to 250 mg-dL-1 with the coefficient of determination （R2） of 0.9955. Therefore, this proposed assay is very rapid and sensitive for the detection of cholesterol.展开更多
Fused-silica capillaries used in capillary zone electrophoresis were statically coated with γ- glycidoxypropyltrimethoxysilane and epoxy polymer in order to suppress wall adsorption in the separation of proteins. It ...Fused-silica capillaries used in capillary zone electrophoresis were statically coated with γ- glycidoxypropyltrimethoxysilane and epoxy polymer in order to suppress wall adsorption in the separation of proteins. It has been shown that a significant decrease in adsorption was obtained and eletroosmotic flow was the diminished in the pH range 3-5. However with higher pH values, appreciable peak deformation and decreases in the resolving power were observed. Under pH 5, the epoxy polymer coating was shown to be quite stable and exhibited reproducible separations from run-to-run and day-to-day over a period of time.展开更多
The samples of licorice (Glycyrrhiza uralensis Fisch.) from 14 different cultivated areas were determined by the method of high Performance Capillary Electrophoresis (HPCE) for the contents of glycyrrihizic acid (GA) ...The samples of licorice (Glycyrrhiza uralensis Fisch.) from 14 different cultivated areas were determined by the method of high Performance Capillary Electrophoresis (HPCE) for the contents of glycyrrihizic acid (GA) in root. The results showed that the licorice plants come from various cultivated areas of China has different contents of GA. The GA content of licorice from Zhaodong in Heilongjiang Province is the highest, followed by those from E抰uoke, Chifeng, and Hangjin Banner in Inner Mongolia. Some suggestions for establishing the production base of licorice were put forward based on the study.展开更多
文摘With high performance capillary electrophoresis using -cyclodextrin or its deriveatives as the chiral selectors, five pairs of drug enantiomers were separated, The PH of the back- gmund electrolyte and the chiral selector concentrations were optimized; and the effect of organic modifier on separation of chlorpheniramine enantiomers was also inver
基金financially supported by 948 Project(No.2011-4-37)Standardization Project(No.2013-LY-082) of The State Forestry Administration of China
文摘The genus Armeniaca Scop. is well known for its popular cultivated edible fruit trees such as Armeniaca vul- garis Lam. and ornamental flowers such as A. mume Sieb. Another species, A. cathayana Fu et al., one of six important dry fruits （kernel-using apricot）, is cultivated for its edible seeds in North China. In the present study, DNA from 70 individuals of A rmeniaca, including 38 of A. cathayana, 18 ofA. vulgaris, 12 ofA. sibirica, 1 ofA. dasycarpa and 1 of A. mume, was extracted and analyzed using microsatellites and capillary electrophoresis. For 20 polymorphic loci selected, 339 alleles and 140.7 effective alleles were detected. The number of alleles per locus ranged from 8 to 28, with an average of 16.95 alleles per locus. The observed heterozygosity （Ho） and the expected heterozygosity （He） ranged from 0.427 to 0.971 and from 0.737 to 0.912, respectively. The polymorphism information content varied from 0.708 to0.905, with an average of 0.827. Based on the genetic similarity among 70 individuals, a UPGMA was used to establish the phylogenetic relationships. The taxonomic positions among five species were clearly revealed, and A. cathayana was more closely related to A. vulgaris than to A. sibirica. The results will provide a scientific basis for research on the taxonomy, germplasm resources and breeding ofArmeniaca, especially for A. cathayana.
文摘A peptides migration model based on the principle of mechanics is presented in capillary zone electrophoresis (CZE). It is shown that the migration that the (tr) is a function of electric (Q), relative molecular mass (Mr), conformation parameter (Rc) of peptides and electrophoretic condition parameter(A). The conformation parameter is introduced to characterize multifarious shapes owing to the complex conlormation and the various kinds of macromolecules, where Rc≥1/3. The parameters A and Rc can be obtained from experimental data. The times of migration of the nine standard peptides were measured in pH 2.5buffer on different electrophoretic conditions in CZE. The experimental results agreed well with the theoretical prediction.
文摘Capillary zone electrophoresis has been applied to the analysis of nucleotides. The effects of buffer concentration. pH and other operating conditions on the separation were investigated and optimized. By using the method, separation and identification of nuclotides in swine tissues were completed.
文摘Aim To study the chiral separation of chlorpheniramine(Chp) by using a mixture of β CD and glutamate β CD as the chiral additive in CE. Methods Mixture of β cyclodextrin and glutamate β cyclodextrin was used as a chiral selector to the separation of chlorpheniramine. The effects of the concentrations of β cyclodextrin and glutamate β cyclodextrin, the voltage and the pH of buffers on the separation of chlorpheniramine were studied. Results The chiral recognization of the mixed chiral selector was better than that of a single selector. At pH below 4, the pH of buffers did not affect the separation and the separation of chlorpheniramine had good reproducibility. Conclusion Using a mixture of β CD and Glu β CD as chiral selector is useful for the enantioseparation of Chp in CE.
文摘Capillary electrophoresis (CE) has become a powerful tool for enantiomer separations during the last decade. Since 1993, the author has investigated enantiomer separations by affinity capillary electrophoresis (affinity CE) with some proteins and by cyclodextrin electrokinetic chromatography (CDEKC) with some charged cyclodextrins (CDs). Many successful enantiomer separations are demonstrated from our study in this review article. In the enantiomer separations by affinity CE, the deterioration of detection sensitivity was observed under high concentration of the protein in running solutions. The partial filling technique was practically useful to solve the serious problem. It allowed operation at high protein concentrations, such as 500 μmol/L, without the detection problem. Charged CDs had several advantages for the enantiomer separations over neutral ones. Strong electrostatic interactions between a charged CD and oppositely charged analytes should be effective for the formation of the complex. A large difference in electrophoretic mobility between the free analyte and the inclusion complex should also enhance the enantiomeric resolution. In CE mass spectrometry (CE MS), the partial filling technique was applied to avoid the introduction of nonvolatile chiral selectors into the CE MS interface. By replacing the nonvolatile electrolytes in the running buffer by volatile ones, the separation conditions employed in CE with the UV detection method could be transferred to CE MS.
文摘Six new kinds of amino acid derived β-cyclodextrins were synthesized to improve their water solubility and chiral separation properties. They are heptakis{2,6-di-O-[3-L-(1-isopropyl carboxyl methyl amino)-2-(hydroxy) propyl]}-β-cyclodextrin (i.e. L-Val-β-CD), heptakis{2,6-di-O-[3-L-(1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Phe-β-CD), heptakis{2,6-di-O-[3-(D, L-1-benzyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. D,L-Phe-β-CD), heptakis{2,6-di-O-[3-(L-1-hydroxymethyl carboxyl methyl amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Ser-β-CD), heptakis{2,6-di-O-[3-(L-1-carboxylmethyl carboxyl methyl amino)- 2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Asp-β-CD), heptakis{2,6-di-O-[3-(L-2-carboxyl tetramethylene amino)-2-hydroxy propyl]}-β-cyclodextrin (i.e. L-Pro-β-CD). Their chemical structures were certified using FTIR and ()~1H NMR. Except for L-Phe-β-CD and D,L-Phe-β-CD, that are in soluble in water, the other amino acid derived β-CDs all have good water solubility. D,L-tyrosine and promethazine were baselinely separated by L-Val-β-CD in capillary electrophoresis.
基金Supported by the Key Project in the National Science ＆ Tech- nology Pillar Program During the Eleventh Five-Year Plan Pe- riod （2009BAK59B02）
文摘This work presents an approach to build a high-performance, low-viscous and replaceable separation matrix, semi-crosslinked polyacrylamide （semi-CPA） capillary gel electrophoresis. Non- denatured basic proteins, such as lysozyme, cytochrome C, ribonuclease A and trypsin were separa- ted. The impacts of monomer and cross-linker concentrations on protein separation were studied, and the ability of dynamic capillary inner wall coating was demonstrated. The UV absorption interfer- ence by semi-CPA gel matrix was successfully overcome by a partial filling technique, which results in sensitivity 20 times higher than other protein separation method. The excellent separation ability, reproducibility and dynamic coating ability made semi-CPA an ideal separation media in both capillar- y electrophoresis and microfluidic chip separation scheme.
基金supported by National Center of Excellence for Petroleum,Petrochemicals,and Advanced Materials,and the CU Graduate School Thesis Grant
文摘Microchip capillary electrophoresis （MCE） has significant impact on diagnostic testing. One of the most importance in clinical analysis test is the determination of cholesterol level in blood, because its increase is associated with coronary heart disease which is a major cause of death world over. Polydimethylsiloxane （PDMS） was material used to make a MCE for determination of cholesterol. Hydrogen peroxide was generated from the oxidation of cholesterol with cholesterol oxidase （ChOx） and was detected electrochemically at a downstream gold （Au） wire electrode by amperometry. Various parameters, such as the detection potential, concentration of running buffer, pH of running buffer, separation voltage, injection time, and concentration of ChOx, were studied. The migration time of cholesterol is less than 100s and the calibration curve is linear from 50 mg.dL-1 to 250 mg-dL-1 with the coefficient of determination （R2） of 0.9955. Therefore, this proposed assay is very rapid and sensitive for the detection of cholesterol.
文摘Fused-silica capillaries used in capillary zone electrophoresis were statically coated with γ- glycidoxypropyltrimethoxysilane and epoxy polymer in order to suppress wall adsorption in the separation of proteins. It has been shown that a significant decrease in adsorption was obtained and eletroosmotic flow was the diminished in the pH range 3-5. However with higher pH values, appreciable peak deformation and decreases in the resolving power were observed. Under pH 5, the epoxy polymer coating was shown to be quite stable and exhibited reproducible separations from run-to-run and day-to-day over a period of time.
文摘The samples of licorice (Glycyrrhiza uralensis Fisch.) from 14 different cultivated areas were determined by the method of high Performance Capillary Electrophoresis (HPCE) for the contents of glycyrrihizic acid (GA) in root. The results showed that the licorice plants come from various cultivated areas of China has different contents of GA. The GA content of licorice from Zhaodong in Heilongjiang Province is the highest, followed by those from E抰uoke, Chifeng, and Hangjin Banner in Inner Mongolia. Some suggestions for establishing the production base of licorice were put forward based on the study.
