Interactions Between Thrombin and Natural Proudcts of Coreopsis tinctoria Nuttt. and Cistanche deserticola Ma. in Capillary Zone Electrophoresis

Aim A capillary zone electrophoretic method （CZE） was used to determine the interactions between natural products and thrombin. Methods Samples containing natural products and thrombin at various ratios were incubated at 25 ℃ and then were separated by CZE with Tris-acetate buffer at pH 7.2. Each run could be accomplished within 5 min. Results In CZE, the peak width broadened due to the affinity interaction between natural products and thrombin. Compared with positive and negative control, the natural products （CB-1, CB-2） from Coreopsis tinctoria Nuttt. interacted with thrombin; CB-3 from Coreopsis tinctoria Nuttt. and HC-1, HC-2, HC-3 from Cistanche deserticola Ma. did not bind to thrombin. Both qualification and quantification characterizations of the binding were determined. Conclusion The established method is capable of sensitive and fast determination of natural products and thrombin interactions, it can be employed as an alternative method.

Determination of Magnolol and Honokiol by Non-aqueous Capillary Electrophoresis

Two active principles in traditional Chinese medicine Magnolia officinalis, magnolol and honokiol, were successfully separated by means of nonaqueous capillary electrophoresis. The effect of the composition of a nonaqueous buffer on column efficiency and resolution, and the effect of acid additives on peak shapes were researched. The separation was conducted with a running buffer in a mixture of methanol/aeetonitrile/formamide （ volume ratio ： 1 ： 2 ： 2 ）, in which the concentrations of Tris, acetic acid, and water were 60 retool/L, 0. 04 mmol/L and 5% （ volume fration）, respectively, and the pH^＊ （apperent pH） of the running buffer was 8.96. Magnolol and honokiol were separated on baseline within 20 min. The relative standard deviation of the analytes＇ concentrations in the sample is 1.32% for magnolol and 1.60% for honokiol, and the recoveries of the spiked sample are 98.4% for magnolol and 98. 0% for honokiol, respectively.

Analysis of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection

A new method for the determination of arecoline in Semen Arecae decoction pieces by microchip capillary electrophoresis with contactless conductivity detection （MCE-CCD） was proposed. The effects of various electrophoretic operating parameters on the analysis of arecoline were studied. Under the optimal conditions, arecoline was rapidly separated and detected in 1 rain with good linearity over the concentration range of 20 1500 uM （r2=0.9991） and the detection limit of 5 uM （S/N=3）. The method was used for the analysis of arecoline satisfactorily with a recovery of 96.8 -104%.

A Novel Method for Studying the interaction of Macromolecule with Small Molecule by Means of Affinity Capillary Electrophoresis

A novel capillary electrophoresis method coupled with on-line microdialysis using an attachable electrode has been developed to study the interaction of macromolecule with small molecule. The binding constants of bovine serum album (BSA) with D,L-tryptophan (Trp), sulfamethoxazole (SMZ) with trypsin and chymotrypsin were determined. These values are 2.3 x 10(4)L/mol for BSA-L-Trp; 1.77 x 10(3) L/mol for BSA-D-Trp in pH 7.4, 50 mmol/ L phosphate; 1.4 x 10(4) L/mol for SMZ- trypsin and 6.0 x 10(3) L/mol for SMZ-chymotrypsin in pH 6.5, 25 mmol/L Tris buffer. The proposed method has merits of speed, low sample consumption and readily available to be performed in desired physiological conditions.

A Peptides Migration Model in capillary Zone Electrophoresis

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.

Separation of Nucleotides in Swine Tissues Using Capillary Zone Electrophoresis

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.

Direct detection of tryptophan enantiomers in urine using the chiral recognition of cyclodextrin by capillary electrophoresis

Racemic tryptophan was separated with resolution 1.3 by CE. In 10 mM H2PO4 containing triethanolamine salt of pH2.8 ahnost saturated α-CD was used as chiral reagent. For the first time L- and D-tryptophan enantiomers in human urine can be detected in 20 minute without pretreatment.

Preparation of β-Cyclodextrin Modified FusedSilica Capillary and Its Application inCapillary Electrophoresis Enantiom eric Separation

A simple type of chiral selector immobilized capillaries was prepared and applied to the separation of some enantiomers by capillary electrophoresis(CE) without chiral selective reagents in a buffer solution. β Cyclodextrin (CD) was bonded to the inner wall of fused silica capillary with the aid of 3 (2 cyclooxypropoxyl) propyl trimethoxy silane or 3 aminopropyltriethoxyl silane as bridge. The synthesis conditions such as reaction temperature, reaction ratios, solvents were optimized. The stability and reproducibility of the CD modified capillaries were studied under different operation conditions. It is satisfactory to apply the capillary to the chiral separation of d,l adrenaline and the atracurium besilate diastereoisomers under the optimized conditions.

Simultaneous determination of berberine,matrine and oxymatrine in traditional Chinese medicines by using nonaqueous capillary electrophoresis

A rapid method for the simultaneous determination of berberine(BBR),matrine(MT)and oxymatrine(OMT)by nonaqueous capillary electrophoresis(NACE)was developed.Optimum separation of the analytes was obtained on a 50cm×50μm i.d.fused-silica capillary using a non-aqueous buffer system of 70mM ammonium acetate,7.0% acetic acid and 10% acetonitrile at 25kV and 20℃.The relative standard deviations(R.S.D.)of the migration times and peak areas of the three active components were 0.06%-0.20% and 0.12%-3.41% for berberine,0.11%-0.60% and 0.74%-1.63% for matrine,0.15% and 0.45% for oxymatrine,respectively.Detection limits of berberine,matrine and oxymtrine were 0.18μg/mL,4.08μg/mL and 4.16μg/mL,respectively.In the tested concentration range,good linear relationships(0.9992 for berberine,0.9988 for matrine and 0.9988 for oxymatrine)were observed.The linear calibration ranges were 0.45-360.0μg/mL for berberine,8.16-408.0μg/mL for matrine and 20.8-416.0μg/mL for oxymatrine.This method has been successfully applied to the phytochemical analysis of alkaloids extracts from two commonly used traditional Chinese herbal drugs:Sophora flavescens Ait.(Kushen)and Cortex phellodendri chinensis(Huangbai)and their medicinal preparations.

Chiral Separation of N-Benzoyl Phenylalanine Methyl Ester by Nonaqueous Capillary Electrophoresis

A successful chiral separation of N-benzoyl phenylalanine methyl ester has been achieved by nonaqueous capillary electrophoresis (NACE) using P-CD as chiral selector in formamide (FA). Some experimental parameters influencing the chiral separation such as concentration of P-CD, ionic strength and apparent pH (pH*) are discussed.

Determination of Roxithromycin Tablets by Capillary Electrophoresis Employing Non-aqueous Media with Square-wave Amperometric Detection

A new method of determination for roxithromycin tablets by non-aqueous capillary electrophoresis (NACE) with square-wave amperometric detection was carried out. Several parameters affecting the NACE-AD determination were studied. The data was modified by spline wavelet least square (SWLS). The method is simple, rapid and highly reliable for routine analysis.

Simultaneous Determination of Clonidine Hydrochloride,Hydrochlorothiazide, and Rutin in Zhenju Jiangya Tablet by Capillary Electrophoresis

Aim To develop a method for the determination of three drug components： clonidine hydrochloride, hydrochlorothiazide and rutin in Zhenju Jiangya tablet. Methods An uncoated capillary tube was used to analyze under 20 kV voltage at 20 ℃. The samples were introduced into the capillary tube by hydrodynamic mode applying 50 kPa for 5 s and detected at 210 nm. Results The linear ranges of clonidine hydrochlofide, hydrochlorothiazide, and rutin were 10 μg· mL^-1 - 100μg· mL^-1, 30μg· mL^-1 - 300 μg· mL^- 1, and 30μg · mL^-1 - 300μg · mL^-1, respectively. Inter-day and intra-day RSD were all below 10.5%. The recoveries were 94.96% for clonidine hydrochloride, 84.45% for hydroehlorothiazide, and 89.88 % for rutin. Conclusion Clonidine hydrochloride, hydrochlorothiazide, and rutin are baseline separated. The method is simple and rapid for simultaneous determination of the three drug components in Zhenju Jiangya tablet.

Determination of Chromate Ion in Water Using High Performance Capillary Electrophoresis

A new rapid method for the analysis of chromate ion in water by using high performance capillary electrophoresis is described. The detection limit is 1.0 mu g/ml by using 100 m mol/l Tris-HCl buffer containing 2 m mol/l 1,6-hexanediamine which was used as an electroosmosis modifier to improve the separation and detection sensitivity.

Enhancement of Selectivity in Capillary Zone Electrophoresis by Adding Ethanolamines or Ethylamines in the Running Buffer

Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom in capillary zone electrophoresis. The reason is due to the reduction of the average apparent mobilities of the analytes.

Application of Simultaneous Technique of Capillary Zone Electrophoresis Photothermal Interference Spectrometry for Monitoring Chelating Reaction of Light Rare Earth with Tribromoarsenazo

A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported.

Polydimethylsiloxane Microchip Capillary Electrophoresis for Determination of Cholesterol

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.

A New Capillary Electrophoresis Apparatus with Piezoelectric Ceramics High Voltage Source and Amperometric Detector

A new capillary electrophoresis apparatus was designed. Piezoelectric ceramics transformer technology was first applied in capillary electrophoresis, a high voltage and stable source was made. Amperometric detector was used in which the working electrode was closely opposite to the end of capillary. The apparatus was characterized in good reproducibility, safety and very low cost.

Simultaneous Detection of 13 Key Bacterial Respiratory Pathogens by Combination of Multiplex PCR and Capillary Electrophoresis

Objective Lower respiratory tract infections continue to pose a significant threat to human health. It is important to accurately and rapidly detect respiratory bacteria. To compensate for the limits of current respiratory bacteria detection methods, we developed a combination of multiplex polymerase chain reaction （PCR） and capillary electrophoresis （MPCE） assay to detect thirteen bacterial pathogens responsible for lower respiratory tract infections, including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catorrholis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Mycoplasma pneumoniae, Legionella spp., Bordetella pertussis, Mycobacterium tuberculosis complex, Corynebactefium diphthefiae, and Streptococcus pyogenes. Methods Three multiplex PCR reactions were built, and the products were analyzed by capillary electrophoresis using the high-throughput DNA analyzer. The specificity of the MPCE assay was examined and the detection limit was evaluated using DNA samples from each bacterial strain and the simulative samples of each strain. This assay was further evaluated using 152 clinical specimens and compared with real-time PCR reactions. For this assay, three nested-multiplex-PCRs were used to detect these clinical specimens. Results The detection limits of the MPCE assay for the 13 pathogens were very low and ranged from 10-7 to 10-2 ng/μL. Furthermore, analysis of the 252 clinical specimens yielded a specificity ranging from 96.5%-100.0%, and a sensitivity of 100.0% for the 13 pathogens. Conclusion This study revealed that the MPCE with high specificity and sensitivity. This assay survey of respiratory pathogens. assay is a rapid, reliable, and high-throughput method has great potential in the molecular epidemiological.

p-Hydrazinobenzenesulfonic Acid Derivatives of Carbohydrates andTheir Capillary Zone Electrophoresis

p-Hydrazinobenzenesulfonic acid is explored as a novel ultraviolet labeling reagent for capillary electrophoresis (CE) of mono- and disaccharides. The labeling reaction takes less than 10 minutes and introduces both of absorption and charge groups into the sugars.