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.

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.

Study of Interaction between Red-tide Toxin, Domoic Acid and Double stranded DNA by Capillary Zone Electrophoresis

The interactions between amnesic red-tide toxin, domoic acid (DA) and 14mer double-stranded DNA (dsDNA with three kinds of sequences) were studied by capillary zone electrophoresis (CZE). For the dsDNA with a sequence of 5'-CCCCCTATACCCGC-3', the amount of free dsDNA decreases with the increase of added DA; and the signal of DA-dsDNA complex was observed. Meanwhile, the other two dsDNAs, 5'-(C)12GC-3' and 5'-(AT)7-3', the existence of DA could not lead to the change of dsDNA signal and indicated that there is no interaction between DA and these two dsDNAs.

Evaluation of The Interaction between Netropsin and Double Stranded DNA by Capillary Zone Electrophoresis

Capillary zone electrophoresis (CZE) was applied to study the interaction between netropsin and a 14mer double stranded DNA (dsDNA). The binding constant of this interaction calculated from Scatchard plot was (1.070.10)×105 (mol/L)-1. The binding stoichiometry was 1:1. The use of polyacrylamide coated capillary showed better effect in the analysis of DNA than noncoated capillary.

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.

Separation of chiral drugs with sulfobutylether-β-cyclodextrin bycapillary zone electrophoresis

Sulfobutylether－β－cyclodextrin（SBE－β－CD）was used as a chiral selector tor separatingten chlral drugs with resolution 1．2 by capillary zone electrophoresls（CZE）， The backgroundelectrolylc solution comprised of 120 mmol／L Britton－Robinson buffer（BRB） containing1 ～10mmol／L SBE－β－CD with the pH value adjusted from 5．0－6．8． Five of the drugs were better resolvedthan those previously reported with neutral CDs．

Ionic Liquid and HP-β-CD Modified Capillary Zone Electrophoresis to Separate Hyperoside, Luteolin and Chlorogenic Acid

Ionic liquid （1-ethyl-3-methylimidazolium tetrafluoroborate, 1E-3MI-TFB） and HP-β- CD as modifier was added to the buffer to separate hyperoside, luteolin and chlorogenic acid. Experiments explored the effect of concentration of 1E-3MI-TFB and HP-β-CD on separation. The results indicated that 1.0 mmol/L HP-β-CD and 1%0 （v/v） 1E-3MI-TFB added to the buffer simultaneously could achieve a good compromise of resolution and analysis time. Capillary experiments and UV spectra indicated that there was interaction between 1E-3MI-TFB and analytes.

Capillary Zone Electrophoresis Investigation of Interactions between Granulocyte-colony Stimulating Factor and Dextran Sulfate/Carrageenan Oligosaccharide

The interactions between granulocyte-colony stimulating factor (G-CSF) and dextran sulfate / κ-carrageenan oligosaccharide were studied by capillary zone electrophoresis. Dextran sulfate could strongly interact with G-CSF and the complex was detected. The binding constant and stoichiometry were determined to be 1.2×106 (mol/L)-1 and 3:1, respectively. However, the interaction between κ-carrageenan oligosaccharide and G-CSF was not found.

Analysis of Phenolic Compounds in Coke Plant Wastewater by Capillary Zone Electrophoresis with Inhibited Chemiluminescence Detection

A capillary electrophoresis（CE） with on-line inhibited chemiluminescence （CL） detection was firstly used for the simultaneous analysis of benzenediol isomers and phenol. It is based on the quenching effect of benzenediol isomers and phenol on the chemiluminescence reaction of luminol with potassium ferricyanide in sodium hydroxide medium. Under the optimum conditions, the four phenols were baseline separated and detected in less than 10 rain. The detection limits （S/N=3） for hydroquinone, resorcinol, catechol and phenol were 2.9×10^-8 mol/L, 3.7×10^-7 mol/L, 8.4×10^-8 mol/L and 4.4×10^-6 mol/L, respectively. Finally, the presented method has been successfully applied to real sample.

Screening of chemokine receptor CCR4 antagonists by capillary zone electrophoresis

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)-carbamlyl]-methyl-4-oxo-thiazolidin-3-yl)-N-(3-morpholin-4-yl-propyi)-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-I 1,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.

Studies of Active Ingredients in Cough Syrup by Capillary Zone Electrophoresis with Amperometric Detection

The present paper covers a simple, reliable and reproducible method, based on capillary zone electrophoresis(CZE) with amperometric detection(AD), for the separation and the determination of ephedrine hydrochloride, promethazine hydrochloride and codeine phosphate. Under the optimal conditions, the three analytes were base-line separated completely within 16 min. Good linear relationships between the peak heights and the concentrations of the three analytes were obtained with the correlation coefficients better than 0 9993. The method was directly applied to the determination of the active ingredients in pharmaceutical preparations and the assay results were satisfactory.

Analysis of Amino Acids in a Single Human Red Blood Cell by Capillary Zone Electrophoresis with Intracellular NDA- derivatization and Electrochemical Detection

A novel method for determination of amino acids in individual human red blood cells has been developed. In this method, the derivatization reagents (NDA and CN-) are introduced into living cells by electroporation. After completion of derivatization, the amino acids in a single cell is determined by capillary zone electrophoresis with end-column amperometric detection.

Determination of Five Organic Acids in Radix Isatidis by Column Partition Chromatography and Capillary Zone Electrophoresis柱分配色谱-毛细管区带电泳联用分析板蓝根中五种微量有机酸(英文)

Aim To determine five organic acids in Radix Isatidis . Method The extraction method and the column partition chromatographic conditions were studied. Then a capillary zone electrophoretic method was set up for the determination. Results The linear ranges of quinazolinone acid, n anthranilic acid, benzoic acid, salicylic acid, and syringic acid were 5 52-92 0 μg·mL -1 , 5 12-102 μg·mL -1 , 2 28-84 4 μg·mL-1 , 4 78-159 μg·mL -1 , and 1 74-87 0 μg·mL -1 respectively. Conclusion The established method is accurate and simple.

Assay of Histamine in Single Mast Cells by Capillary Zone Electrophoresis with Electrochemical Detection

Capillary zone electrophoresis was employed for the analysis of histamine in single rat peritoneal mast cells using an amperometric detector. In this method, individual mast cells and then 0.02 mol/L NaOH as a lysing solution are injected into the front end of the separation capillary. A cell injector was constructed for easy injection of single cells. Histamine in single mast cells has been identified and quantified.

Detection and Separation of Inorganic Cations in Natural, Potable, and Wastewater Samples Using Capillary Zone Electrophoresis with Indirect UV Detection

Capillary zone electrophoresis (CZE) is a sensitive and rapid technique for determining traces of inorganic cations in water samples. CZE with indirect UV-diode array detection (CZE-DAD) was utilized to identify several inorganic cations in natural, potable, and wastewater samples. A pH 4.35 background electrolyte system was employed and consisted of 15 mM imidazole, 8 mM malonic acid, 2 mM 18-crown-6 ether as complexing agents, 10% v/v methanol as an organic modifier with indirect absorbance reference at 214 nm. The CZE method involved electromigration injection at 5 kV for 5 s, a separation voltage of 20 kV at 25℃, and a detection wavelength of 280 nm. Six main cations (ammonium , potassium K+, calcium Ca2+, sodium Na+, magnesium Mg2+, and lead Pb2+) were tested, and all but lead, were detected in the water samples at concentrations between 0.03 and 755 ppm with a detection limit ranging between 0.023 and 0.084 ppm. The successful evaluation of the proposed methodology allowed us to reliably detect and separate six metal ions in different water samples without any pretreatment. All water samples were collected from Northern New York towns and the Raquette River water system, the third longest river in New York State and the largest watershed of the central and western Adirondacks.

A Novel Method for Quantification of Circulating DNA in Serum by Capillary Zone Electrophoresis

In this paper, we first presented a novel method for quantification of circulating DNA in human serum based on capillary zone electrophoresis with laser-induced fluorescence detection (CZE-LIF). The serum was digested by proteinase to release free DNA, and then CZE-LIF system was used for the quantification of total circulating DNA. This method was successfully used to quantify the circulating DNA levels in sera from healthy individuals and certain cancer patients. We found the significantly elevated circulating DNA levels in certain prostate cancer patients. Our results demonstrated that CZE-LIF system has good linearity, excellent sensitivity (0.5 ng/mL DNA), satisfactory reproducibility (RSDs in one day and between days were both less than 5%) and reliability, and is well suitable to the quantification of the circulating DNA in human serum or plasma.

Separation and Determination of Bases by Capillary Zone Electrophoresis

The present paper covers the separation and determination of cytosine , 9-N-di- hydroxypropyltheophylline , theobromine , adenine , guanine , uracil , theophylline , 1-hydroxyethyl-5-fluorouracil , xanthine , uric acid , 6-mercaptopurine , 5-fluo- rouracil and 1 -propionyloxyuracil by capillary zone electrophoresis. In an uncoated silica capillary(70 cm ×75 μm i. d. effective length 63 cm) , thirteen bases could be separated within 1 1 min under the optimum conditions : 0. 01 mol/L(pH 10. 0) bo- rate buffer, 40℃ , 15 kV, 260 nm and 2 s load. Efficiencies up to 3. 1 ×105 theoreti- cal plates (4. 9 ×105 plates/m) were achieved.

Determination of Size Distribution of Nano-particles by Capillary Zone Electrophoresis

A new method was developed for the determination of the size distribution of nano-particles by capillary zone electrophoresis (CZE). Scattering effect of nanoparticles was studied . This method for the determination of size distribution was statistical.