包建民
主要致力于生物化学、分析化学与蛋白质药物研究方面的工作。
个性化签名
- 姓名:包建民
- 目前身份:
- 担任导师情况:
- 学位:
-
学术头衔:
博士生导师
- 职称:-
-
学科领域:
分析化学
- 研究兴趣:主要致力于生物化学、分析化学与蛋白质药物研究方面的工作。
暂无
-
主页访问
2330
-
关注数
0
-
成果阅读
854
-
成果数
11
【期刊论文】Characterization and inhibition study of MurA enzyme by capillary electrophoresis
包建民, H. Jian Dai, Christian N. Parker, James J. Bao *
Journal of Chromatography B, 766(2001)123-132,-0001,():
-1年11月30日
A capillary electrophoresis-based enzyme assay for UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) is described. This method, based on UV detection, provides baseline separation of one of the reaction products, enolpyruvyluridine 59-diphospho-N-acetylglucosamine (EP-UDP-GlcNAc), from substrates phosphoenolpyruvate (PEP) and uridine 59-diphospho-N-acetylglucosamine (UDP-GlcNAc) within 4 min. The other product, phosphate, is not detectable by UV at 200 nm. Quantitation of individual components, substrates or product, can be accomplished based on the separated peaks. This methodology was used to determine the Michaelis constant, K, and product formation rate constant, K, for MurA. m cat Additionally, the CE method was used to evaluate the inhibition effects on MurA using one specific compound as an example. By following similar procedures, the apparent K values in the presence of different inhibitor concentrations were mdetermined. The inhibition constant, K, can be determined from these apparent K values. In addition, this CE method can i m be used to study the inhibition mechanism. The principle of this approach is generally applicable to other enzyme studies.
MurA enzyme, Enzymes
-
70浏览
-
0点赞
-
0收藏
-
0分享
-
155下载
-
0评论
-
引用
包建民, Jian Dai, Jian Tu, LaShonda N. Anderson, James J. Bao *, Changsheng Liu †, Bryan Quay †, and Kenneth R. Wehmeyer
606 LCGC NORTH AMERICA VOLUME 20 NUMBER 7 JULY 2002,-0001,():
-1年11月30日
The authors evaluated the performance of multiplexed capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) for highthroughput separation-based assays using fluorescein isothiocyanate as a model compound and fluorescein as an internal standard. They assessed performance areas, including linearity of response, precision of migration time, peak area and peak height response with and without internal standard correction, limit of detection, cross-talk between adjacent capillaries, and reproducibility of performance over time. In this article, they also discuss representative data for the application of multiplexed CE-LIF to screening enzyme inhibitors and measuring endogenous enzyme levels.
-
81浏览
-
0点赞
-
0收藏
-
0分享
-
104下载
-
0评论
-
引用
【期刊论文】Chemical Reagents and Derivatization Procedures in Drug Analysis
包建民, Neil D. Danielson and Patricia A. Gallagher, James J. Bao
,-0001,():
-1年11月30日
This article describes both pre- and postcolumn derivatization chemistry used in conjunction with either chromatography or capillary electrophoresis (CE) to facilitate the determination of drugs. Generally, only prederivatization is used in gas chromatography (GC), principallyto enhance the volatility, temperature stability, and/or detectability. The GC section considers derivatization of drugs by reagent class: alkylation, acylation, and silylation. The GC sample handling section describes an approach which combines the extraction and derivatization steps together. Both pre- and postcolumn derivatization are common approaches for high-performance liquid chromatography (HPLC) and many of these methods have been adapted for CE. Derivatization for HPLC is often directed toward aliphatic amines, carboxylic acids, or alcohols that are difficult to detect at low levels by absorbance, luminescence, or electrochemical means. In addition, small hydrophilic molecules upon prederivatization are often converted into larger more hydrophobic compounds, making reversed-phase HPLC easier or even feasible. TheHPLC section considers derivatization of drugs based on type: alkaloids, amines, antibiotics, barbiturates, carbonyl compounds and carboxylic acids, catecholamines, hydroxy compounds, steroids, and sulfur compounds. For the GC and HPLC sections, tables are included giving the structures of the more important derivatizing agents, the analytes, and the corresponding reaction products. A brief rationale for derivatization chemistry with CE concludes this article. For CE, derivatization is often done to improve detectability since the path length for absorbance detection is very short and fluorescence can be effective using laser-based systems.
-
110浏览
-
0点赞
-
0收藏
-
0分享
-
1634下载
-
0评论
-
引用
【期刊论文】Fluorogenic assay for b-glucuronidase using microchip-based capillary electrophoresis
包建民, Dustin E. Starkey a, Arum Han b, James J. Bao c, Chong H. Ahn b, Kenneth R. Wehmeyer c, *, Marla C. Prenger c, H. Brian Halsall a, William R. Heineman
Journal of Chromatography B, 762(2001)33-41,-0001,():
-1年11月30日
Microchip capillary electrophoresis (CE) was used with a model enzyme assay to demonstrate its potential application to combinatorial drug screening. Hydrolysis with b-glucuronidase of the conjugated glucuronide, fluorescein mono-b-Dglucuronide (FMG), liberated the fluorescent product, fluorescein. FMG and fluorescein were detected by fluorescence, with excitation and emission at 480 and 520 nm, respectively. Microchip CE was used to separate FMG and fluorescein. Fluorescein production was monitored to assess b-glucuronidase activity. Michaelis-Menten enzyme kinetics analysis yielded the K value. The results were compared with those from experiments done by conventional CE. The K value form mb-glucuronidase with FMG is being reported for the first time as 18 mM. The inhibition of b-glucuronidase by the competitive inhibitor D-saccharic acid-1,4-lactone (SL) was also determined using microchip CE. Reactions were done with various concentrations of inhibitor and constant b-glucuronidase and FMG concentrations. A dose–response plot was acquired and the IC value for SL was determined to be 3 mM.
Microchips,, CE, b-Glucuronidase, Enzymes
-
63浏览
-
0点赞
-
0收藏
-
0分享
-
96下载
-
0评论
-
引用
【期刊论文】Characterization and inhibition study of MurA enzyme by capillary electrophoresis
包建民
,-0001,():
-1年11月30日
-
73浏览
-
0点赞
-
0收藏
-
0分享
-
96下载
-
0评论
-
引用
包建民, James J. Bao *, Nikhil J. Parekh, Amir Shuja
Journal of Chromatography B, 720(1998)129-140,-0001,():
-1年11月30日
Reliable methods based on capillary electrophoresis (CE) have been developed for the separation and quantitation of azimilide, an antiarrhythmic drug under development at Procter & Gamble Pharmaceuticals (P & GP). Both capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MECC) were employed in the separation of azimilide from its impurities, degradants and/ or metabolites. Separation of azimilide from NE-11178, F-410, F-1054 and F-1292 was obtained by MECC at pH 9 with 50 mM sodium dodecyl sulfate (SDS). The separation of azimilide and NE-10171, a key metabolite of azimilide, was difficult because their structures differ by only a single methyl group. The best separation was achieved under acidic pH conditions with cetyltriethyl ammonium chloride (CTAC) additive in the buffer. All of the CE separations were completed within a substantially shorter time and with better resolution than the corresponding high-performance liquid chromatography (HPLC) separations. Quantitation was done with azimilide and 2 NE-10171. Calibration curves ranging from 10 to 1000 mg/ml were obtained with R greater than 0.997 for both azimilide and NE-10171. The back-calculated concentrations of the calibration standards and the recoveries of the quality control (QC) samples were within the acceptance range currently used for HPLC methods. These results demonstrated the viability of CE as an alternative technique for drug metabolism studies in support of pharmaceutical development.
Azimilide
-
74浏览
-
0点赞
-
0收藏
-
0分享
-
40下载
-
0评论
-
引用
包建民
,-0001,():
-1年11月30日
-
73浏览
-
0点赞
-
0收藏
-
0分享
-
49下载
-
0评论
-
引用
【期刊论文】Ultramicro enzyme assays in a capillary electrophoretic system
包建民, Jianmin Bao and Fred E. Regnier
Journal of Chromatography6,0 8(1992) 217-224,-0001,():
-1年11月30日
ng and mixed with the reagents in the capillary by electrophoretic mixing. Enzyme activity was assayed by electrophoresing the product, reduced nicotinamide adenine dinucleotide phosphate, to the detector where it was detected at 340 nm. Under constant potential, the transport velocity of enzyme and the product was generally different. This caused product to be separated from the enzyme after it was formed. Because product formation was much faster than the rate of enzyme-product separation, product accumulated. The amount of accumulated product was inversely related to operating potential. In the extreme case, the operating potential was zero. Zero potential assays were generally carried out by electrophoresing the enzyme partially through the capillary and then switching to zero potential. This capillary was left at zero potential for several minutes to allow additional product to accumulate. After this additional amplification step, potential was again applied and the product transported to the detector. Product formed under constant potential appears as a broad peak with a flat plateau. When the voltage is switched to zero at intermediate migration distance, a peak will be observed on top of this plateau. Either the eight of the plateau or the area of the peak may be used to determine enzyme concentration. The lower limit of detection was 4.6 10-r’ mol of glucose-6-phosphate dehydrogenase.
-
97浏览
-
0点赞
-
0收藏
-
0分享
-
67下载
-
0评论
-
引用
【期刊论文】HIGH-THROUGHPUT DETERMINATION OF LOGD VALUES BY LC/MS METHOD
包建民, JENNY D. VILLENA, KEN WLASICHUK, DONALD E. SCHMIDT JR., and JAMES J. BAO
,-0001,():
-1年11月30日
-
76浏览
-
0点赞
-
0收藏
-
0分享
-
76下载
-
0评论
-
引用
包建民, Alfred Corey, BS, Jeffrey Agnew, MA, James Bao, PhD, Philip Bryson, MB, Chb, MRCGP, Patrick Comer, MS, Susan Griffith, MRCP, and Junfang Li
Reprinted from THE JOURNAL OF CLINICAL PHARMACOLOGF, October, 1997,-0001,():
-1年11月30日
Aziriulide is a new class III antiarrhythmic drug that blocks K- channnels. To determine the feeects of age and gender on azimilide pharmacokinetics, a sigle 150-mg oral dose was administered to 66 healthy vohunteers in a 3
-
68浏览
-
0点赞
-
0收藏
-
0分享
-
50下载
-
0评论
-
引用