发布求助
文献互助 智能选刊 最新文献

Journal of capillary electrophoresis and microchip technology最新文献

筛选
英文 中文
Effect of nonaqueous buffer modifiers on the capillary electrophoresis-mass spectrometry analysis of peptides. 非水缓冲剂对多肽毛细管电泳-质谱分析的影响。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Leesa J Deterding, Morteza Khaledi, Kenneth B Tomer
{"title":"Effect of nonaqueous buffer modifiers on the capillary electrophoresis-mass spectrometry analysis of peptides.","authors":"Leesa J Deterding,&nbsp;Morteza Khaledi,&nbsp;Kenneth B Tomer","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The effect of the addition of nonaqueous modifiers in capillary electrophoresis at varying concentrations was determined using synthetic peptides as model compounds. The electroosmotic flow is compared in each of the binary solvent systems and, in all cases, an increase in the concentration of organic solvent resulted in a decrease in the electroosmotic flow. The electrophoretic mobilities of each peptide were calculated and, in the case of acetonitrile, little or no change was observed in the peptide mobilities. In general, a decrease in the electrophoretic mobilities of the peptides was observed for increasing concentrations of methanol and N-methylformamide. The compatibility of each modifier at 25% (vol/vol) for use with mass spectrometric detection was evaluated. From our data, the addition of acetonitrile to the CE buffer appears to be the most compatible with mass spectrometry due to shorter analysis times and increased sensitivities in comparison to methanol and N-methylformamide.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"11-8"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22394572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Dr. Robert T. Kennedy. 罗伯特·t·肯尼迪博士。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Norberto A Guzman
{"title":"Dr. Robert T. Kennedy.","authors":"Norberto A Guzman","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"2A-3A"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22394568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Monitoring the unfolding and refolding of creatine kinase by capillary zone electrophoresis. 毛细管区带电泳监测肌酸激酶的展开和再折叠。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Bin Deng, Qin-hua Ru, Guo-An Luo
{"title":"Monitoring the unfolding and refolding of creatine kinase by capillary zone electrophoresis.","authors":"Bin Deng,&nbsp;Qin-hua Ru,&nbsp;Guo-An Luo","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Creatine kinase (ATP: creatine N-phosphotransferase; EC 2.7.3.2) plays a key role in the energy transport, muscle contraction, and reproduction of adenosine triphosphate (ATP). The activity of the enzyme is dependent on the correct folding of the peptide. We observed the unfolding and refolding processes of the creatine kinase of rabbit muscle, and concluded that traditional electrophoresis technology is unsuitable for the transient folding intermediates formed during protein unfolding and refolding. Capillary zone electrophoresis with diode array detection was used to monitor the unfolding and refolding of rabbit creatine kinase under different pretreatments and experimental conditions. This technique provides a simple, sensitive, and rapid approach to protein unfolding and refolding.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"7-10"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22394573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Large-volume sample stacking in nonaqueous capillary electrophoresis using alcoholic run buffers. 用酒精缓冲液进行非水毛细管电泳的大体积样品堆积。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Jaeho Jang, Yoon-Mo Koo, Doo Soo Chung
{"title":"Large-volume sample stacking in nonaqueous capillary electrophoresis using alcoholic run buffers.","authors":"Jaeho Jang,&nbsp;Yoon-Mo Koo,&nbsp;Doo Soo Chung","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A straightforward method for stacking an extremely large volume of a sample solution containing weakly acidic organic compounds was developed. By using alcohols such as methanol, ethanol, and 1-propanol as run buffer solvents, the electroosmotic flow was suppressed, so that analyte anions could proceed to the outlet vial against the electroosmotic flow under a reverse voltage. This effect made large-volume sample stacking possible for large anions using a bare, fused-silica capillary without intermediate polarity switching. The detection limits were in the low nanomolar range with conventional UV absorbance detection. The applicability of the technique to other organic solvents was also tested.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"19-24"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22393835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of bipyridylium herbicides by capillary zone electrophoresis. 毛细管区带电泳分析联吡啶类除草剂。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Angela Santilio, Barbara Casentini, Mariangela Spagnoli, Roberto Dommarco
{"title":"Analysis of bipyridylium herbicides by capillary zone electrophoresis.","authors":"Angela Santilio,&nbsp;Barbara Casentini,&nbsp;Mariangela Spagnoli,&nbsp;Roberto Dommarco","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The separation of paraquat, diquat, and difenzoquat bipyridilium herbicides and ethyl viologen as internal standard is shown. The separation has been carried out using a fused silica capillary with a high-sensitivity detection cell for a capillary electrophoresis system and with a diode array detector. The experiments have been performed using phosphate buffer 50 mM at pH = 4 and pH = 7. The effect of methanol has also been studied when used as an organic modifier. Different voltages and electrokinetic conditions have been used to optimize the separation. Twenty Kv voltage and 10 Kv for 3 sec for injection have been found to be reliable conditions of separation at pH 4 without organic modifier.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22394569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Capillary electrophoretic assay of acyl-CoA hydrolase activity. 酰基辅酶a水解酶活性的毛细管电泳测定。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Sree Divya Panuganti, Kathleen Healy Moore
{"title":"Capillary electrophoretic assay of acyl-CoA hydrolase activity.","authors":"Sree Divya Panuganti,&nbsp;Kathleen Healy Moore","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Acyl-CoA hydrolases catalyze the hydrolysis of fatty acyl CoA thioesters to free fatty acids and coenzyme A. These enzymes play an important role in the maintenance of cellular acyl-CoA and free CoASH pools and in the detoxification of nonphysiological metabolites. The assays most commonly used for acyl-CoA hydrolase quantitation are spectrophotometric and radioisotopic methods, both of which have limitations. In this study, capillary electrophoresis was used as an effective analytical technique to characterize rat liver peroxisomal acyl-CoA hydrolase reactivity using octanoyl-CoA as a substrate at different reaction conditions. The substrate and product of acyl-CoA hydrolase were identified by their migration times and quantitated using the peak areas. The enzyme activity exhibited a typical Michaelis-Menten pattern with increasing octanoyl-CoA concentration. The apparent Km and Vmax of octanoyl-CoA hydrolysis were determined using the enzyme activity at varying substrate concentrations. The rate of hydrolysis of octanoyl-CoA with increasing enzyme concentration appeared as a hyperbolic plot. The enzyme activity became elevated with increasing incubation time, showing the highest activity at 20 min, after which it started to decrease as the incubation time increased. Thus, capillary electrophoresis has been shown to be an effective, rapid, and reproducible method for the characterization of acyl-CoA hydrolase.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"25-31"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22394575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Capillary electrophoresis separation of autocondensation glycation products of glucosamine. 葡萄糖胺自缩合糖基化产物的毛细管电泳分离。
Journal of capillary electrophoresis and microchip technology Pub Date : 2003-01-01
Xinfeng Zhang, Yue Ma, Hong Liu, Paula F G De Sa, Phyllis R Brown, Joel A Dain
{"title":"Capillary electrophoresis separation of autocondensation glycation products of glucosamine.","authors":"Xinfeng Zhang,&nbsp;Yue Ma,&nbsp;Hong Liu,&nbsp;Paula F G De Sa,&nbsp;Phyllis R Brown,&nbsp;Joel A Dain","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Glucosamine nonenzymatically forms autocondensation glycation products under physiological conditions. Many studies have reported the effectiveness of oral doses of glucosamine alone or in combination with the galactosamine containing chondroitin in treating osteoarthritis. However, none of these studies has considered whether it is the glucosamine itself and/or one or more of its autocondensation products that exert this effect. A capillary electrophoresis method was developed to monitor the nonenzymatic formation of autocondensation glycation products of glucosamine, galactosamine, and mannosamine under physiological conditions. Major components were detected and separated by CE with a UV detector. The effects of concentration and incubation time on product species were determined. The method described is simple, rapid, and effective.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"8 1-2","pages":"33-7"},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22393838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Determination of lamivudine/didanosine/nevirapine in human serum using capillary zone electrophoresis. 毛细管区带电泳法测定人血清中拉米夫定/二腺苷/奈韦拉平的含量。
Journal of capillary electrophoresis and microchip technology Pub Date : 2002-09-01
Bin Fan, James T Stewart
{"title":"Determination of lamivudine/didanosine/nevirapine in human serum using capillary zone electrophoresis.","authors":"Bin Fan,&nbsp;James T Stewart","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A combination of the anti-HIV drugs lamivudine (3TC), didanosine (ddI), and nevirapine were separated and quantitated in human serum with capillary zone electrophoresis (CZE). The effects of various factors such as run buffer concentration and pH on the separation were investigated. The optimized resolution was achieved with a run buffer containing 100 nM N,N-dimethyloctylamine in 80 mM phosphate buffer (pH 2.5). Diltiazem was chosen as the internal standard. All analytes were separated within 10 min at 30 degrees C with a voltage of +20 kV and UV detection at 210 nm.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"7 5-6","pages":"103-6"},"PeriodicalIF":0.0,"publicationDate":"2002-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22211643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Electrophoretic mobilities and migrating analytes: Part 1: Relationships. 电泳迁移率和迁移分析物。第1部分:关系。
Journal of capillary electrophoresis and microchip technology Pub Date : 2002-09-01
Reginald F Cross, Margaret G Wong
{"title":"Electrophoretic mobilities and migrating analytes: Part 1: Relationships.","authors":"Reginald F Cross,&nbsp;Margaret G Wong","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The molecular radii (r) of a series of peptides have been determined by molecular modeling. With these data, it is shown that electrophoretic mobility (mu(ep)) is proportional to 1/r2, and that the dependence presented in textbooks (mu(ep) infinity 1/r) is wrong. Use of the approximately equivalent, mass-based Offord equation is discussed, and other relevant considerations are presented.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"7 5-6","pages":"119-24"},"PeriodicalIF":0.0,"publicationDate":"2002-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22211647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Determination of physostigmine and pyridostigmine in pharmaceutical formulations by capillary electrophoresis. 毛细管电泳法测定制剂中毒力斯的明和吡哆斯的明。
Journal of capillary electrophoresis and microchip technology Pub Date : 2002-09-01
Josef Havel, Jiri Patocka, Gastón Bocaz
{"title":"Determination of physostigmine and pyridostigmine in pharmaceutical formulations by capillary electrophoresis.","authors":"Josef Havel,&nbsp;Jiri Patocka,&nbsp;Gastón Bocaz","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Physostigmine (PHY) and pyridostigmine (PYR) are two important anticholinesterase compounds with several clinical uses. Recently, PHY has been investigated for the treatment of senile dementia in Alzheimer's disease. However, both PHY and PYR have gained importance as antidotes for anticholinergic drugs. In military medicine, PYR is used as a prophylactic against nerve gas poisoning and was used in Saudi Arabia during the Gulf War in 1991. A new capillary zone electrophoresis (CZE) method for the rapid determination of PHY and PYR in pharmaceutical preparations has been developed. An untreated fused-silica capillary tube (75 microm i.d., 44 cm total length, 36.5 cm length to the detector) was employed with detection at 200 and 270 nm for PHY and PYR, respectively. The optimal separation conditions for PHY were: 50 mM boric acid-HCl buffer (pH 3.25) with 30 mM NaClO4, electrokinetic injection for 5 sec at -5 kV, temperature 25 degrees C, and separation voltage 15 kV. The optimal separation conditions for PYR were: 20 mM phosphate buffer (pH 7), electrokinetic injection for 20 sec at -10 kV, temperature 25 degrees C, and separation voltage 15 kV. The limits of detection (LOD, S/N = 3) were 70 and 60 ppb for PHY and PYR, respectively. The method can be used for the monitoring of possible main degradation products in tablets of military antidote formulations.</p>","PeriodicalId":15060,"journal":{"name":"Journal of capillary electrophoresis and microchip technology","volume":"7 5-6","pages":"107-12"},"PeriodicalIF":0.0,"publicationDate":"2002-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"22211652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信