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Morani M, Taverna M, Mai TD. A fresh look into background electrolyte selection for capillary electrophoresis‐laser induced fluorescence of peptides and proteins. Electrophoresis 2019; 40:2618-2624. [DOI: 10.1002/elps.201900084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/14/2019] [Accepted: 05/18/2019] [Indexed: 12/29/2022]
Affiliation(s)
- Marco Morani
- Institut Galien Paris Sud, UMR 8612, Protein and Nanotechnology in Analytical Science (PNAS)CNRSUniv. Paris‐SudUniv. Paris‐Saclay Châtenay‐Malabry France
| | - Myriam Taverna
- Institut Galien Paris Sud, UMR 8612, Protein and Nanotechnology in Analytical Science (PNAS)CNRSUniv. Paris‐SudUniv. Paris‐Saclay Châtenay‐Malabry France
| | - Thanh Duc Mai
- Institut Galien Paris Sud, UMR 8612, Protein and Nanotechnology in Analytical Science (PNAS)CNRSUniv. Paris‐SudUniv. Paris‐Saclay Châtenay‐Malabry France
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2
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Ten-Doménech I, Simó-Alfonso EF, Herrero-Martínez JM. Improving Fractionation of Human Milk Proteins through Calcium Phosphate Coprecipitation and Their Rapid Characterization by Capillary Electrophoresis. J Proteome Res 2018; 17:3557-3564. [PMID: 30156851 DOI: 10.1021/acs.jproteome.8b00526] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This work describes a simple sample pretreatment method for the fractionation of human milk proteins (into their two main groups, whey and caseins) prior to their analysis. The protein-extraction protocol is based on the addition of calcium phosphate to nonadjusted pH human milk. The combination of calcium ions with phosphate results in an effective coprecipitation of caseins. To assess the suitability of this fractionation protocol, the protein extracts were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), LC-MS/MS, and capillary electrophoresis (CE) analysis. The results evidence a significant decrease in contamination of casein fraction with whey proteins and vice versa compared with the conventional isoelectric precipitation of caseins. In addition, CE fraction collection coupled to LC-MS/MS (off-line coupling) has been successfully applied to the identification of minor proteins in this complex matrix. The methodology presented here constitutes a promising tool to enlarge the knowledge of human milk proteome.
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Affiliation(s)
- Isabel Ten-Doménech
- Department of Analytical Chemistry , University of Valencia , C. Doctor Moliner 50 , E-46100 Burjassot , Valencia , Spain
| | - Ernesto Francisco Simó-Alfonso
- Department of Analytical Chemistry , University of Valencia , C. Doctor Moliner 50 , E-46100 Burjassot , Valencia , Spain
| | - José Manuel Herrero-Martínez
- Department of Analytical Chemistry , University of Valencia , C. Doctor Moliner 50 , E-46100 Burjassot , Valencia , Spain
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Abstract
INTRODUCTION This review discusses advances in the field of microsphere testing. AREAS COVERED In vitro release-testing methods such as sample and separate, dialysis membrane sacs and USP apparatus IV have been used for microspheres. Based on comparisons of these methods, USP apparatus IV is currently the method of choice. Accelerated in vitro release tests have been developed to shorten the testing time for quality control purposes. In vitro-in vivo correlations using real-time and accelerated release data have been developed, to minimize the need to conduct in vivo performance evaluation. Storage stability studies have been conducted to investigate the influence of various environmental factors on microsphere quality throughout the product shelf life. New tests such as the floating test and the in vitro wash-off test have been developed along with advancement in characterization techniques for other physico-chemical parameters such as particle size, drug content, and thermal properties. EXPERT OPINION Although significant developments have been made in microsphere release testing, there is still a lack of guidance in this area. Microsphere storage stability studies should be extended to include microspheres containing large molecules. An agreement needs to be reached on the use of particle sizing techniques to avoid inconsistent data. An approach needs to be developed to determine total moisture content of microspheres.
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Affiliation(s)
- Janki V Andhariya
- a School of Pharmacy , University of Connecticut , Storrs , CT , USA
| | - Diane J Burgess
- a School of Pharmacy , University of Connecticut , Storrs , CT , USA
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Cao J, Ding L, Hu W, Chen X, Chen X, Fang Y. Ternary system based on fluorophore-surfactant assemblies--Cu²⁺ for highly sensitive and selective detection of arginine in aqueous solution. Langmuir 2014; 30:15364-15372. [PMID: 25453500 DOI: 10.1021/la5039798] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A new cationic dansyl derivative-based (DIlSD) fluorescence probe was designed and synthesized. Its combination with anionic surfactant SDS assemblies shows enhanced fluorescence intensity and blue-shifted maximum wavelength. Its fluorescence can be slightly quenched by Cu(2+); however, the fluorescence quenching efficiency by Cu(2+) is highly increased upon titration of arginine (Arg). As a result, the ternary system containing the cationic fluorophore, anionic surfactant, and Cu(2+) functions as a highly sensitive and selective sensor to Arg. The optimized sensor system displays a detection limit of 170 nM, representing the highest sensitivity to Arg in total aqueous solution by a fluorescent sensor. Control experiments reveal that the imidazolium groups in the fluorophore, the anionic surfactant, and Cu(2+) all play important roles in the process of sensing Arg. The electrostatic interaction between the cationic fluorophore and anionic surfactants facilitates the binding of imidazolium rings with Cu(2+), the surfactant surface-anchored Cu(2+) is responsible for further binding of Arg, and the electrostatic interaction between anionic surfactants and positively charged amino acids accounts for the selective responses to Arg.
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Affiliation(s)
- Jianhua Cao
- Key Laboratory of Applied Surface and Colloid Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University , Xi'an 710062, P. R. China
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Pobozy E, Sentkowska A, Piskor A. Comparison of three modifications of fused-silica capillaries and untreated capillaries for protein profiling of maize extracts by capillary electrophoresis. J Sep Sci 2014; 37:2388-94. [PMID: 24931305 DOI: 10.1002/jssc.201301236] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 06/02/2014] [Accepted: 06/03/2014] [Indexed: 12/15/2022]
Abstract
In this work, capillary electrophoresis was applied to protein profiling of fractionated extracts of maize. A comparative study on the application of uncoated fused-silica capillaries and capillaries modified with hydroxypropylmethylcellulose, ω-iodoalkylammonium salt and a commercially available neutral capillary covalently coated with polyacrylamide is presented. The coating stability, background electrolyte composition, and separation efficiency were investigated. It was found that for zeins separation, the most stable and efficient was the capillary coated with polyacrylamide. Finally, the usefulness of these methods was studied for the differentiation of zein fraction in transgenic and nontransgenic maize. Zeins extracted from maize standards containing 0 and 5% m/m genetic modification were successfully separated, but slight differences were observed in terms of the zein content. Albumin and globulin fractions were analyzed with the use of unmodified fused-silica capillary with borate buffer pH 9 and the capillary coated with polyacrylamide with phosphate buffer pH 3. In the albumin fraction, additional peaks were found in genetically modified samples.
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Affiliation(s)
- Ewa Pobozy
- Department of Chemistry, Warsaw University, Warsaw, Poland
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Gassner AL, Rudaz S, Schappler J. Static coatings for the analysis of intact monoclonal antibody drugs by capillary zone electrophoresis. Electrophoresis 2013; 34:2718-24. [DOI: 10.1002/elps.201300070] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 06/12/2013] [Accepted: 06/12/2013] [Indexed: 01/28/2023]
Affiliation(s)
- Anne-Laure Gassner
- School of Pharmaceutical Sciences; University of Geneva, University of Lausanne; Geneva; Switzerland
| | - Serge Rudaz
- School of Pharmaceutical Sciences; University of Geneva, University of Lausanne; Geneva; Switzerland
| | - Julie Schappler
- School of Pharmaceutical Sciences; University of Geneva, University of Lausanne; Geneva; Switzerland
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Affiliation(s)
| | - Roberto Sebastiano
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”; Politecnico di Milano; Milano; Italy
| | - Attilio Citterio
- Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”; Politecnico di Milano; Milano; Italy
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Šolínová V, Poitevin M, Koval D, Busnel JM, Peltre G, Kašička V. Capillary electrophoresis in classical and carrier ampholytes-based background electrolytes applied to separation and characterization of gonadotropin-releasing hormones. J Chromatogr A 2012; 1267:231-8. [DOI: 10.1016/j.chroma.2012.07.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/16/2012] [Accepted: 07/19/2012] [Indexed: 10/28/2022]
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Pan Y, Treacy S, Gu X, Miller D, Burczynski F. Evaluation and Optimization of Capillary Zone Electrophoresis for Common Drugs of Forensic Interest in Aqueous Matrix. Canadian Society of Forensic Science Journal 2012. [DOI: 10.1080/00085030.2012.10757190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Zhang Z, Wang J, Hui L, Li L. Membrane-assisted capillary isoelectric focusing coupling with matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry for neuropeptide analysis. J Chromatogr A 2011; 1218:5336-43. [PMID: 21696746 DOI: 10.1016/j.chroma.2011.05.072] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 05/13/2011] [Accepted: 05/18/2011] [Indexed: 12/30/2022]
Abstract
Herein we report a highly efficient and reliable membrane-assisted capillary isoelectric focusing (MA-CIEF) system being coupled with MALDI-FTMS for the analysis of complex neuropeptide mixtures. The new interface consists of two membrane-coated joints made near each end of the capillary for applying high voltage, while the capillary ends were placed in the two reservoirs which were filled with anolyte (acid) and catholyte (base) to provide pH difference. Optimizations of CIEF conditions and comparison with conventional CIEF were carried out by using bovine serum albumin (BSA) tryptic peptides. It was shown that the MA-CIEF could provide more efficient, reliable and faster separation with improved sequence coverage when coupled to MALDI-FTMS. Analyses of orcokinin family neuropeptides from crabs Cancer borealis and Callinectes sapidus brain extracts have been conducted using the established MA-CIEF/MALDI-FTMS platform. Increased number of neuropeptides was observed with significantly enhanced MS signal in comparison with direct analysis by MALDI-FTMS. The results highlighted the potential of MA-CIEF as an efficient fractionation tool for coupling to MALDI MS for neuropeptide analysis.
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Liu Q, Tian J, Zhang C, Yang H, Liu Y, Qin W, Liu Z. Cationic poly(amidoamine) dendrimers as additives for capillary electroseparation and detection of proteins. Electrophoresis 2011; 32:1302-8. [DOI: 10.1002/elps.201000440] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 01/11/2011] [Accepted: 01/13/2011] [Indexed: 11/09/2022]
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12
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Tursen J, Wang A, Qin W. Electrophoretic separation of acidic and basic proteins in the presence of micromolar concentrations of an ionic liquid. Mikrochim Acta 2011; 174:63-71. [DOI: 10.1007/s00604-011-0599-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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13
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Salmanowicz BP. Identification and characterization of high-molecular-weight secalins from triticale seeds by capillary zone electrophoresis. Electrophoresis 2010; 31:2226-35. [DOI: 10.1002/elps.200900691] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Rambla-Alegre M, Peris-Vicente J, Esteve-Romero J, Capella-Peiró ME, Bose D. Capillary electrophoresis determination of antihistamines in serum and pharmaceuticals. Anal Chim Acta 2010; 666:102-9. [DOI: 10.1016/j.aca.2010.03.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 03/11/2010] [Accepted: 03/18/2010] [Indexed: 10/19/2022]
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Bachmann S, Vallant R, Bakry R, Huck CW, Corradini D, Bonn GK. CE coupled to MALDI with novel covalently coated capillaries. Electrophoresis 2010; 31:618-29. [DOI: 10.1002/elps.200900507] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Alahmad Y, Thuy Tran N, Duboeuf J, Grégoire A, Rancé I, Taverna M. CZE for glycoform profiling and quality assessment of recombinant human interleukin-7. Electrophoresis 2009; 30:2347-54. [DOI: 10.1002/elps.200800789] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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17
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Stutz H. Protein attachment onto silica surfaces - a survey of molecular fundamentals, resulting effects and novel preventive strategies in CE. Electrophoresis 2009; 30:2032-61. [DOI: 10.1002/elps.200900015] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Mandaji M, Rübensam G, Hoff RB, Hillebrand S, Carrilho E, Kist TL. Sample stacking in CZE using dynamic thermal junctions I. Analytes with low dpKa/dTcrossing a single thermally induced pH junction in a BGE with high dpH/dT. Electrophoresis 2009; 30:1501-9. [DOI: 10.1002/elps.200800584] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Koval D, Busnel J, Hlaváček J, Jiráček J, Kašička V, Peltre G. Evaluation of carrier ampholyte‐based capillary electrophoresis for separation of peptides and peptide mimetics. Electrophoresis 2008; 29:3759-67. [DOI: 10.1002/elps.200800193] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dušan Koval
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jean‐Marc Busnel
- Laboratoire Environnement et Chimie and Analytique, Ecole Supérieure de Physique et Chimie Industrielles, Paris, France
- Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Jan Hlaváček
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jiří Jiráček
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Václav Kašička
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Gabriel Peltre
- Laboratoire Environnement et Chimie and Analytique, Ecole Supérieure de Physique et Chimie Industrielles, Paris, France
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Ronda F, Rodríguez-nogales JM, Sancho D, Gómez BOYM. Multivariate optimisation of a capillary electrophoretic method for the separation of glutenins. Application to quantitative analysis of the endosperm storage proteins in wheat. Food Chem 2008; 108:287-96. [DOI: 10.1016/j.foodchem.2007.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Shaw BF, Schneider GF, Bilgiçer B, Kaufman GK, Neveu JM, Lane WS, Whitelegge JP, Whitesides GM. Lysine acetylation can generate highly charged enzymes with increased resistance toward irreversible inactivation. Protein Sci 2008; 17:1446-55. [PMID: 18451358 DOI: 10.1110/ps.035154.108] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This paper reports that the acetylation of lysine epsilon-NH3(+) groups of alpha-amylase--one of the most important hydrolytic enzymes used in industry--produces highly negatively charged variants that are enzymatically active, thermostable, and more resistant than the wild-type enzyme to irreversible inactivation on exposure to denaturing conditions (e.g., 1 h at 90 degrees C in solutions containing 100-mM sodium dodecyl sulfate). Acetylation also protected the enzyme against irreversible inactivation by the neutral surfactant TRITON X-100 (polyethylene glycol p-(1,1,3,3-tetramethylbutyl)phenyl ether), but not by the cationic surfactant, dodecyltrimethylammonium bromide (DTAB). The increased resistance of acetylated alpha-amylase toward inactivation is attributed to the increased net negative charge of alpha-amylase that resulted from the acetylation of lysine ammonium groups (lysine epsilon-NH3(+) --> epsilon-NHCOCH3). Increases in the net negative charge of proteins can decrease the rate of unfolding by anionic surfactants, and can also decrease the rate of protein aggregation. The acetylation of lysine represents a simple, inexpensive method for stabilizing bacterial alpha-amylase against irreversible inactivation in the presence of the anionic and neutral surfactants that are commonly used in industrial applications.
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Affiliation(s)
- Bryan F Shaw
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
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Abstract
Hydrochloric acid was investigated as a rinsing reagent to remove adsorbed proteins from linear polyacrylamide-coated capillaries for electrophoresis. Three model proteins were used, namely cytochrome c as a basic protein, beta-lactoglobulin as an acidic protein, and beta-casein as a more easily denaturing protein. In order to regenerate capillary surfaces, they have been rinsed for 5 min with 2 M hydrochloric acid, 5 min with water, and then 30 min with buffer after every tenth run. It was found important to perform this regeneration procedure on time. The obtained results show good repeatability of the apparent EOF mobility with percentage RSDs below 3% (n = 60) in various cases. These good results were mainly confirmed in long-term series with more than 200 runs each. Only very high concentrations (175 microM) of beta-lactoglobulin and beta-casein at pH 3.5 gave RSD% values above 5%. For these conditions, the further test of 85% m/m phosphoric acid as rinsing reagent showed a good repeatability of the apparent EOF mobilities as well.
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Piergiovanni AR. Extraction and separation of water-soluble proteins from different wheat species by acidic capillary electrophoresis. J Agric Food Chem 2007; 55:3850-6. [PMID: 17439145 DOI: 10.1021/jf063628n] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Optimization of protein extraction and a capillary zone electrophoresis method for water-soluble protein analysis in wheat is described. The optimal separation was obtained with a 50 microm i.d. x 27 cm (20 cm to detector) uncoated capillary filled with 0.1 M phosphoric acid/beta-alanine, pH 2.5, buffer containing urea (1 M), 0.05% (w/v) hydroxypropylmethylcellulose, and 20% (v/v) acetonitrile. Separation was carried out at 15 kV and 35 degrees C for 9 min. Extract stability was also investigated within 2 h from the extraction. Good visual peak parameters and a higher sensitivity can be obtained when 30% ethanol is used as an extraction medium. The method was successfully used to analyze extracts obtained from whole and refined meals of six Triticum spp. Moreover, the described methodology could be applied to the discrimination of species with different ploidy levels and to the detection of durum wheat adulteration, as well as to screen wheat collections for enzymes involved with the quality of wheat derivatives.
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Mendieta ME, Antonioli P, Righetti PG, Citterio A, Descroix S, Sebastiano R. Effect of barium tetraborate on the separation of tryptic digests of proteins by zone electrophoresis in uncoated capillaries. Electrophoresis 2006; 27:4016-24. [PMID: 16983636 DOI: 10.1002/elps.200600054] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A simple, fast, efficient and reproducible method for peptide separations in CZE is reported. It consists in running tryptic digests of peptides in an uncoated capillary, in a BGE composed of tetraborate as a buffering ion, in which the typical sodium counterion is substituted with barium. Efficient absorption of this divalent cation to ionized silanols and barium silicate precipitation seem to be able to shield effectively the silica surface from separands. This is demonstrated by the fact that, when tBa(2+) ions are present in solution (from pH 8.5 up to pH 11.0), the electroendoosmotic flow is reversed; such reversal being progressively higher at higher pH values, by up to a four-fold. Separations become progressively better at higher pH values, whereas at pH 11 in sodium tetraborate they are dramatically worsened. It is further hypothesized that the barium silicate layer further protects the silica surface against dissolution and corrosion which is quite substantial at pH 11.
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Affiliation(s)
- Martha Elena Mendieta
- Department of Chemistry, Materials and Engineering Chemistry, Politecnico di Milano, Milan, Italy
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Rodriguez-Nogales JM, Garcia MC, Marina ML. High-performance liquid chromatography and capillary electrophoresis for the analysis of maize proteins. J Sep Sci 2006; 29:197-210. [PMID: 16524093 DOI: 10.1002/jssc.200500308] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Methods for the analysis of maize proteins using HPLC and CE are reviewed. Most of the references cited in this review concern HPLC methods. Size-exclusion HPLC and especially RP-HPLC methods have been developed for characterization of normal and genetically modified maize, cultivar differentiation, and prediction of quality. Few CE methods for the analysis of maize proteins were found in the existing literature. Most of these methods focus on optimization of the separation of maize proteins using CZE and SDS-capillary gel electrophoresis.
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Corradini D, Bevilacqua L, Nicoletti I. Separation of Basic Proteins in Bare Fused-Silica Capillaries with Diethylentriamine Phosphate Buffer as the Background Electrolyte Solution. Chromatographia 2005. [DOI: 10.1365/s10337-005-0579-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
Capillary electrophoresis has been applied to the discrimination of 13 Vicia species, belonging to four sections of Vicia genus. The studied species necessitate of plant growing tests or DNA molecular markers to be distinguished being their seeds morphologically very similar. Alcoholic/saline extracts from dry cotyledons were separated in uncoated fused-silica capillary with iminodiacetic acid isolectric buffer containing hydroxypropylmethylcellulose and acetonitrile. The low intra-specific variation observed for 11 species, suggests that this approach is suitable to carry out species discrimination. Species-specific peaks were identified for V. articulata, V. atropurpurea, V. bithynica, V. benghalensis, V. disperma, V. ervilia, V. monantha, V. sativa and V. villosa. Conversely, V. lutea, V. melanops and V. peregrina, showing very similar electrophoregrams, require other methodological approaches to be discriminated. The discussed CE method appears to have a potential to be regarded as an alternative tool to identify some Vicia species being far less expensive and time consuming than plant growing tests and DNA molecular markers.
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Abstract
We describe a method for the simultaneous determination of the five fibrinopeptide forms derived from the thrombin-promoted activation of human fibrinogen by capillary zone electrophoresis (CZE). The fibrinopeptide mixture was first desalted by a solid-phase extraction (SPE) step. The analysis was performed in reversed polarity in a highly cross-linked polyethylene glycol (PEG)-coated capillary with UV-light absorption detection at 200 nm. Several parameters including buffer concentration and pH, presence of an organic modifier, temperature, and applied voltage, have been tested. The best separations were obtained within 20 min, utilizing a 20 mM sodium phosphate buffer without organic modifier, in the narrow 6.1-6.2 pH range, at 25 degrees C, with an applied voltage of 20 kV. Quantitative analysis is made possible by the use of sheep fibrinopeptide A as an internal standard to correct for both extraction and injection errors.
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Affiliation(s)
- Aldo Profumo
- S.C. Medicina Rigenerativa, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
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Abstract
The present mini-review summarizes the experience gathered by our group in developing different classes of novel quaternarized heterocyclic compounds able to modulate and reverse the electroendoosmotic flow (EOF) in a most peculiar manner. The first class comprises mono-salt compounds, with the determinant omega-iodoalkyl chains of different lengths (typically C4-C8), able to be adsorbed by silicas, at alkaline pH, and spontaneously alkylate ionised silanols, thus becoming covalently affixed to it. The second class is constituted by di-salt compounds, attached at the termini of an alkyl chain of variable lengths (here too, typically, C4-C8). This second class is unable to bind covalently silica surfaces, although, in thin-layer chromatography, it exhibits an extraordinary affinity for silica beads, contrary to the first one. On the basis of the strikingly different behaviour, structural rules are derived for the minimum requirements for general classes of amines to bind to silica walls and modify EOF. For compounds unable to bind covalently to the wall, the most important structural motif is two quaternary nitrogens spaced apart by a C4 chain: this seems to be the average distance (i.e., 0.8 nm) between two adjacent, ionized silanols for a snug fit. The other structural binding motif is the "hydrophobic decoration", i.e., the ratio of charged groups to alkyl residue in the various amines; amines with high levels of such alkane groups (i.e., with higher hydrophobicity), seem to bind more tenaciously to the wall, probably due to hydrophobic interaction not to the wall but among the amine derivatives themselves, when carpeting the silica.
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Affiliation(s)
- Pier Giorgio Righetti
- Department of Agricultural and Industrial Biotechnology, University of Verona, Strada Le Grazie 15, Verona 37134, Italy
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Righetti PG, Hamdan M, Antonucci F, Verzola B, Bossi A. Chapter 15 Electrophoresis of proteins and peptides. Chromatography 6th Edition - Fundamentals and Applications of Chromatography and Related Differential Migration Methods. Elsevier; 2004. pp. 633-68. [DOI: 10.1016/s0301-4770(04)80028-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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31
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Abstract
Covalent binding of reactive metabolites of drugs to proteins has been a predominant hypothesis for the mechanism of toxicity caused by numerous drugs. The development of efficient and sensitive analytical methods for the separation, identification, quantification of drug-protein adducts have important clinical and toxicological implications. In the last few decades, continuous progress in analytical methodology has been achieved with substantial increase in the number of new, more specific and more sensitive methods for drug-protein adducts. The methods used for drug-protein adduct studies include those for separation and for subsequent detection and identification. Various chromatographic (e.g., affinity chromatography, ion-exchange chromatography, and high-performance liquid chromatography) and electrophoretic techniques [e.g., sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional SDS-PAGE, and capillary electrophoresis], used alone or in combination, offer an opportunity to purify proteins adducted by reactive drug metabolites. Conventionally, mass spectrometric (MS), nuclear magnetic resonance, and immunological and radioisotope methods are used to detect and identify protein targets for reactive drug metabolites. However, these methods are labor-intensive, and have provided very limited sequence information on the target proteins adducted, and thus the identities of the protein targets are usually unknown. Moreover, the antibody-based methods are limited by the availability, quality, and specificity of antibodies to protein adducts, which greatly hindered the identification of specific protein targets of drugs and their clinical applications. Recently, the use of powerful MS technologies (e.g., matrix-assisted laser desorption/ionization time-of-flight) together with analytical proteomics have enabled one to separate, identify unknown protein adducts, and establish the sequence context of specific adducts by offering the opportunity to search for adducts in proteomes containing a large number of proteins with protein adducts and unmodified proteins. The present review highlights the separation and detection technologies for drug-protein adducts, with an emphasis on methodology, advantages and limitations to these techniques. Furthermore, a brief discussion of the application of these techniques to individual drugs and their target proteins will be outlined.
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Affiliation(s)
- Shufeng Zhou
- Department of Pharmacy, Faculty of Science, National University of Singapore, Science Drive 4, Singapore 117543, Singapore.
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Affiliation(s)
- Wei
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Gang Xue
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
| | - Edward S. Yeung
- Ames LaboratoryUSDOE and Department of Chemistry, Iowa State University, Ames, Iowa 50011
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Abstract
A multicomponent background electrolyte (BGE) was developed and its composition optimized using artificial neural networks (ANN). The optimal BGE composition was found to be 90 mM boric acid, 115 mM Tris, and 0.75 mM EDTA (pH 8.4). A separation voltage of 20 kV, 20 degrees C and detection at 210 nm were used. The method was applied to characterize several humic acids originating from various countries of the American continent: soil (Argentina), peat (Brazil), leonardite (Guatemala and Mexico) and coal (United States). Comparison with humic acids of International Humic Substances Society (IHSS) standard samples was also done. Well reproducible electropherograms showing a relatively high number of peaks were obtained. Characterization of the samples by elemental analysis and UV spectrophotometry was also done. In spite of the very different origins, the similarities between humic acids are high and by matrix assisted desorption/ionization-time of flight (MALDI-TOF)-mass spectrometry it was shown that most of the m/z patterns are the same in all humic acids. This means that humic acids of different origin have the same structural units or that they contain the same components.
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Affiliation(s)
- Maria de Lourdes Pacheco
- Department of Analytical Chemistry, Faculty of Science, Masaryk University, Brno, Czech Republic
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34
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Abstract
The capillary walls of fused-silica capillary electrophoresis (CE) columns were modified with a thin film of polyaniline (PANI), providing open-tubular columns with a stable coating containing aromatic groups and amine functionalities. Fast and efficient separations were observed for small bioactive peptides under acidic conditions on PANI-coated columns. The mechanism of separation is based on hydrophobic interactions between the analytes and the polymeric matrix. Good reproducibility was observed from run-to-run. Due to the simple derivatization procedure, method flexibility, the uniformity of the coating and its stability, conjugated polymers could find practical application in capillary zone electrophoresis (CZE) separations.
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Affiliation(s)
- Alessandra Bossi
- Department of Science and Technology, University of Verona, Verona, Italy.
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Abstract
The article gives a comprehensive review on the recent developments in the applications of high-performance capillary electromigration methods, including zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography and electrochromatography, to analysis, preparation and physicochemical characterization of peptides. The article presents new approaches to the theoretical description and experimental verification of electromigration behavior of peptides, and covers the methodological aspects of capillary electroseparations of peptides, such as strategy and rules for the rational selection of separation mode and experimental conditions, sample treatment, suppression of peptide adsorption to the inner capillary wall, new developments in individual separation modes and new designs of detection systems. Several types of applications of capillary electromigration methods to peptide analysis are presented: conventional qualitative and quantitative analysis for determination of purity, determination in biomatrices, monitoring of physical and chemical changes and enzymatic conversions, amino acid and sequence analysis and peptide mapping of proteins. Some examples of micropreparative peptide separations are given and capabilities of capillary electromigration techniques to provide important physicochemical characteristics of peptides are demonstrated.
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Affiliation(s)
- V Kasicka
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague.
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36
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Abstract
In this paper, capillary electrophoresis in clinical and forensic analysis is reviewed on the basis of the literature of 1999, 2000 and the first papers in 2001. An overview of progress relevant examples for each major field of application, namely (i) analysis of drug seizures, explosives residues, gunshot residues and inks, (ii) monitoring of drugs, endogenous small molecules and ions in biofluids and tissues, (iii) general screening for serum proteins and analysis of specific proteins (carbohydrate deficient transferrin, alpha1-antitrypsin, lipoproteins and hemoglobins) in biological fluids, and (iv) analysis of nucleic acids and oligonucleotides in biological samples, including oligonucleotide therapeutics, are presented.
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Affiliation(s)
- W Thormann
- Department of Clinical Pharmacology, University of Bern, Switzerland.
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Abstract
This review article with 223 references describes recent developments in capillary electrophoresis (CE) of proteins and covers papers published during last two years, from the previous review (V. Dolnik, Electrophoresis 1999, 20, 3106-3115) through Spring 2001. It describes the topics related to CE of proteins including modeling of the electrophoretic properties of proteins, sample pretreatment, wall coatings, improving selectivity, detection, special electrophoretic techniques, and applications.
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Affiliation(s)
- V Dolnik
- Molecular Dynamics, Sunnyvale, CA 94085, USA.
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Abstract
Capillary electrophoresis (CE) is an automated approach to electrokinetic separations that has had a deep impact in all fields of life sciences, including biomedical and biotechnological research and clinical and forensic practice. The present review highlights aspects of peptides and proteins separations, with particular emphasis on macromolecular analytes of biomedical interest. Among the various CE techniques available, a novel methodology is here illustrated consisting in separations in acidic, isoelectric buffers, which have the advantage of protonating the silica wall, thus minimizing interactions of proteinaceous material with the siliceous surface, while allowing delivery of high voltage gradients, due to their low conductivities. The review ends with applications of CE to the analysis of folding/unfolding/refolding/misfolding of proteins, a field which has deep implications in the biomedical arena, since it is connected to a host of disorders, such as prion protein diseases.
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Affiliation(s)
- P G Righetti
- Department of Agricultural and Industrial Biotechnologies, University of Verona, Strada Le Grazie No. 15, 37134 Verona, Italy.
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