2005
Studies of proteins adsorption in polyethyleneimine coated capillaries in capillary zone electrophoresis
SPANILÁ, Miroslava; Jiří PAZOUREK a Josef HAVELZákladní údaje
Originální název
Studies of proteins adsorption in polyethyleneimine coated capillaries in capillary zone electrophoresis
Název česky
Studium adsorpce proteinů v polyethyleniminem koutovaných kapilárách v kapilární zónové elektroforéze
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Vydání
Pardubice, 11th International Symposium on Separation Sciences ISSS 2005. Book of Abstracts. s. 231-231, 2005
Nakladatel
Univerzita Pardubice
Další údaje
Jazyk
angličtina
Typ výsledku
Stať ve sborníku
Obor
10406 Analytical chemistry
Stát vydavatele
Česká republika
Utajení
není předmětem státního či obchodního tajemství
Označené pro přenos do RIV
Ano
Kód RIV
RIV/00216224:14310/05:00025070
Organizační jednotka
Přírodovědecká fakulta
ISBN
80-7194-771-7
Klíčová slova anglicky
capillary coating; polyethyleneimine; electroosmotic flow; protein adsorption
Změněno: 10. 12. 2008 16:00, Mgr. Miroslava Bittová, Ph.D.
V originále
The magnitude and the direction of electroosmotic flow (EOF) has fundamental influence to separation in capillary zone electrophoresis. Adsorption of proteins on the negative charged silica surface of uncoated capillaries can lead to analyte loss and to irreproducibility of analyses. Therefore, in biomolecules analyses, the inner surface modification of fused-silica capillaries is recommended. One of the used coating is polyethyleneimine (PEI): as a polycationic polymer it creates positively charged covalent coating on the capillary inner wall and hence minimizes the adsorption of basic proteins at acidic pH and maintains the electroosmotic flow stable [1]. In this work, the properties of PEI coated capillaries with respect to different background electrolytes are described. The changes of inner surface of the capillary were followed by electroosmotic flow measurement [2]. Several buffers commonly used in electrophoretic separations of proteins (MES, acetate, borate) were tested, but the main interest was taken into carboxylic acids as a buffers (citrate, malate, malonate, tartrate and succinate). Interesting behaviour of EOF in PEI coated capillaries was observed: the direction (and the value) depend on pKa of the background electrolyte and at certain pH it can reversibly change from positive to negative. With this knowledge the influence of ionic strength and pH of background electrolyte on the separation of basic proteins was studied. As a model, the standard protein mixture of cytochrome C, ribonuclease A and lysozyme in concentration of 0.25 mg/ml was chosen. Finally, the experimental conditions for humanin analyses were optimized.
Česky
The magnitude and the direction of electroosmotic flow (EOF) has fundamental influence to separation in capillary zone electrophoresis. Adsorption of proteins on the negative charged silica surface of uncoated capillaries can lead to analyte loss and to irreproducibility of analyses. Therefore, in biomolecules analyses, the inner surface modification of fused-silica capillaries is recommended. One of the used coating is polyethyleneimine (PEI): as a polycationic polymer it creates positively charged covalent coating on the capillary inner wall and hence minimizes the adsorption of basic proteins at acidic pH and maintains the electroosmotic flow stable [1]. In this work, the properties of PEI coated capillaries with respect to different background electrolytes are described. The changes of inner surface of the capillary were followed by electroosmotic flow measurement [2]. Several buffers commonly used in electrophoretic separations of proteins (MES, acetate, borate) were tested, but the main interest was taken into carboxylic acids as a buffers (citrate, malate, malonate, tartrate and succinate). Interesting behaviour of EOF in PEI coated capillaries was observed: the direction (and the value) depend on pKa of the background electrolyte and at certain pH it can reversibly change from positive to negative. With this knowledge the influence of ionic strength and pH of background electrolyte on the separation of basic proteins was studied. As a model, the standard protein mixture of cytochrome C, ribonuclease A and lysozyme in concentration of 0.25 mg/ml was chosen. Finally, the experimental conditions for humanin analyses were optimized.
Návaznosti
| GA305/03/1100, projekt VaV |
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