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001-es BibID:	BIBFORM116213
035-os BibID:	(WoS)001104988800001 (Scopus)85178183698
Első szerző:	Farsang Róbert
Cím:	Capillary Zone Electrophoresis of 8-Aminopyrene-1,3,6-trisulfonic Acid Labeled Carbohydrates with Online Electrokinetic Sample Cleanup / Farsang Robert, Hogyor Kinga, Jarvas Gabor, Guttman Andras
Dátum:	2023
ISSN:	0003-2700
Megjegyzések:	Capillary electrophoresis is one of the frequently used separation techniques for the analysis of complex carbohydrates. Since sugars lack chromophore or fluorophore groups, their capillary electrophoresis analysis usually requires tagging by a charged fluorophore. To speed up the derivatization reaction, a large excess of the labeling reagent is typically used; therefore, a purification step is necessary prior to CE analysis using the industry standard low-pH gel-buffer system. In addition to representing an extra sample preparation step with the associated labor and cost, the purification process also holds the risk of losing some of the sample components. In this paper we introduce an online electrokinetic sample cleanup process with electroosmotic flow (EOF)-assisted separation in a bare fused silica capillary using alkaline pH background electrolyte and normal polarity separation voltage. 8-Aminopyrene-1,3,6-trisulfonic acid (APTS)-labeled maltooligosaccharides were analyzed first to understand the complex effect of the downstream EOF and the counter current electromigration of the sample components including the labeling dye. The use of 150 mM caproic acid?253 mM Tris (pH 8.1) running buffer facilitated the entrance of the sample components of interest into the separation capillary, while the excess labeling reagent was excluded and, therefore, did not interfere with the detection. The alkaline caproic acid?Tris running buffer was then applied to the N-glycome analysis of human serum samples, showing excellent separation performance, and more importantly, the extra sample purification step was not required.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Capillary electrophoresis Carbohydrates Electroosmosis Labeling Polarity
Megjelenés:	Analytical Chemistry. - 95 : 45 (2023), p. 16459-16464. -
További szerzők:	Hogyor Kinga Járvás Gábor (1982-) (vegyészmérnök) Guttman András (1954-) (vegyészmérnök)
Pályázati támogatás:	DE TUDFIN Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM115940
035-os BibID:	(cikkazonosító)115812 (scopus)85175539824
Első szerző:	Farsang Róbert
Cím:	Purification free N-glycan analysis by capillary zone electrophoresis : Hunt for the lost glycans / Farsang Robert, Jarvas Gabor, Guttman Andras
Dátum:	2024
ISSN:	0731-7085
Megjegyzések:	Capillary gel electrophoresis is a widely used method for rapid separation of fluorophore labeled carbohydrates. Even though, many publications conferred about this popular technique, no report yet investigated the possible sample losses during the purification process of the fluorophore labeling reaction mixture. In the present work, normal polarity capillary zone electrophoresis separation mode was applied to take advantage of the opposite migration directions of the electroosmotic flow and the negatively charged sample components using Tris- hexanoic acid running buffer at basic pH. For purification free oligosaccharide analysis, the separation parameters were designed in such a way that the triple charged labeling reagent of aminopyrenetrisulfonate (APTS) could not enter the separation capillary in contrary to the labeled sample components of interest, therefore, the APTS did not have to be removed before analysis. The method was used to show electrophoretic profile differences possibly caused by the cleanup process that was immediately apparent by comparing the electropherograms of the purified and non-purified APTS labeled maltooligosaccharides. Furthermore, qualitative and quantitative N-glycosylation profile alterations were revealed during CZE separation of the fluorophore labeling reaction mixtures before and after purification along with the analysis of the consecutively used washing solutions for the well characterized standard glycoproteins of IgG, ribonuclease B and fetuin.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk N-glycans Capillary zone electrophoresis Purification Sample loss
Megjelenés:	Journal Of Pharmaceutical And Biomedical Analysis. - 238 (2024), p. 1-5. -
További szerzők:	Járvás Gábor (1982-) (vegyészmérnök) Guttman András (1954-) (vegyészmérnök)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM106794
035-os BibID:	(cikkazonosító)333 (scopus)85141755492 (wos)000881482500001
Első szerző:	Farsang Róbert
Cím:	Ultrahigh-Sensitivity Capillary Electrophoresis Analysis of Trace Amounts of Nitrate and Nitrite in Environmental Water Samples / Farsang Robert, Kovacs Zsofia, Jarvas Gabor, Guttman Andras
Dátum:	2022
ISSN:	2297-8739
Megjegyzések:	The role of nitrite (NO2?) and nitrate (NO3?) is essential in the global nitrogen cycle. Monitoring their concentration in environmental and industrial aqueous samples, surface water, soil, food and agricultural products are of high importance. Especially, the effect of anthropogenic emission, i.e., intensified agriculture is essential due to the overuse of nitrogen, phosphorus and potassium fertilizers. The most widely utilized methods for nitrate and nitrite determination are colorimetry, potentiometry, UV absorption and liquid chromatography. Among them, UV spectroscopy is the most frequently used technique due to the fact of its versatility and simplicity. However, there are industrial and academic needs to develop new methods to overcome some drawbacks of the currently used techniques such as an inadequate limit of detection and potential interferences with organic compounds in the sample. In this paper, we report on the development of a new analytical method based on capillary electrophoresis separation with high-sensitivity UV detection, capable of measuring trace concentrations of nitrite and nitrate well below the current limits of UV spectroscopy methods. During the development process special attention was paid to practical aspects, i.e., the method was tested to quantify nitrate and nitrite in various surface water samples.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Separations. - 9 : 11 (2022), p. 1-7. -
További szerzők:	Kovács Zsófia Járvás Gábor (1982-) (vegyészmérnök) Guttman András (1954-) (vegyészmérnök)
Pályázati támogatás:	RRF 2.3.1-21-2022-00008 Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM106825
035-os BibID:	(cikkazonosító)8192 (scopus)85143597041 (wos)000896340300001
Első szerző:	Torok Rebeka
Cím:	The Effect of Sample Glucose Content on PNGase F-Mediated N-Glycan Release Analyzed by Capillary Electrophoresis / Torok Rebeka, Auer Felicia, Farsang Robert, Jona Eszter, Jarvas Gabor, Guttman Andras
Dátum:	2022
ISSN:	1420-3049
Megjegyzések:	Protein therapeutics have recently gained high importance in general health care along with applied clinical research. Therefore, it is important to understand the structure?function relationship of these new generation drugs. Asparagine-bound carbohydrates represent an important critical quality attribute of therapeutic glycoproteins, reportedly impacting the efficacy, immunogenicity, clearance rate, stability, solubility, pharmacokinetics and mode of action of the product. In most instances, these linked N-glycans are analyzed in their unconjugated form after endoglycosidase-mediated release, e.g., PNGase F-mediated liberation. In this paper, first, N-glycan release kinetics were evaluated using our previously reported in-house produced 6His-PNGase F enzyme. The resulting deglycosylation products were quantified by sodium dodecyl sulfate capillary gel electrophoresis to determine the optimal digestion time. Next, the effect of sample glucose content was investigated as a potential endoglycosidase activity modifier. A comparative Michaelis-Menten kinetics study was performed between the 6His-PNGase F and a frequently employed commercial PNGase F product with and without the presence of glucose in the digestion reaction mixture. It was found that 1 mg/mL glucose in the sample activated the 6His-PNGase F enzyme, while did not affect the release efficiency of the commercial PNGase F. Capillary isoelectric focusing revealed subtle charge heterogeneity differences between the two endoglycosidases, manifested by the lack of extra acidic charge variants in the cIEF trace of the 6His-PNGase F enzyme, which might have possibly influenced the glucose-mediated enzyme activity differences.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Molecules. - 27 : 23 (2022), p. 1-8. -
További szerzők:	Auer, Felicia Farsang Róbert Jóna Eszter Járvás Gábor (1982-) (vegyészmérnök) Guttman András (1954-) (vegyészmérnök)
Pályázati támogatás:	UNKP-22-3-I Egyéb
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