Detection of bovine whey proteins by on-column derivatization capillary electrophoresis with laser-induced fluorescence monitoring

Benito, I; Marina, ML; Saz, JM; Diez-Masa, JC

HERO ID

1491905

Reference Type

Journal Article

Year

1999

Language

English

PMID

10360330

HERO ID 1491905
In Press No
Year 1999
Title Detection of bovine whey proteins by on-column derivatization capillary electrophoresis with laser-induced fluorescence monitoring
Authors Benito, I; Marina, ML; Saz, JM; Diez-Masa, JC
Journal Journal of Chromatography A
Volume 841
Issue 1
Page Numbers 105-114
Abstract 1-Anilinonaphthalene-8-sulfonic acid (1,8-ANS), 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid (bis-ANS) and 2-(p-toluidino)naphthalene-6-sulfonic acid (2,6-TNS) were evaluated as additives in different buffers for the detection of bovine whey proteins using laser-induced fluorescence (LIF) monitoring in capillary electrophoresis (CE). These N-arylaminonaphthalene sulfonates furnish a large fluorescence emission when associated to some proteins whereas their emission in aqueous buffers, such as those used in CE separations, is very small. To select the best detection conditions, the fluorescence of these probes was first compared using experiments carried out in a fluorescence spectrophotometer. Using bovine serum albumin (BSA) as a model protein, it was demonstrated that 2-(N-cyclohexylamino)ethanesulfonic acid (CHES) buffer (pH 8 and pH 10.2) and the fluorescent probe 2,6-TNS gave rise to the highest increase in fluorescence for BSA. When the composition of these separation buffers was optimized for the electrophoretic separations, CHES buffer, pH 10.2 was chosen as the most suitable buffer to detect bovine whey proteins. The limit of detection obtained for some whey proteins in CE separations was about 6.10(-8) M for BSA, 3.10(-7) M for beta-lactoglobulin A (beta-LGA), 3.10(-7) M for beta-lactoglobulin B (beta-LGB), and 3.10(-6) M for alpha-lactalbumin (alpha-LA). These detection limits were compared to those achieved using UV detection under the same separation conditions. The results showed that the detection limits of BSA, beta-LGA and beta-LGB were twice as good using LIF than with UV detection. However, the limit of detection for alpha-LA was better when UV was used. The applicability of LIF detection to CE separation of whey proteins in bovine milk samples was also demonstrated. (C) 1999 Elsevier Science B.V. All rights reserved.
Doi 10.1016/S0021-9673(99)00272-1
Pmid 10360330
Wosid WOS:000080243000010
Url https://www.scopus.com/inward/record.uri?eid=2-s2.0-0032947040&doi=10.1016%2fS0021-9673%2899%2900272-1&partnerID=40&md5=b84348ab62c0ea2a3c6c6a1ebdfa9985
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000080243000010
Is Public Yes
Language Text English
Keyword whey; derivatization; electrophoresis; proteins