Open tubular capillary electrochromatography: Technique for oxidation and interaction studies on human low-density lipoproteins - Analytical Methods & Tools for Lyophilization

Open tubular capillary electrochromatography: Technique for oxidation and interaction studies on human low-density lipoproteins
Engineering Village 2
2006 Elsevier Inc.
Accession number: 06189858629

Title: Open tubular capillary electrochromatography: Technique for oxidation and interaction studies on human low-density lipoproteins

Authors: Kuldvee, Ruth; D'ulivo, Lucia; Yohannes, Gebrenegus; Lindenburg, Petrus W.; Laine, Minna; Oorni, Katariina; Kovanen, Petri; Riekkola, Marja-Liisa

Author affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki, FIN-00014, Helsinki, Finland

Serial title: Analytical Chemistry

Abbreviated serial title: Anal. Chem.

Volume: v 78

Issue: n 8

Issue date: Apr 15 2006

Publication year: 2006

Pages: p 2665-2671

Language: English

ISSN: 0003-2700

CODEN: ANCHAM

Document type: Journal article (JA)

Publisher: American Chemical Society, Columbus, OH 43210-3337, United States

Abstract: A novel, open tubular capillary electrochromatographic method was developed for the in vitro oxidation of low-density lipoprotein (LDL) particles. Low-density lipoprotein particles with molar mass of [similar to] 2.5 MDa yielded a stable stationary phase at temperatures 25 and 37 ?C and at pH values from 3.2 to 7.4. The quality of the coatings was not influenced by variations in the LDL concentration in the coating solutions (within the range of 2-0.015 mg/mL) with the coating procedure used in the study. Radio-labeled LDL stationary phases and scanning electron microscopy, employed to shed light on the location and coating density of LDL particles on the inner surface of the capillary wall, confirmed the presence of an LDL monolayer and almost 100% coating efficiency (99 ? 8%). In addition, the radioactivity measurements allowed estimation of the amount of LDL present in a single capillary coating. Capillaries coated with human LDL particles were submitted to different oxidative conditions by changing the concentration of the oxidant (CuSO4), oxidation time, pH value, and temperature. The oxidation procedure was followed with electroosmotic flow mobility, which served as an indicator of the increase in total negative charges of LDL coatings, and by asymmetrical field flow fractionation, which measured the changes in size of the lipoprotein particles. The results indicated that oxidation of LDL was progressing with increasing time, temperature, and concentration of the oxidant as expected. The oxidation process was faster around neutral pH values (pH 6.5-7.4) and inhibited at acidic pH values (pH 5.5 and lower). ? 2006 American Chemical Society.

Number of references: 33

Ei main heading: Chromatographic analysis

Ei controlled terms: Capillarity - Oxidation - Proteins - Coating techniques - Scanning electron microscopy - pH

Uncontrolled terms: Electrochromatography - Low-density lipoprotein (LDL) particles - Coating efficiency

Ei classification codes: 801 Chemistry - 631.1 Fluid Flow, General - 802.2 Chemical Reactions - 804.1 Organic Compounds - 813.1 Coating Techniques - 741.1 Light/Optics - 801.1 Chemistry, General

Treatment: Experimental (EXP)

DOI: 10.1021/ac052006i

Database: Compendex

Compilation and indexing terms, ? 2006 Elsevier Inc. All rights reserved
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