Dynamic Cross-Linking Effect of Mg2+ To Enhance Sieving Properties of Low-Viscosity Poly(vinylpyrrolidone) Solutions for Microchip Electrophoresis of Proteins

We report a dynamic cross-linking effect of Mg2+ that enhances the sieving properties of low-viscosity poly(vinylpyrrolidone) (PVP) solutions. A low-viscosity PVP solution was applied to nondenaturing microchip electrophoresis of protein samples using microchips made of poly(methyl methacrylate). Th...

Full description

Saved in:
Bibliographic Details
Published in:Analytical chemistry (Washington) 2008-01, Vol.80 (1), p.312-316
Main Authors: Mohamadi, Mohamad Reza, Kaji, Noritada, Tokeshi, Manabu, Baba, Yoshinobu
Format: Article
Language:English
Subjects:
Analytical chemistry
Carbonic Anhydrases - chemistry
Chemistry
Chromatographic methods and physical methods associated with chromatography
Cross-Linking Reagents - chemistry
Electrophoresis, Microchip - methods
Electrophoretic Mobility Shift Assay
Exact sciences and technology
Glucan 1,4-alpha-Glucosidase - chemistry
Humans
Lactalbumin - chemistry
Magnesium Chloride - chemistry
Other chromatographic methods
Povidone - chemistry
Protein Denaturation
Proteins - chemistry
Proteins - isolation & purification
Serum Albumin - chemistry
Solutions
Trypsin Inhibitors - chemistry
Viscosity
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We report a dynamic cross-linking effect of Mg2+ that enhances the sieving properties of low-viscosity poly(vinylpyrrolidone) (PVP) solutions. A low-viscosity PVP solution was applied to nondenaturing microchip electrophoresis of protein samples using microchips made of poly(methyl methacrylate). The separation resolution of nondenatured protein markers in 1.8% PVP solution was improved by adding 1−20 mM MgCl2. We studied the effect of the ratio of cross-linking agent on mobility of protein samples and showed that protein retardation (ln μ/μ0) is correlated with the ratio of cross-linking agent to PVP ([c Mg 2+ /c PVP]) as ln μ/μ0 = A‘[c Mg 2+ /c PVP] b ‘. A‘ was related to the protein radius (R), and b‘ was found to be 0.72 for proteins with R = 2.4 nm and 0.82 for proteins with R = 1.85 nm. A structural study of PVP in semidilute solutions using dynamic light scattering showed that incremental increases of Mg2+ ion concentration from 5 to 20 mM in 1.8% PVP solution increased the hydrodynamic radius of PVP polymers by 20%.
ISSN:0003-2700
1520-6882
DOI:10.1021/ac701974u