Characterization of poly(4-vinylpyridine 1-oxide) by free-solution capillary electrophoresis and micellar electrokinetic chromatography

✍ Scribed by Miriam Beneito-Cambra; José M. Herrero-Martínez; Guillermo Ramis-Ramos

• Book ID: 102188523
• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 353 KB
• Volume: 29
• Category: Article
• ISSN: 0173-0835
• DOI: 10.1002/elps.200800118

✦ Synopsis

Abstract

The migration characteristics of poly(4‐vinylpyridine 1‐oxide) (PVP‐NO) in phosphate buffers of acidic pH (20 mM H~3~PO~4~ or NaH~2~PO~4~) have been studied using both free‐solution capillary electrophoresis (FSCE) and MEKC. To inhibit adsorption, 250 mM o‐phosphoethanolamine (2‐aminoethyl dihydrogen phosphate) was used. In FSCE, PVP‐NO showed a narrow peak and a broader band, both having anionic behavior. These peak and band were attributed to the free and aggregated or micellized PVP‐NO forms, respectively. According to surface tension measurements, the CMC of SDS in the BGE was 1.8 and 0.48 mM in the absence and in the presence of 1000 µg/mL PVP‐NO, respectively, and the association of the polymer with SDS was completed at 9.7 mM SDS. Using MEKC, a narrow peak and a broader band also appeared at SDS concentrations of ca. 1 mM, and their intensity increased with the SDS concentration. These peak and band were attributed to the formation of mixed micelles constituted by both free PVP‐NO/SDS and aggregated PVP‐NO/SDS, respectively. The determination of PVP‐NO by FSCE in commercial additives for laundry was demonstrated.