A novel diazoresin/poly(N‐vinyl aminobutyric acid) covalent capillary coating for the analysis of proteins by capillary electrophoresis

Abstract

A novel method for the preparation of covalently linked capillary coatings of poly(N-vinyl aminobutyric acid) (PVAA) obtained from hydrolyzed polyvinylpyrrolidone was demonstrated using photosensitive diazoresin (DR) as a coupling agent. A layer-by-layer self-assembled film of DR and PVAA based on ionic bonding was first fabricated on the inner wall of capillary, then ionic bonding was converted into covalent bonding after treatment with UV light through a unique photochemical reaction of DR. The covalently bonded coatings suppressed protein adsorption on the inner surface of the capillary, and thus a baseline separation of lysozyme, cytochrome c, BSA, amyloglucosidase, and myoglobin was achieved using CE. Compared with bare capillary or noncovalently bonded DR/PVAA coatings, the covalently linked DR/PVAA capillary coatings not only improved the CE separation performance for proteins, but also exhibited good stability and repeatability. Due to the replacement of the highly toxic and moisture-sensitive silane coupling agent by DR in the covalent coating preparation, this method may provide a green and easy way to make covalently coated capillaries for CE.

Sugar fractionation using surface-modified nanofiltration membranes

“…6, covalently linked capillary coating of PSS is prepared using the layer by layer self-assembly technique combined with photochemistry reactions. PSS coating based on ionic bonding was first assembled on the membrane surface by using photosensitive diazoresin (DR) as the coupling agent, and then the ionic bonding was converted into covalent bonding after treatment with UV light through a unique photochemistry reaction of DR [43][44][45]. Compared with uncrosslinked [PSS/PDADMAC] n PSS coating, the covalent PSS/DR coating has good stability and reproducibility.…”

Recent advances in protein analysis by capillary and microchip electrophoresis

“…44 The ionic bonding between PVAA and DR was converted into covalent bonding through UV-initiated cross-linking. The covalent coat showed good stability and repeatability (RSD% of EOF was < 0.9 run to run and < 3.6 capillary to capillary, n=5) and was applied for the separation of lysozyme, cytochrome c, amyloglucosidase, myoglobin, and BSA.…”

Recent trends in capillary electrophoresis for complex samples analysis: A review

“…Bing Yu and co‐workers have applied a layer‐by‐layer self‐assembling procedure to the synthesis of a covalently linked multilayered polymer coating film . The described procedure employs diazoresin (DR) as coupling agent in order to take advantage of its photosensitive properties.…”

“…As a final step, the capillary is exposed to 365 nm light in order to photochemically decompose the diazo‐groups in the DR, leading to a final covalently linked coating. This general procedure has been applied to obtain coatings of diverse nature by employing different polymeric coating agents as PEG and poly( N ‐vinyl aminobutyric acid) . The method has also been applied to the obtaining of DR—cyclodextrin dendrimers and DR—carboxyl fullerene .…”