Separation of cationic polymer particles and characterization of avidin‐immobilized particles by capillary electrophoresis

Abstract

Cationic polymer microparticles have received much attention especially in the field of biotechnology, such that their analysis and separation have become important. So far, the separation of cationic polymer particles with different size using CE has not been achieved and the cationic particles migrated as if they are negatively charged, probably due to electrostatic interaction between capillary wall and cationic polymer particles. In this paper, the separation of cationic polymer microparticles by CE was investigated in detail. The separation of cationic particles with different size was achieved in CE by taking into account the interaction between sample particles and the inner surface of capillaries. By employing a poly(vinyl alcohol)-coated capillary, a better size separation of amine-modified latex particles was obtained compared to a Polybrene-coated capillary. It was elucidated that the composition, concentration, and pH of the background solution were also important factors in the separation of colloidal particles to avoid the surface adsorption and the characteristic aggregation of polymer particles. Furthermore, the CE analysis was applied to the characterization of cationic protein-immobilized particles.

Capillary electrophoresis of proteins 2005–2007

“…CE was used to characterize acid phosphatase from Spirodella oligorrhiza [221], polyanion-protein complexes [222], dynamics of proteinase activation [223], proteins from Spirulina platensis microalga [224,225], F5cys-MP-PEG(2000)-DPSE protein-lipopolymer [226], basic proteins immobilized on polymer particles [227], RNA interference with sialidase [228], and combitorial peptide libraries in an assay of botulinum neurotoxin A [229].…”

Separation enhancement in pinched flow fractionation

“…The separation in the two types of devices were compared and an amplification in the separation of up to 70% was achieved. Numerical [3][4][5][6][7][8][9][10][11][12][13][14] Pinched flow fractionation ͑PFF͒ is a microchip based size separation technique for nanometer to micrometer sized particles relying on a laminar flow sheet. The method was first demonstrated by Yamada et al, 15 where 15 and 30 m polystyrene microspheres were separated.…”

Application of capillary zone electrophoresis for separation of water‐soluble gold monolayer‐protected clusters

“…For instance, it has been employed to separate Au [32,33,35,38,39,43], Ag [40,42], Au/Ag (core/ shell) [46], silicate nanoparticles [37], latex and polystyrene particles [29,30,36,44], and other metal oxides particles [31,34]. However, most of them were focused on the separation of larger core nanoparticles (diameter .5 nm) [29-34, 36-42, 44, 46] rather than MPCs, or the mixture [29-31, 34, 36, 37, 41]/two-component mixture [38,39,44,47] of commercial available nanoparticles rather than real sample of polydisperse product of nanoparticles, or separation of a polydisperse product of nanoparticle with poor resolution [32,33,35,[40][41][42]. In addition, the migration order of nanoparticles in CZE with bare capillary in some reports is quite contradicting whilst some claimed that the earlier-migrating peak was the larger core-size nanoparticles [32,33,36] and others suggested it was the smaller ones [29, 30, 37-39, 41, 42, 46, 47].…”