Simple method for the preparation of highly efficient polymer‐coated capillary electrophoresis columns

Abstract

Abstract.A simple method for the preparation of polymer-coated fused silica capillary columns for electrophoresis is presented. It is shown that the static coating technique used in GC and SFC can be conveniently utilized for the preparation of highly efficient capillary electrophoresis columns. In this method, the coating solution contains appropriate proportions of three ingredients: a polymer, a surface derivatization reagent, and a crosslinking reagent dissolved in a suitable low-boiling solvent. After coating, the column is subjected to heat treatment to immobilize the polymer film. Simplicity, rapidity, high column efficiency, batch-to-batch and run-to-run reproducibility, and long column life-time are advantageous features of the new method. Column efficiencies of as high as 1.2 million theoretical plates were achieved for cytochrome c on a 96 cm long Ucon 75 H-90,000 coated column. Efficient electrophoretic separation of five cytochrome c proteins was achieved on a Superox 4 coated column. The possibility of CE separation of histones on the new columns was also explored.

Effect of buffer, electric field, and separation time on detection of aptamer‐ligand complexes for affinity probe capillary electrophoresis

“…In an attempt to further improve peak shapes for the complexes, capillaries coated with polyacrylamide (method used described in [27]) were used for both the IgE and thrombin assays. For these experiments, all other conditions were the same as for the TGK buffer at pH 8.4 described above.…”

Negatively charged sol‐gel column with stable electroosmotic flow for online preconcentration of zwitterionic biomolecules in capillary electromigration separations

“…Hjerten [25] used a neutral polymer (methylcellulose) to coat a fused silica capillary to suppress EOF. Other neutral polymers used as coating materials include poly(methylglutamate) (PMG) [26], poly(vinyl alcohol) (PVA) [27], polyethylene glycols (PEG) [28], and Ucon [29,30]. Depending on the desired direction of EOF and the properties of analytes, either positively or negatively charged coatings have been used [31 -37].…”

DNA capillary electrophoresis using poly(vinyl alcohol). I. Inner capillary coating

“…Incapillary polymerization of VAc and subsequent hydrolysis with NaOH have been carried out to generate a coating of PVAL with 2Si-C2 bonding. In comparison with similar approaches as reported in the literature by using the Grignard reaction and in-capillary polymerization of acrylamide [17][18][19], the present new coating method that generated the 2Si-C2 bonding with PVAL could be more advantageous because of their improved alkaline resistance. Figure 2 shows typical CE for dsDNA using PVAL (M r 25 000; DH = 88 mol%) as a medium polymer and using three capillaries coated by the three distinct coating methods: nonmodified PVAL as a control (Fig.…”

“…One of the groups has reported a result of "surprisingly weak EOF at pH 12 or higher in bare capillaries", but this phenomenon has not always been observed in their succeeding experiments, according to one of the authors (Klepárník, personal communication). Other groups have reported a new coating method with improved hydrolytic stability using the Grignard reaction [17][18][19], where the 2Si-C2 bonding is generated instead of the usual 2Si-O-Si2 bonding [20], but the coated polymer, PAM, is potentially hydrolysable.…”