Comparison of three modifications of fused‐silica capillaries and untreated capillaries for protein profiling of maize extracts by capillary electrophoresis

Abstract

In this work, capillary electrophoresis was applied to protein profiling of fractionated extracts of maize. A comparative study on the application of uncoated fused-silica capillaries and capillaries modified with hydroxypropylmethylcellulose, ω-iodoalkylammonium salt and a commercially available neutral capillary covalently coated with polyacrylamide is presented. The coating stability, background electrolyte composition, and separation efficiency were investigated. It was found that for zeins separation, the most stable and efficient was the capillary coated with polyacrylamide. Finally, the usefulness of these methods was studied for the differentiation of zein fraction in transgenic and nontransgenic maize. Zeins extracted from maize standards containing 0 and 5% m/m genetic modification were successfully separated, but slight differences were observed in terms of the zein content. Albumin and globulin fractions were analyzed with the use of unmodified fused-silica capillary with borate buffer pH 9 and the capillary coated with polyacrylamide with phosphate buffer pH 3. In the albumin fraction, additional peaks were found in genetically modified samples.

Improving repeatability of capillary electrophoresis—a critical comparison of ten different capillary inner surfaces and three criteria of peak identification

“…On the other hand, the use of any type of coating significantly elevates the cost of analysis. The direct comparisons of various types of capillary modifications are rarely performed [27, 29, 33]. On that account, there is still little known about advantages and predispositions of the given capillary types in regard to the particular types of methods and experimental conditions, and this hinders their critical evaluation and selection.…”

Recent advances in protein analysis by capillary and microchip electrophoresis

“…40 The authors systematically compared the analytical performance of hydroxypropylmethylcellulose (HPMC) coated capillaries, polyacrylamide (PAA) coated capillaries (commercially available), and capillaries modified with 1-(4-iodobutyl) 4-aza- 1-azoniabicyclo[2,2,2]octane iodide (M7C4I). The authors reported that the highest separation efficiency and repeatability were obtained with the PAA capillary.…”

Characterization and Study of Transgenic Cultivars by Capillary and Microchip Electrophoresis

“…A common approach in CE to prevent protein adsorption is to coat the inner capillary wall with surface coating agents. Pobozy et al evaluate the performance of various capillary coatings for the profiling of fractionated protein extracts from maize samples [ 38 ]. Three coatings were tested, including dynamic (hydroxypropylmethylcellulose) and static (polyacrylamide and ω-iodoalkylammonium) coatings.…”