New multilayer coating using quaternary ammonium chitosan and κ-carrageenan in capillary electrophoresis: Application in fast analysis of betaine and methionine

• Published in: Talanta (Oxford) 2014-06, Vol.123, p.45-53
• Main Authors: Vitali, Luciano, Della Betta, Fabiana, Costa, Ana Carolina O., Vaz, Fernando Antonio Simas, Oliveira, Marcone Augusto Leal, Pereira Vistuba, Jacqueline, Fávere, Valfredo T., Micke, Gustavo A.
• Format: Article
• Language: English
• Subjects: Betaine; Betaine - analysis; Betaine - chemistry; Betaines; Capillarity; Capillary electrophoresis; Carbohydrate Sequence; Carrageenan - chemistry; Chitosan; Chitosan - analogs & derivatives; Chitosan - chemistry; Chromatography, Liquid - methods; Coating; Electrolytes; Electroosmosis; Electrophoresis; Electrophoresis, Capillary - methods; Fast method; Hydrogen-Ion Concentration; Methionine; Methionine - analysis; Methionine - chemistry; Molecular Sequence Data; Molecular Structure; Multilayer coating; Multilayers; Pharmaceutical formulations; Quaternary Ammonium Compounds - chemistry; Reproducibility of Results; Statistical methods; Tandem Mass Spectrometry - methods; Time Factors
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2014.01.047

The aim of this study was to develop a new multilayer coating with crosslinked quaternary ammonium chitosan (hydroxypropyltrimethyl ammonium chloride chitosan; HACC) and κ-carrageenan for use in capillary electrophoresis. A new semi-permanent multilayer coating was formed using the procedure developed and the method does not require the presence of polymers in the background electrolyte (BGE). The new capillary multilayer coating showed a cathodic electroosmotic flow (EOF) of around 30×10−9m2V−1s−1 which is pH-independent in the range of pH 2 to 10. The enhanced EOF at low pH obtained contributed significantly to the development of a fast method of separation. The multilayer coating was then applied in the development of a fast separation method to determine betaine and methionine in pharmaceutical formulations by capillary zone electrophoresis (CZE). The BGE used to determine the betaine and methionine concentrations was composed of 10mmolL−1 tris(hydroxymethyl) aminomethane, 40mmolL−1 phosphoric acid and 10% (v/v) ethanol, at pH 2.1. A fused-silica capillary of 32cm (50µm ID×375µm OD) was used in the experiments and samples and standards were analyzed employing the short-end injection procedure (8.5cm effective length). The instrumental analysis time of the optimized method was 1.53min (approx. 39 runs per hour). The validation of the proposed method for the determination of betaine and methionine showed good linearity (R2>0.999), adequate limit of detection (LOD