title: Determination of the amylose-amylopectin ratio of starches by iodine-affinity capillary electrophoresis.
abstract: This paper describes the application of capillary electrophoresis to separate and quantify the main polysaccharide components, amylose and amylopectin, present in starch samples. The separation is based on the well-known affinity of these compounds to iodine. The starch components could be effectively separated in less than 7 min using an uncoated fused-silica 'bubble cell' capillary. The proposed method has been applied for the quantitative determination of the soluble amylose content and the ratio amylose-amylopectin in commercial starches. It is shown that the present method is reliable, gives detection limits in the order of 0.1 mg mL(-1), is faster than other methodologies reported in the literature, and can be easily applied to the analysis of different starches. In spite of differences in solubility of amylopectin from different sources, a reasonable estimate of the amylose-amylopectin ratio could be made. Additionally, it was shown that the resulting profiles obtained after hydrolysis with isoamylase and alpha-amylase can provide information on the structure of the starches studied.
authors.affiliation: Polymer-Analysis Group, Department of Chemical Engineering, University of Amsterdam, Nieuwe Achtergracht 166, NL-1018 WV Amsterdam, The Netherlands.
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Herrero-Martínez
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Schoenmakers
authors.forename: Wim Th
authors.initials: WT
authors.lastname: Kok
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D000688:Amylose / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D007454:Iodides / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D007454:Iodides; D000688:Amylose; D000687:Amylopectin