Abstract:In this study, corn starch was used as the raw material, ethylenediamine and o-phenylenediamine were used as the amination reagents, four amino starches were synthesized by two modification methods, crosslinking-etherificationamination, and crosslinking-oxidation-amination, and their structural and functional properties were compared. It was found that the amino starch prepared through introducing o-phenylenediamine via crosslinking-oxidation-amination had the highest nitrogen content (5.97%) and amino content (3.07%), smooth particle/granular appearance, relatively high crystallinity (5.43%) and solubility (11.31%), relatively high starch chain decomposition temperature (220 ℃) and short-range ordering (0.63), and the highest DPPH• and ABTS+• scavenging efficiencies within 1 h (27.90% and 58.12%, respectively). The amino starch introduced with ethylenediamine via crosslinking-oxidation-amination had the highest crystallinity (6.02%) and solubility (91.45%), but the lowest starch chain decomposition temperature (170 ℃) and short-range order (0.46). In addition, blocklike structure was generated in this amino starch. The granular structure of the amino starch synthesized by the cross-linking-etherification-amination method was seriously damaged, with its crystalline structure disappearing completely, and solubility and antioxidant capacity being poor. In summary, the amino starch with o-phenylenediamine introduced via cross-linkingoxidation-amination have excellent structural and functional properties, and high potential for drug loading and heavy metal adsorption. The above results provide a certain reference for the application development of amino starches.
