Preparation and Identification of Angelica sinensis Polysaccharide-iron Complex

摘要

Angelica sinensis polysaccharide(ASP)was extracted from Angelica sinensis by boiling water.An Angelica sinensis polysaccharide-iron complex(APC)was prepared under the alkaline condition by adding a ferric chloride solution to the ASP solution.Then some identifiable properties of the complex were studied.The content of iron(III)in the complex was determined with iodometry.The thermal property,the microscopic structure,the spectral characteristics,and N,C,H contents of the complex were examined by a variety of techniques including DSC,TEM,IR,NMR,and elemental analysis.The content of iron(III)in the complex ranges from 10% to 40%.The DSC result shows that the melting point of the complex is about 450 deg C.The TEM result shows that the complex has an iron(III)core(beta-FeOOH core)linked by hydroxy and oxy bridges,with the polysaccharide chains attached to the surface of the core.The IR and NMR results also show that there is a beta-FeOOH core in the complex.The elemental analysis shows that the contents of N,C,H in the complex are,respectively,lower than those of N,C,H in ASP.All our studies indicate that the APC consists of a beta-FeOOH core surrounded by ASP.