Linear sweep voltammetric studies on the complex of alizarin red s with aloe polysaccharide and determination of aloe polysaccharide.

A new electrochemical method for the determination of aloe polysaccharide based on its interaction with alizarin red s was established on a pretreated glassy carbon electrode in pH 3.5 Britton-Robinson buffer solution by linear sweep voltammetry in this work. The decrease of the second order derivative linear sweep voltammetric reductive peak current of alizarin red s is in proportion to aloe polysaccharide concentration due to the formation of a complex between them in the range from 0.032 to 0.448μmolL(-1), and the detection limit is 0.0051μmolL(-1) (3σ). The binding ratio and the binding constant of the complex were calculated as 1:1 and 2.75×10(4), respectively. Different kinds of complex samples of aloe polysaccharide were detected satisfactorily by this method.