壳聚糖与茜素红相互作用的电化学研究

生物活性大分子蛋白质、DNA及多糖等与小分子探针间的相互作用及其机理是近年来化学、临床医学及生命科学中研究的热点之一，这些研究可用于生物大分子的检测和新药的研发，壳聚糖(CS)是目前自然界已被发现的唯一带正电荷的可食用的碱性多糖，分子中含有丰富的氨基和羟基，并具有双螺旋结构，近年来已在食品、医药保健、化妆、环保、农业及化学化工等领域得到广泛应用，

Electrochemical Behaviour of the Interaction Between Chitosan and Alizarin

The interaction between Alizarin red(AR) and Chitosan(CS) was investigated in (0.1 mol/L) HAc-NaAc buffer solution(pH=4.5) on the glassy carbon electrode(GC) by cyclic and square wave voltammetry. The results show that both AR and AR-CS complex have a well-defined quasi-reversible redox wave(V_pc=-0.46 V, V_pa=-0.41 V) with adsorption characteristics. Electron transfer coefficient(α) and reaction rate constant(K_s) of AR and AR-CS were measured by cyclic voltammetry. The maximum binding numbers m between AR and CS was found to be 2 500. The experiment results confirmed that lower concentration of CS can enhance the detection sensitivity, while higher concentration of CS can lower the detection sensitivity. In the presence of 2.0×10^-5 mol/L AR, the peak current of system are proportional to CS concentration in the range of 1.25×10^-8～2.5×10^-7 mol/L, and inversely proportional to CS concentration in the range of 2.5×10^-7～1.25×10^-5 mol/L, respectively. The binding interaction mechanism was also discussed.