机构地区: 绵阳师范学院化学与化学工程学院
出 处: 《理化检验(化学分册)》 2010年第7期738-739,742,共3页
摘 要: 用循环伏安法在pH1.7的氯化钾一盐酸的底液中,得到了芦荟苷良好的氧化峰和还原峰,氧化峰电位(Epr)为-0.386V,还原峰电位(Epn)为-0.441V。峰电流(ipa)与芦荟苷浓度在1.195×10^-5~2.152×10^-4mol·L^-1范围内呈线性关系。检出限(3S/N)为4.78×10^-7mol·L^-1。据此提出了循环伏安法测定芦荟中芦荟苷的含量。还研究了芦荟苷在玻碳电极上的电化学行为,结果表明芦荟苷的电极过程具有吸附性和不可逆性。 In a base solution of HCl-KCl (pH 1. 7), sensitive oxidation and reduction peaks of aloin were observed at the potentials of -0. 386 V (Epc) and --0. 441 V (Epa) respectively as studied by cyclic voltammetry. Linear relationship between values of reduction peak current (ipa) and concentration of aloin was obtained in the range of 1.20×10^-6 ,2. 15×10^-4mol·L^-1 , with detection limit (3S/N) of 4. 78×10^-2mol·L^-1. Based on these facts, a cyclic voltammetrie method for determination of aloin in aloe was proposed. In addition, the electrochemical behavior of aloin at GCE was also studied. An shown by the experimental results, the redox reaction of aloin at GCE was an irreversible and adsorptive process.