基于蛋白质直接电子转移的全胆固醇传感器  

Total Cholesterol Biosensor Based on Direct Electrochemistry of Proteins

作　　者：万莉[1] 赵常志[1] 徐华筠[1] 王钦[1] 焦奎[1] 

机构地区：[1]青岛科技大学化学与分子工程学院,生态化工教育部重点实验室,青岛266042

出　　处：《高等学校化学学报》2009年第4期670-674,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20635020)资助

摘　　要：以壳聚糖为载体，将血红蛋白、胆固醇氧化酶及胆固醇酯酶固定在玻碳电极表面，在不使用任何电子媒介体的条件下，利用血红蛋白和电极之间的直接电子转移，制备出高选择性的全胆固醇生物传感器，并用于测定血清中总胆固醇含量．利用循环伏安法和恒电位法研究了该传感器的电化学特性．在优化的实验条件下，该传感器对胆固醇响应的线性范围为10～110mg／dL，检出限为5mg／dL（信噪比的3倍），响应时间为60s．对人血清中总胆固醇的测定表明，RSD小于6．2％，回收率为95％-106％．A highly selective cholesterol biosensor based on the direct electron transfer of hemoglobin-encapsulated chitosan-modified glassy carbon electrode was developed for the determination of total cholesterol in human serum samples. The enzyme electrode was prepared by immobilization of hemoglobin, cholesterol oxidase and cholesterol esterase in chitosan matrix. The H2O2 produced from the catalytic oxidation of cholesterol by cholesterol oxidase was reduced electrocatalytically by immobilized hemoglobin and used for the achievement of sensitive amperometric response to cholesterol. The linear response of cholesterol concentrations was from 10.0 to 110 mg/dL with the correlation of 0. 9965, and the detection limit of cholesterol was estimated to be 5.0 mg/dL at a signal/noise ratio of 3. The cholesterol biosensor can efficiently exclude the interference of commonly coexisted ascorbic acid and uric acid. The relative standard deviation was under 6.2% （ n = 7 ） for the determination of real samples. The biosensor is satisfactory to the determination of human serum samples in comparison with the GPO-PAP method.

关 键 词：胆固醇传感器 胆固醇氧化酶 胆固醇酯酶 血红蛋白 壳聚糖 

分 类 号：O657[理学—分析化学]