光导纤维胆固醇生物传感器的研究

将胆固醇酯酶、胆固醇氧化酶和辣根过氧化物酶通过戊二醛交联反应,固定在牛血清蛋白上,制成光纤胆固醇生物传感器的传感膜.此传感器偶合了胆固醇酯水解、胆固醇的氧化和鲁米诺同过氧化氢的化学发光等3种酶催化反应,通过光纤输出的化学发光信号进行检测.测定总胆固醇和自由胆固醇的线性范围均为0.5～20μg/mL,检测下限为0.1μg/mL,响应时间为2min,寿命在2个月以上,适用于血清中总胆固醇和游离胆固醇的测定.

A Fiber Optic Biosensor for the Determination of Cholesterol

A Fiber optic biosensor responding to both of cholesterol esters and free cholesterol is prepared by covalently coupling cholesterol esterase, cholesterol oxidase and horseradish peroxi-dase to bovine serum albumin via glutaraldehyde and making a membrane to end of fiber-optic handle.This sensor is based on cholesterol esterase and catalyzes the hydrolysis of cholesterol esters to free cholesterol, then the cholesterol oxidase in the prescence of oxygen oxidizes the free cholesterol to 4-cholestene-3-one and hydrogen peroxide, which reacts with luminol under the catalysis of horseradish peroxidase to produce chemiluminescence.The linear range for cholesterol is 0.5-20 μg/mL.The detection limit is 0.1 μg/mL.The response time is 2 min.The life time of membrane is longer than 2 months.This biosensor has been applied to determining the total cholesterol and free cholesterol in serum with specificity.