核-壳结构TiO_2@Pt复合纳米颗粒修饰的葡萄糖生物传感器

Amperometric Glucose Biosensor based on Assembly of Core/Shell Structure nano-TiO_2@Pt Composite

制备了核-壳结构的TiO2@Pt复合纳米颗粒,并修饰于恒电位沉积的普鲁士蓝-壳聚糖（PB-CS）杂化膜表面,以固定葡萄糖氧化酶.由于TiO2@Pt复合纳米颗粒的引入显著增大了传感器的导电性和酶的固载量,同时CS的掺杂,防止了PB的泄露,使得传感器对葡萄糖具有较好的催化作用.该传感器在1.2×10-6～1.1×10-3 mol·L-1范围内,响应电流与葡萄糖浓度呈良好的线性,相关系数（r）为0.998 6,检出限（S/N=3）达到4.0×10-7 mol·L-1,灵敏度为13.31 mA·mol·L-1·cm-2.对0.3 mmol·L-1的葡萄糖标准溶液连续检测5次,其相对标准偏差为3.8％.

Prussian blue and ehitosan（ PB -CS） composite film was prepared by potentiostatic depo- sition. Core/shell structure nano-TiO2 @ Pt composite was prepared and deposited on the surface of PB- CS composite film, which was utilized to immobilize glucose oxidase （GOD）. nano-TiO2 @ Pt composite could obviously improve electrical conductivity of biosensor and amount of immobilized GOx. Furthermore, CS can effectively protect PB from leaking out, which could increase the catalyt- ic activity of this biosensor. This novel glucose biosensor shows a good linear relationship with glucose concentration in the range of 1.2 × 10-6 - 1.1 × 10-3 mol · L-1 with a correlation coefficient（r） of 0. 998 6. The limit of detection is 4. 0 × 10-7 mol · L-1 and the sensitivity is 13.31 mA · mol ·L-1 ·cm -2 .The relative standard deviation for the method was 3.8% at concentration level of 0. 3 mmol · L-1 glucose standard solution for 5 determinations.