植酸钛纳米材料固定酶制备过氧化氢传感器

利用植酸盐分子中磷酸基团与部分金属离子的强络合能力,通过微波合成法合成植酸钛纳米材料,并运用这种材料结合混合滴涂的方法将辣根过氧化物酶成功修饰到玻碳电极表面.运用紫外-可见光谱和电化学,实验结果证明了这种材料具有良好的生物相容性,有利于防止酶在固定化过程中生物活性的损害.此法制备的生物传感器实现了辣根过氧化物酶(HRP)和玻碳电极之间的直接电子转移,且对过氧化氢呈现出良好的催化还原作用,对H2O2检测的响应电流线性范围是6.67×10-7~4.73×10-5mol·L-1,线性相关系数R=0.9988(n=20),检测限为4.0×10-7mol·L-1(S/N=3),米氏常数(Kapp M)为0.036 mmol·L-1.所制得的生物传感器呈现出良好的重现性和稳定性.

Phytic titanium nanomaterialsfor enzyme sensor of hydrogen peroxide

Due to the strong chelating ability between phosphates groups in phytate and metal ions,we synthesized a new porous nanomaterials-titaniumphytate by the method of microware. Then,we tried to employ the nanoporous film of titaniumphytate as a substrate for making the horseradish peroxidase（HRP） based biosensor by drop-coating method and investigate theelectrochemical behavior of enzyme. The UV-vis absorption spectroscopy and electrochemical results showed that this kind of material has a great biological affinity and it can prevent damage to biological activity of enzyme during immobilization. The as-prepared biosensor realized direct electron transfer between the immobilized HRP and glassy carbon electrode and displayed good bioelectrocatalytic ability toward the reduction of H2O2with a linear response to H2O2over a concentration range from 6. 67 × 10-7to 4. 73 × 10-5 mol·L-1,and a detection limit of 4 × 10-7mol·L-1at a signal-to-noise ratio（ S / N） = 3. The Michaelis – Menten constant Kapp Mwas estimated to be 0. 036 mmol·L-1. The as prepared biosensor exhibited good reproducibility and stability.