基于两种复合纳米材料的电化学生物传感器研究

摘要

构置了基于二氧化硅和四氧化三铁纳米粒子的H2O2电化学生物传感器,研究了Hb的直接电化学和电催化行为,建立了检测H2O2的新方法.结果表明,循环伏安图上出现了Hb的一对峰形良好、准可逆的氧化还原峰,其式量电位为-0.195 V;其电子传递速率常数(Ks)为1.54 s-1；电极响应时间小于2 s;Hb对H2O2具有良好的电催化作用,催化电流与H2O2浓度在1.0×10-7～1.7×10-3 mol/L范围内呈线性关系,检出限为3.3×10-8 moL/L;表观米氏常数KMapp为8.12×10-4 mol/L.与其它过氧化氢电化学传感器相比,此传感器具有灵敏度高、线性范围宽、选择性好等优势.%A hydrogen peroxide biosensor based on Fe3O4 and SiO2 nanomaterials was fabricated and the direct electrochemistry and electrocatalysis of bovine hemoglobin (Hb) at the electrode was investigated.The results showed that the biosensor displayed a pair of well-defined redox peaks with the formal potential (E0') of -0.195 V.The electron transfer rate constant(Ks)was estimated to be 1.54 s-1.The biosensor also exhibited excellent electrocatalytic activity to H2O2.The response time was lower than 2 s; the linearity range for determination of H2O2 is from 1.0×10-7 to 1.7×10-3 mol/L with a detection limit of 3.3×108 mol/L.The apparent Michaelis-Menten constant was calculated to be 8.12×10-4 mol/L.In comparison with other hydrogen peroxide biosensor,this biosensor has the characteristics such as high sensitivity,wide linear range and good selectivity.