DNA-Cu(II) poly(amine) complex membrane as novel catalytic layer for highly sensitive amperometric determination of hydrogen peroxide
DNA-Cu(II) poly(amine) complex membrane as novel catalytic layer for highly sensitive amperometric determination of hydrogen peroxide
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DOI：
10.1016/j.bios.2005.10.007
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发表时间：
2006-05-15
影响因子：
12.6
通讯作者：
Hasebe, Y
中科院分区：
文献类型：
--
作者：
Gu, TT;Hasebe, Y
通过使用 DNA-Cu(II) 复合物作为新型电催化剂来还原过氧化氢 (H2O2)，制备了一种新型过氧化氢生物传感器。由 DNA 和聚烯丙胺 (PAA) 组成的聚离子复合物 (PIC) 膜充当固定电催化元素铜离子的支持基质。湿态DNA-Cu(II)/PAA膜的圆二色性(CD)光谱表明DNA在膜内以B-like形式存在。 DNA-Cu(II)/PAA膜修饰玻碳(GC)电极的电化学测量表明，嵌入DNA/PAA层的铜离子表现出良好的电化学行为，固定化铜离子与GC电极表面之间的电化学速率常数估计为26.4 s(-1)。所得的 DNA-Cu(II)/PAA/GC 电极对 H2O2 还原表现出优异的电催化活性。传感器测定H2O2的灵敏度受DNA-Cu(II)/PAA膜中铜离子、DNA和PAA等各组分含量的影响。还研究了施加电位、pH、温度、离子强度和缓冲液浓度对传感器响应电流的影响，以获得最佳分析性能。即使存在溶解氧，传感器也对 H2O2 表现出高度灵敏和快速（响应时间小于 5 s）的响应。在空气饱和的 50 mM 磷酸盐缓冲液 (pH 5.0) 中，相对于 Ag/AgCl，在 -0.2 V 条件下获得的传感器稳态阴极电流响应线性增加至 135 μM，检测限为 50 nM。通过对聚离子络合物膜最外层的进一步修饰，有效消除了因Cu(II)还原而产生的抗坏血酸和尿酸的干扰。此外，该传感器表现出良好的重现性和稳定性。 (c) 2005 Elsevier B.V. 保留所有权利。
A novel hydrogen peroxide biosensor was fabricated by using a DNA-Cu(II) complex as a novel electrocatalyst for the reduction of hydrogen peroxide (H2O2). A polyion complex (PIC) membrane composed of DNA and poly(allylamine) (PAA) functioned as a support matrix for immobilization of electrocatalytic element-copper ion. The circular dichroism (CD) spectrum of the DNA-Cu(II)/PAA membrane in wet state showed that the DNA exists in B-like form within the membrane. Electrochemical measurements of the DNA-Cu(II)/PAA membrane-modified glassy carbon (GC) electrode revealed that the copper ion embedded in the DNA/PAA layer exhibits good electrochemical behaviors, and the electrochemical rate constant between the immobilized copper ion and the GC electrode surface was estimated to be 26.4 s(-1). The resulting DNA-Cu(II)/PAA/GC electrode showed an excellent electrocatalytic activity for the H2O2 reduction. The sensitivity of the sensor for the determination of H2O2 was affected by the amount of each component, such as copper ion, DNA and PAA in the DNA-Cu(II)/PAA membrane. Effects of applied potential, pH, temperature, ionic strength and buffer concentrations upon the response currents of the sensor were also investigated for an optimum analytical performance. Even in the presence of dissolved oxygen, the sensor exhibited highly sensitive and rapid (response time, less than 5 s) response to H2O2. The steady-state cathodic current responses of the sensor obtained at -0.2 V versus Ag/AgCl in air-saturated 50 mM phosphate buffer (pH 5.0) increased linearly up to 135 mu M with the detection limit of 50 nM. Interference by ascorbic acid and uric acid due to the reduction of Cu(II) was effectively cancelled by further modification of outermost layer of polyion complex film. In addition, the sensor exhibited good reproducibility and stability. (c) 2005 Elsevier B.V. All rights reserved.