Novel Uric Acid Sensor Based on Enzyme Electrode Modified by ZnO Nanoparticles and Multiwall Carbon Nanotubes
Novel Uric Acid Sensor Based on Enzyme Electrode Modified by ZnO Nanoparticles and Multiwall Carbon Nanotubes
复制标题
DOI：
10.1080/00032710802677159
复制
发表时间：
2009-03
影响因子：
2
通讯作者：
Yiting Wang;Lei Yu;Ziqiang Zhu;Jian Zhang;Jianzhong Zhu
中科院分区：
文献类型：
--
作者：
Yiting Wang;Lei Yu;Ziqiang Zhu;Jian Zhang;Jianzhong Zhu
摘要在这项工作中，我们报告了一个高灵敏度和稳定的尿酸传感器的基础上的多壁碳纳米管（MWNTs）和ZnO纳米粒子的协同作用的发展。首先将MWNT浇铸在热解石墨（PG）晶片上。ZnO纳米粒子，然后装饰到带负电荷的MWNTs通过汽液固（VLS）生长。由于纳米氧化锌与纳米氧化锌的等电点差异较大，因此将尿酸酶固定在纳米氧化锌表面。最后，在含有尿酸酶的ZnO纳米颗粒层上包覆一层阳离子聚二烯丙基二甲基氯化铵（PDDA），形成了PDDA/尿酸酶/ZnO/MWNTs多层结构。这种独特的多层膜结构为尿酸酶的生物活性提供了良好的微环境，使其对尿酸具有快速的电化学响应。在0.05mol/L（M）磷酸盐缓冲溶液（pH6.8）中，于320 mV（vs. SCE）进行尿酸的安培检测。对于传感器，通过使用差分脉冲伏安法（DPV），可以获得5.0 µM至1 mM的宽线性响应范围，线性灵敏度为393 mA cm− 2 M −1，检测限为2.0 µM（3σ），长期稳定性为160天。还将从传感器获得的人尿液测试结果与光谱法获得的数据进行了比较。对5个不同浓度的尿样，其相对偏差均小于3.8%。回收率在96.5 - 104.0%之间。
Abstract In this work, we report the development of a highly sensitive and stable uric acid sensor based on the synergic action of multiwalled carbon nanotubes (MWNTs) and ZnO nanoparticles. MWNTs were first cast on pyrolytic graphite (PG) wafers. ZnO nanoparticles were then decorated onto the negatively charged MWNTs via the Vapor Liquid Solid (VLS) growth. Uricase was immobilized on the ZnO nanoparticles surface because of their large differences in the isoelectric point (IEP). Last, a cationic polydiallyldimethylammonium chloride (PDDA) layer was coated onto the uricase-contained ZnO nanoparticle layer and resulted in the PDDA/uricase/ZnO/MWNTs multilayer structure. The unique multilayer structure provides a favorable microenvironment to keep the bioactivity of uricase, which led to rapid amperometric response toward uric acid. Amperometric detection of uric acid was carried out at 320 mV (vs. SCE) in 0.05 mol/L (M) phosphate buffer solution (pH 6.8). For the sensor, a wide linear response range of 5.0 µM to 1 mM with a linear sensitivity of 393 mA cm−2M−1, a detection limit of 2.0 µM (3σ), and a long-term stability of 160 days can be obtained by using differential pulse voltammetry (DPV). Testing results in human urine obtained from the sensors were also compared with the data obtained by spectrometry. For five samples with different concentrations of urine, the relative deviations between them were smaller than 3.8%. The recovery was between 96.5 and 104.0%.