Dong Xinwei, Qi Xiaoli, Liu Na, Yang Yuesuo, Piao Yunxian
Key Laboratory of Ground Water Resources and Environment of the Ministry of Education, College of Environment and Resources, Jilin University, 2519 Jiefang Road, Changchun 130021, China.
Key Laboratory of Eco-restoration of Regional Contaminated Environment, Shenyang University, Shenyang 110044, China.
Sensors (Basel). 2017 Apr 11;17(4):836. doi: 10.3390/s17040836.
We developed an accurate and sensitive sensor for electrochemical detection of bisphenol A (BPA) with a high-conductivity graphite nanoparticle (GN) film electrode. The GNs consisted of several stacked graphene sheets and showed a homogenous spherical shape, high conductivity, large surface area and good adsorption properties to BPA. The constructed GN film electrode exhibited improved amperometric current responses such as decreased impedance and lowered BPA oxidation potential compared with those of a pristine electrode, and also possessed a large surface area to allow fast electron transfer and BPA accumulation. A pre-accumulation process with BPA adsorption resulted in considerable current signal enhancement during BPA detection. The loading amount of GNs on the film electrode and the time for target BPA enrichment were optimized. The GN film electrode-based sensor showed high reproducibility and high selectivity for BPA over other reagents. Differential pulse voltammetry experiments revealed that the concentrations of BPA were linearly correlated with the current changes, and the lowest limit of detection of the sensor was 35 nM. Furthermore, the sensor showed great accuracy and reliability, as confirmed by high-performance liquid chromatography measurements. The sensor was also successfully used for BPA determination in groundwater samples, demonstrating its potential for real environmental analysis.
我们开发了一种用于电化学检测双酚A（BPA）的准确且灵敏的传感器，该传感器采用了高导电性石墨纳米颗粒（GN）薄膜电极。GN由几层堆叠的石墨烯片组成，呈均匀的球形，具有高导电性、大表面积以及对BPA良好的吸附性能。与原始电极相比，构建的GN薄膜电极表现出改善的安培电流响应，如阻抗降低和BPA氧化电位降低，并且还具有大表面积以实现快速电子转移和BPA积累。BPA吸附的预积累过程导致BPA检测期间电流信号显著增强。优化了薄膜电极上GN的负载量以及目标BPA富集时间。基于GN薄膜电极的传感器对BPA表现出高重现性和相对于其他试剂的高选择性。差分脉冲伏安法实验表明，BPA的浓度与电流变化呈线性相关，该传感器的最低检测限为35 nM。此外，如高效液相色谱测量所证实的，该传感器表现出很高的准确性和可靠性。该传感器还成功用于地下水样品中BPA的测定，证明了其在实际环境分析中的潜力。
