He Chenmeng, Tang Yali, Wang Sai, Liu Jiahui, Chen Ying, Dong Yiyang, Su Haijia, Tan Tianwei
Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology.
Agro-product Safety Research Center, Chinese Academy of Inspection and Quarantine.
Anal Sci. 2017;33(10):1155-1160. doi: 10.2116/analsci.33.1155.
A simple and reliable electrochemical biosensor based on an in situ synthetic Au-reduced graphene oxide (Au-RGO) nanocomposite was constructed in this work, which is considered to be a potential sensing platform for sensitive and selective Bt63 rice detection. UV-vis spectroscopy, transmission electron microscopy (TEM), and cyclic voltammograms of the surface characterization indicated that RGO was prepared successfully and Au nanoparticles were well dispersed on its surface with an average size of 20 nm. The square-wave voltammetry (SWV) response of the electrochemical marker methylene blue (MB) was chosen to monitor the probe immobilization and target hybridization event. Under the optimum conditions, the peak values of MB were linear with the logarithm of the target DNA concentrations being from 1.0 × 10 to 1.0 × 10 M; the detection limit was 3.36 × 10 M. Studies also demonstrated that the DNA biosensor had high reproducibility and stability. At last, we used this biosensor to detect several rice samples; it showed good sensitivity and selectivity. Thus the applicability of the method as an effective tool for genetically modified organism (GMO) quantification was confirmed by its accurate and sensitive results in Bt63 rice screening.
本研究构建了一种基于原位合成金-还原氧化石墨烯（Au-RGO）纳米复合材料的简单可靠的电化学生物传感器，该传感器被认为是用于灵敏且选择性检测Bt63水稻的潜在传感平台。紫外可见光谱、透射电子显微镜（TEM）以及表面表征的循环伏安图表明，成功制备了RGO，且金纳米颗粒以平均尺寸20 nm良好地分散在其表面。选择电化学标记物亚甲基蓝（MB）的方波伏安法（SWV）响应来监测探针固定和靶标杂交事件。在最佳条件下，MB的峰值与靶标DNA浓度的对数在1.0×10至1.0×10 M范围内呈线性关系；检测限为3.36×10 M。研究还表明，该DNA生物传感器具有高重现性和稳定性。最后，我们使用该生物传感器检测了几个水稻样品；结果显示出良好的灵敏度和选择性。因此，该方法在Bt63水稻筛选中准确且灵敏的结果证实了其作为转基因生物（GMO）定量有效工具的适用性。
