AbstractThe development of novel nanomaterials brings new opportunity and challenge for high sensing detection of biomolecules. The authors describe the preparation of 3-dimentional hollow graphene balls (3D HGBs) using nickel nanoparticles (Ni-NPs) as the template. The Ni-NPs were synthesized by chemical reduction of nickel chloride and then graphene was coated onto their surface via carburization and carbonization. After etching Ni-NPs, 3D HGBs with few layers and a typical size of 100 nm were obtained. They were sprayed onto indium tin oxide glass to obtain a working electrode for electrochemical determination of levodopa in the presence of uric acid. Due to the unique hollow porous structure of the 3D HGBs, the electrode exhibits a sensitivity of 0.69 μA·μM−1·cm−2 and a 1 μM limit of detection. It is selective, reproducible and stable. It was applied to the determination of levodopa in spiked human plasma samples and it is of potential use in clinical research. Graphical abstractSchematic presentation of the preparation of 3-dimensional hollow graphene balls (HGBs) by using nickel nanoparticles as a template that can be removed by etching. The HGBs were sprayed onto indium tin oxide (ITO) glass to obtain a working electrode that has a sensitivity of 0.69 μA⋅μM−1·cm−2 and a 1 μM limit of detection for the determination of levodopa.

中文翻译：

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在尿酸存在下用于左旋多巴伏安法传感的 3 维空心石墨烯球

摘要 新型纳米材料的发展为生物分子的高传感检测带来了新的机遇和挑战。作者描述了使用镍纳米粒子 (Ni-NP) 作为模板制备 3 维空心石墨烯球 (3D HGB)。Ni-NPs通过氯化镍的化学还原合成，然后通过渗碳和碳化将石墨烯涂覆在其表面。蚀刻 Ni-NPs 后，获得了层数少、典型尺寸为 100 nm 的 3D HGB。将它们喷涂到氧化铟锡玻璃上以获得工作电极，用于在尿酸存在下电化学测定左旋多巴。由于 3D HGBs 独特的空心多孔结构，电极表现出 0.69 μA·μM-1·cm-2 的灵敏度和 1 μM 的检测限。它具有选择性、可重复性和稳定性。它用于测定加标人血浆样品中的左旋多巴，在临床研究中具有潜在用途。图形摘要使用镍纳米颗粒作为模板制备 3 维空心石墨烯球 (HGBs) 的示意图，该模板可以通过蚀刻去除。将 HGB 喷涂到氧化铟锡 (ITO) 玻璃上以获得灵敏度为 0.69 μA·μM-1·cm-2 和 1 μM 检测限的工作电极，用于测定左旋多巴。