Synthesis of graphene/ZnO nanoflowers and electrochemical determination of levodopa in the presence of uric acid
ZnO nanoflowers (ZnONFs) were synthesized by a simple hydrothermal method. Then, ZnONFs suspension was sprayed onto the indium tin oxide coated glass. Finally, graphene was deposited on the surface of ZnONFs (graphene/ZnONFs) by chemical vapor deposition, which is used to electrochemically determine levodopa in the presence of uric acid. The results show that the length and diameter of ZnONFs are ∼ 2.5 µm and 50 nm, respectively. Graphene with multi-layers and some defects are deposited on the surface of ZnONFs. The sensitivity and measured limit of detection of the graphene/ZnONFs for levodopa are 0.32 µA µM−1 and 1 µM in the range of 1–60 µM, respectively. The graphene/ZnONFs also show good selectivity, repeatability and stability for the determination of levodopa. The proposed electrode is also successfully used to determine levodopa in human urine samples and it is potential for use in clinical research.
This work is supported by the Natural Science Foundation of Heilongjiang Province (LC2015020), Technology Foundation for Selected Overseas Chinese Scholar, Ministry of Personnel of China (2015192), the innovative talent fund of Harbin city (2016RAQXJ185) and Science Funds for the Young Innovative Talents of HUST (201604).
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