title: Direct electrochemical detection of kanamycin based on peroxidase-like activity of gold nanoparticles.
abstract: An enzyme-free, ultrasensitive electrochemical detection of kanamycin residue was achieved based on mimetic peroxidase activity of gold nanoparticles (AuNPs) and target-induced replacement of the aptamer. AuNPs which were synthesized using tyrosine as a reducing and capping agent, exhibited mimetic peroxidase activity. In the presence of kanamycin-specific aptamer, however, the single-stranded DNA (ssDNA) adsorbed on the surface of AuNPs via the interaction between the bases of ssDNA and AuNPs, and therefore blocked the catalytic site of AuNPs, and inhibited their peroxidase activity. While in the presence of target kanamycin, it bound with the adsorbed aptamer on AuNPs with high affinity, exposed the surface of AuNPs and recovered the peroxidase activity. Then AuNPs catalyzed the reaction between H2O2 and reduced thionine to produce oxidized thionine. The latter exhibited a distinct reduction peak on gold electrode in differential pulse voltammetry (DPV), and could be utilized to quantify the concentration of kanamycin. Under the optimized conditions, the proposed electrochemical assay showed an extremely high sensitivity towards kanamycin, with a linear relationship between the peak current and the concentration of kanamycin in the range of 0.1-60 nM, and a detection limit of 0.06 nM. Moreover, the established approach was successfully applied in the detection of kanamycin in honey samples. Therefore, the proposed electrochemical assay has great potential in the fields of food quality control and environmental monitoring.
authors: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors: Chunshuai
authors: C
authors: Wang
authors: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors: Chang
authors: C
authors: Liu
authors: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors: Jibao
authors: J
authors: Luo
authors: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors: Yaping
authors: Y
authors: Tian
authors: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China. Electronic address: zhounandi@jiangnan.edu.cn.
authors: Nandi
authors: N
authors: Zhou
mesh_terms: D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry / Q000378:metabolism*; D007612:Kanamycin / Q000032:analysis* / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D009195:Peroxidase / Q000378:metabolism*; D013499:Surface Properties
chemical_list: D007612:Kanamycin; D006046:Gold; D009195:Peroxidase
keywords: Aptamer; Differential pulse voltammetry; Gold nanoparticles; Kanamycin; Nanozyme