标题：Highly selective and sensitive electrochemical sensor for l-cysteine detection based on graphene oxide/multiwalled carbon nanotube/manganese dioxide/gold nanoparticles composite
作者：Wang, Xiaojiao ;Luo, Chuannan ;Li, Leilei ;Duan, Huimin
作者机构：[Wang, Xiaojiao ;Luo, Chuannan ;Li, Leilei ;Duan, Huimin ] Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong (University of 更多
来源：Journal of Electroanalytical Chemistry
摘要：A highly selective and sensitive electrochemical sensor for detection of l-cysteine based on a graphene oxide/carboxylated multiwalled carbon nanotube/manganese dioxide/gold nanoparticles composite (GO/CCNTs/AuNPs@MnO2) was developed. The property of the glassy carbon electrode which was modified by GO/CCNTs/AuNPs@MnO2contributed to increasing the sensing surface area and the electronic transmission rate. Besides, the addition of MnO2could effectively improve the selectivity and specificity of l-cysteine determination. The morphology and composition of GO/CCNTs/AuNPs@MnO2were characterized by scanning electron microscope, energy dispersive spectrometer, fourier transform infrared spectroscopy and X-ray diffractometer and the results evidenced that GO/CCNTs/AuNPs@MnO2flower-like structure was efficiently synthesized. The determination results of l-cysteine indicated that the surface area, electronic transmission rate and sensitivity of GO/CCNTs/AuNPs@MnO2sensor were highly increased. Under the optimal conditions, the electrochemical sensor exhibited excellent analytical performance with good selectivity, reproducibility and stability. The linear range of l-cysteine was from 1.0 × 10- 8to 7.0 × 10- 6mol L- 1and the detection limit was 3.4 × 10- 9mol L- 1(3δ). The proposed electrochemical sensor was successfully applied to the determination of trace l-cysteine in spiked water samples.
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