College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Department of Chemistry and Material Science, Hengyang Normal University, Hengyang 421008, PR China; State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, PR China.
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China.
Biosens Bioelectron. 2014 Apr 15;54:468-75. doi: 10.1016/j.bios.2013.11.001. Epub 2013 Nov 8.
Well-dispersed Pd nanoparticles were facilely anchored on graphene oxide (Pd/GO) via a one-pot chemical reduction of the Pd(2+) precursor without any surfactants and templates. The morphology and composition of the Pd/GO nanocomposite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and energy dispersive analysis of X-ray (EDX). The stepwise fabrication process of the Pd/GO modified electrode and its electrochemical sensing performance towards paracetamol was evaluated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The experimental results indicate that the as-synthesized Pd nanoparticles are relatively uniform in size (5-10 nm) without large aggregation and uniformly distributed in the carbon matrix with the overall Pd content of 28.77 wt% in Pd/GO. Compared with the GO modified electrode, the Pd/GO modified electrode shows a better electrocatalytic activity to the oxidation of paracetamol with lower oxidation potential and larger peak current, so the Pd/GO nanocomposite can be used as an enhanced sensing platform for the electrochemical determination of paracetamol. The kinetic parameters of the paracetamol electro-oxidation at Pd/GO electrode were studied in detail, and the determination conditions were optimized. Under the optimal conditions, the oxidation peak current is linear to the paracetamol concentration in the ranges of 0.005-0.5 μM and 0.5-80.0 μM with a detection limit of 2.2 nM. Based on the high sensitivity and good selectivity of the Pd/GO modified electrode, the proposed method was successfully applied to the determination of paracetamol in commercial tablets and human urines, and the satisfactory results confirm the applicability of this sensor in practical analysis.
通过无表面活性剂和模板的 Pd(2+)前体的一锅化学还原，将 Pd 纳米粒子均匀地锚定在氧化石墨烯（Pd/GO）上。通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）、傅里叶变换红外光谱（FTIR）和 X 射线能谱（EDX）对 Pd/GO 纳米复合材料的形貌和组成进行了表征。采用电化学阻抗谱（EIS）、循环伏安法（CV）和差分脉冲伏安法（DPV）对 Pd/GO 修饰电极的逐步制备过程及其对扑热息痛的电化学传感性能进行了评价。实验结果表明，所合成的 Pd 纳米粒子尺寸相对均匀（5-10nm），没有大的团聚，均匀分布在碳基质中，Pd/GO 中总 Pd 含量为 28.77wt%。与 GO 修饰电极相比，Pd/GO 修饰电极对扑热息痛的氧化具有更好的电催化活性，具有更低的氧化电位和更大的峰电流，因此 Pd/GO 纳米复合材料可用作电化学测定扑热息痛的增强传感平台。详细研究了 Pd/GO 电极上扑热息痛电氧化的动力学参数，并优化了测定条件。在最佳条件下，氧化峰电流在 0.005-0.5μM 和 0.5-80.0μM 范围内与扑热息痛浓度呈线性关系，检测限为 2.2nM。基于 Pd/GO 修饰电极的高灵敏度和良好选择性，该方法成功应用于商业片剂和人尿中扑热息痛的测定，满意的结果证实了该传感器在实际分析中的适用性。
