Khoobi Asma, Ghoreishi Sayed Mehdi, Behpour Mohsen
Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, P.O. Box 87317-51167, Kashan, I.R. Iran.
Analyst. 2014 Aug 21;139(16):4064-72. doi: 10.1039/c4an00422a.
A highly sensitive electrochemical nanosensor was developed using covalent modification of a glassy carbon electrode (GCE) by self-assembly of a novel Schiff base. Scanning electron microscopy (SEM) and electrochemical techniques were used to investigate the immobilization of the self-assembled monolayer (SAM) on the GCE. The electrochemical behavior of hydroxychloroquine (HCQ) in the presence of uric acid (UA) at the surface of the modified electrode was studied using the differential pulse voltammetry (DPV) technique. Response surface methodology (RSM) is used to optimize the effects of various operating variables such as pH, immersion time, scan rate, step potential and modulation amplitude on the voltammetric response of HCQ. RSM formulates a mathematical model which correlates the independent parameters with the peak current of HCQ. The central composite rotatable design (CCRD) has been applied to conduct the experiments. Then, under the optimized conditions, HCQ was determined in the presence of UA. The electrochemical measurements demonstrated that this biosensor responded well to HCQ, confirming that the self-assembly immobilization method was effective. Also, the interference, the storage stability, and the reproducibility of the biosensor were studied and assessed. The developed nanosensor was economical and efficient, making it potentially attractive for application to real sample analysis.
通过新型席夫碱的自组装对玻碳电极（GCE）进行共价修饰，开发了一种高灵敏度的电化学纳米传感器。利用扫描电子显微镜（SEM）和电化学技术研究了自组装单分子层（SAM）在GCE上的固定化。采用差分脉冲伏安法（DPV）技术研究了修饰电极表面在尿酸（UA）存在下羟氯喹（HCQ）的电化学行为。采用响应面法（RSM）优化了pH值、浸泡时间、扫描速率、步长电位和调制幅度等各种操作变量对HCQ伏安响应的影响。RSM建立了一个数学模型，将独立参数与HCQ的峰值电流相关联。采用中心复合旋转设计（CCRD）进行实验。然后，在优化条件下，在UA存在下测定HCQ。电化学测量表明，该生物传感器对HCQ响应良好，证实了自组装固定化方法是有效的。此外，还对生物传感器的干扰、储存稳定性和重现性进行了研究和评估。所开发的纳米传感器经济高效，使其在实际样品分析应用中具有潜在吸引力。
