Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box. 87317-51167, Islamic Republic of Iran.
Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box. 87317-51167, Islamic Republic of Iran.
Mater Sci Eng C Mater Biol Appl. 2019 Jan 1;94:45-55. doi: 10.1016/j.msec.2018.08.068. Epub 2018 Sep 2.
In this research, differential pulse voltammetry (DPV) coupled with experimental design, was used for determination of p-hydroxybenzoic acid (PHB) in cosmetics. Optimization of effecting parameters was carried out based on rotatable central composite design (RCCD) and response surface methodology (RSM) at the surface of a nanostructured electrode for achieving the best sensitivity. Sol-gel process was used for synthesize of nickel titanate (NiTiO) nanoceramics. The structural and morphological characterization of the nanoparticles was studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Then the NiTiO nanopowders were used for surface modification of a carbon paste modified electrode (CPE). Surface characterization of the electrode was accomplished using SEM, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Under the optimized conditions, the voltammograms exhibited two linear dynamic ranges of 0.7-80.0 μM and 80.0-1000.0 μM for PHB with the detection limit of 62.0 nM (S/N = 3). Finally the NiTiO nanoceramics modified carbon paste electrode (NiTiO/CPE) could be employed for the determination of PHB in real samples with satisfactory results.
在这项研究中，采用差分脉冲伏安法（DPV）结合实验设计，用于测定化妆品中的对羟基苯甲酸（PHB）。基于旋转中心复合设计（RCCD）和响应面法（RSM），对影响参数进行了优化，以在纳米结构电极表面实现最佳灵敏度。采用溶胶-凝胶法合成钛酸镍（NiTiO）纳米陶瓷。通过 X 射线衍射（XRD）、傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）研究了纳米粒子的结构和形态特征。然后，将 NiTiO 纳米粉末用于修饰碳糊电极（CPE）的表面。采用扫描电子显微镜（SEM）、电化学阻抗谱（EIS）和循环伏安法（CV）技术对电极进行了表面表征。在优化条件下，对 PHB 的伏安图呈现出两个线性动态范围，分别为 0.7-80.0 μM 和 80.0-1000.0 μM，检测限为 62.0 nM（S/N = 3）。最后，NiTiO 纳米陶瓷修饰碳糊电极（NiTiO/CPE）可用于实际样品中 PHB 的测定，结果令人满意。
