基于碳材料的电化学生物传感器的导电聚合物的开发由于其优异的电,光学,热,物理和化学性质。在这项工作中,基于聚苯胺(PANI)及其胺化衍生物的无标记电化学多巴胺(DA)生物传感器,即,聚(3-氨基苄胺)(PABA),与功能化多壁碳纳米管(f-CNTs)复合,是为了利用导电聚合物作为转换材料而开发的。在优化的条件下,在掺氟氧化锡(FTO)涂覆的玻璃基板上制备了复合材料的静电纺丝纳米纤维。通过衰减全反射-傅里叶变换红外(ATR-FTIR)光谱对PANI/f-CNTs和PABA/f-CNTs电纺纳米纤维进行了表征,X射线光电子能谱(XPS),扫描电子显微镜(SEM)和透射电子显微镜(TEM),这证实了复合材料中f-CNTs的存在。在使用差分脉冲伏安法(DPV)进行DA的无标记电化学检测之前,使用循环伏安法(CV)在磷酸盐缓冲盐溶液中研究了电纺纳米纤维的电活性。传感性能,包括灵敏度,选择性,稳定性,制备的电纺纳米纤维膜的可重复性和再现性也进行了电化学评估。基于PANI/f-CNT和PABA/f-CNT电纺纳米纤维的电化学DA生物传感器在线性范围内表现出6.88µA·cm-2·µM-1和7.27µA·cm-2·µM-1的灵敏度50-500nM(R2=0.98),检测限(LOD)为0.0974µM和0.1554µM,分别。所得DA生物传感器具有良好的稳定性,重复性和再现性,在常见干扰下具有宝贵的选择性,即,葡萄糖,抗坏血酸和尿酸。此外,所研制的电化学DA生物传感器对人工尿液中DA的检测也显示出良好的可靠性。
The development of conducting polymer incorporated with carbon materials-based electrochemical biosensors has been intensively studied due to their excellent electrical, optical, thermal, physical and chemical properties. In this work, a label-free electrochemical dopamine (DA) biosensor based on polyaniline (PANI) and its aminated derivative, i.e., poly(3-aminobenzylamine) (PABA), composited with functionalized multi-walled carbon nanotubes (f-CNTs), was developed to utilize a conducting polymer as a transducing material. The electrospun nanofibers of the composites were fabricated on the surface of fluorine-doped tin oxide (FTO)-coated glass substrate under the optimized condition. The PANI/f-CNTs and PABA/f-CNTs electrospun nanofibers were characterized by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which confirmed the existence of f-CNTs in the composites. The electroactivity of the electrospun nanofibers was investigated in phosphate buffer saline solution using cyclic voltammetry (CV) before being employed for label-free electrochemical detection of DA using differential pulse voltammetry (DPV). The sensing performances including sensitivity, selectivity, stability, repeatability and reproducibility of the fabricated electrospun nanofiber films were also electrochemically evaluated. The electrochemical DA biosensor based on PANI/f-CNTs and PABA/f-CNTs electrospun nanofibers exhibited a sensitivity of 6.88 µA·cm-2·µM-1 and 7.27 µA·cm-2·µM-1 in the linear range of 50-500 nM (R2 = 0.98) with a limit of detection (LOD) of 0.0974 µM and 0.1554 µM, respectively. The obtained DA biosensor showed great stability, repeatability and reproducibility with precious selectivity under the common interferences, i.e., glucose, ascorbic acid and uric acid. Moreover, the developed electrochemical DA biosensor also showed the good reliability under detection of DA in artificial urine.