Department of Chemistry, Nanchang University, Nanchang 330031, People's Republic of China.
Biosens Bioelectron. 2009 Dec 15;25(4):852-7. doi: 10.1016/j.bios.2009.08.048. Epub 2009 Sep 3.
A novel experimental methodology based on the unique characteristics of chitosan-branched ferrocene (CS-Fc) and gold nanoparticles (Au NPs) was developed to design a label-free amperometric immunosensor for the sensitive detection of hepatitis B surface antigen (HBsAg) as a model protein. The controllable electrodeposition of CS-Fc solution formed a three-dimensional robust film with good biocompatibility and large surface area for the assembly of Au NPs and further immobilization of hepatitis B surface antibody (HBsAb) on an electrode. The morphologies and electrochemistry of the formed nanocomposite biofilm were investigated by using scanning electron microscopy and electrochemical techniques including cyclic voltammetry and electrochemical impedance spectroscopy, respectively. The HBsAg concentration was measured through the decrease of amperometric responses in the corresponding specific binding of antigen and antibody. The decreased differential pulse voltametric values were proportional to the HBsAg concentration in the range of 0.05-305ngmL(-1) with a detection limit 0.016ng. This would provide an approach for the application of mediator in immunoassays.
一种基于壳聚糖支载二茂铁（CS-Fc）和金纳米粒子（Au NPs）独特特性的新型实验方法被开发出来，用于设计无标记的安培免疫传感器，以灵敏检测乙型肝炎表面抗原（HBsAg）作为模型蛋白。CS-Fc 溶液的可控电沉积形成了具有良好生物相容性和大表面积的三维坚固薄膜，用于 Au NPs 的组装和乙型肝炎表面抗体（HBsAb）在电极上的进一步固定。通过扫描电子显微镜和电化学技术（包括循环伏安法和电化学阻抗谱）分别研究了形成的纳米复合生物膜的形貌和电化学性质。通过测量抗原和抗体特异性结合过程中安培响应的降低来检测 HBsAg 的浓度。差分脉冲伏安法值的降低与 HBsAg 浓度在 0.05-305ngmL(-1)范围内呈正比，检测限为 0.016ng。这将为介体在免疫分析中的应用提供一种方法。
