Efficient streptavidin-functionalized nitrogen-doped graphene for the development of highly sensitive electrochemical immunosensor

Zhanjun Yang*, Qingchun Lan, Juan Li, Jiajia Wu, Yan Tang, Xiaoya Hu*

School of Chemistry and Chemical Engineering, Yangzhou University Yangzhou 225002

Abstract:In this work, an efficient and universal streptavidin-functionalized nitrogen-doped graphene (NG) was for the first time proposed and used to develop a highly sensitive electrochemical immunosensor for the detection of tumor markers.Transmission electron microscopy, electrochemical impedance spectrum, static water contact measurement, and cyclic voltammetry were used to characterize thestreptavidin-functionalized NGplatform and immunosensor. The biofunctionalized NG showedexcellent hydrophilicity, larger specific surface area, and highelectrochemical activity. These properties of the platformenhanced the loading capacity of proteins, and retained the bioactivity of the immobilized proteins, and thus remarkably improved the sensitivity of the immunosensor. Using carcinoembryonic antigen (CEA) as model analyte,the proposed immunosensor demonstrated a wide linear range of 0.02-12 ngmL-1 with a low detection limit of 0.01 ng mL-1.The CEA immunosensor could be applied to detect human serum samples with satisfactory results. Thestreptavidin-functionalized NGmaterial provided an universal and promising platform for the electrochemical immunosensing applications.

Biosens. Bioelectron., 2017, 89, 312-318, IF: 7.476

文章链接:http://www.sciencedirect.com/science/article/pii/S0956566316308892

文章附件：