Three-Dimensional Graphene Aerogel-Based Microfluidic Chip for IgG Detection

• 1、Mechanical School, Southeast University, Nanjing, 211189

Abstract：In this paper，a three-dimensional (3D) porous graphene-based microfluidic immuno-biochip for the detection of human immunoglobulin G (human-IgG)via electrochemical impedance spectroscopy (EIS) is developed. The fabricated biosensor contains a miniaturized three-electrode system in the micro-channel, wherein the 3D porous graphene-modified ITO functions as the working electrode (WE). 3D porous graphene aerogel (GA) was prepared by in-suit chemical reduction of graphene oxide with L-ascorbic acid (LA)on the electrode surface andfunctionalized with pyrene carboxylic acid (PCA) and subsequently modified with anti-IgG. After injection of samples containing various concentrations of IgG into the chips, EIS was carried out to measure the Rct change of WE concerning to sampler concentration. Under optimized experimental conditions, the reported biochip presented a linear response to IgG concentration ranging from 5×10-9 to 1×10-6 mg/mL and a low detection limit of 1.6 pg/mL. Given its broad linear range, high sensitivity, simplified operation and short detecting time, this assay can be hopefully applied for clinical detection of typical tumor biomarkers both quantitativiely and qualitatively.

Keywords： Electrochemical impedance spectroscopy Microfluidic Immuno-chip Three-Dimensional Granphene