Graphene patterned polyaniline-based biosensor for glucose detection

Hai Binh Nguyen, Van Chuc Nguyen, Van Tu Nguyen, Thi Thanh Tam Ngo, Ngoc Thinh Nguyen, Thi Thu Huyen Dang, Dai Lam Tran, Phuc Quan Do, Xuan Nghia Nguyen, Xuan Phuc Nguyen, Hong Khoi Phan and Ngoc Minh Phan

Abstract

This paper describes a glucose electrochemical biosensor, layer-by-layer fabricated from graphene and polyaniline films. Graphene sheets (0.5×0.5 cm²) with the thickness of 5 nm (15 layers) were synthesized by thermal chemical vapor deposition (CVD) under ambient pressure on copper tapes. Then they were transferred into integrated Fe₃O₄-doped polyaniline (PANi) based microelectrodes. The properties of the nanocomposite films were thoroughly characterized by scanning electron microscopy (SEM), Raman spectroscopy, atomic force microscopy (AFM) and electrochemical methods, such as square wave voltametry (SWV) and chronoamperometry. The above graphene patterned sensor (denoted as Graphene/Fe₃O₄/PANi/GOx) shows much improved glucose sensitivity (as high as 47 μA mM⁻¹ cm⁻²) compared to a non-graphene one (10–30 μA mM⁻¹ cm⁻², as previously reported in the literature). It can be expected that this proof-of-concept biosensor could be extended for other highly sensitive biodetection