Fabrication and Characterization of Electrospun Polyacrylonitrile/Polyaniline–Graphene Oxide Nanoscroll Nanofiber Composite for Potential Glucose Sensing Applications

Abstract:

Wearable sweat biosensors require electrode materials with high surface area, conductivity and mechanical compliance, yet chemically polymerized polyaniline forms dense, low-surface-area films with limited flexibility. In this work, flexible free-standing nanofiber mats were fabricated by coaxial electrospinning, using a sulfuric-acid-doped polyacrylonitrile/polyaniline (PAN/PANI) core and a shell containing graphene oxide nanoscrolls (GONS) at 1 and 3 wt%, followed by gold nanoparticle and ferrocene incorporation, glucose oxidase (GOx) immobilization and a Nafion coating. Scanning electron microscopy showed uniform bead-free fibers with an interconnected pore network and an apparent image-derived porosity of approximately 40%. Energy-dispersive X-ray spectroscopy confirmed the uniform distribution of carbon, oxygen, nitrogen and sulfur across the matrix. Fourier-transform infrared spectroscopy retained the nitrile band at 2243 cm−1 and the quinoid and benzenoid bands at 1547 and 1476 cm−1, while amide bands at 1730 and 1641 cm−1 confirmed retention of protein from enzymes. X-ray diffraction gave crystallinities of 76.6% for GONS and 60% for the pure PANI. Four-point probe measurements showed conductivity increasing from 0.0481 S/cm to 1 wt% GONS to 0.0595 S/cm for the 3 wt% mat with additives. These material and structural characterizations establish a promising foundation for future electrochemical validation and sensor development.

Keywords:

Electrospinning; polyacrylonitrile (PAN); graphene oxide nanoscrolls (GONS); polyaniline (PANI); glucose oxidase (GOx) immobilization.