Graphene sensitization of glucose-imprinted polymer (G-IP)-
coated optical fiber has been introduced as a new biosensor for evanescent wave
trapping on the polymer optical fiber to detect low-level glucose. The developed
sensor operates based on the evanescent wave modulation principle. Full
characterization via atomic force microscopy (AFM), Fourier transform infrared
(FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy
(SEM), Raman spectroscopy, high-resolution transmission electron microscopy
(HRTEM), and N2 adsorption/desorption of as-prepared G-IP-coated optical
fibers was experimentally tested. Accordingly, related operational parameters
such as roughness and diameter were optimized. Incorporating graphene into
the G-IP not only steadily promotes the electron transport between the fiber
surface and as-proposed G-IP but also significantly enhances the sensitivity by
acting as a carrier for immobilizing G-IP with specific imprinted cavities. The
sensor demonstrates a fast response time (5 s) and high sensitivity, selectivity, and stability, which cause a wide linear range (10−100
nM) and a low limit of detection (LOD = 2.54 nM). Experimental results indicate that the developed sensor facilitates online
monitoring and remote sensing of glucose in biological liquids and food samples.