A novel glucose sensor was reported that consisted of two-dimensional (2D) Au nanosphere arrays and glucose-responsive hydrogel film. This sensor exhibited an intense diffraction signal and an obvious diffraction color on a quartz slide due to the strong diffraction intensity of the Au nanosphere arrays. Thus, glucose was detected via the variation of diffraction wavelength and diffraction color, without a high reflective mirror. In addition, by introducing poly(vinyl alcohol) (PVA) to crosslink the phenylboronic acid (PBA)-modified hydrogel film, the diffraction wavelength of the 2D Au nanosphere arrays/hydrogel composite film shifted in the same direction in high ionic strength condition. In particular, it showed a nearly linear red-shift when the glucose concentration increased from 0 mM to 20 mM. Moreover, this glucose sensor displayed good reproducibility. The nearly linear response and good reproducibility were highly helpful for improving practical application of this glucose sensor.
Keywords: 2D Au nanosphere arrays; PVA-PBA-modified-hydrogel composite film; diffraction intensity; glucose detection; linear response.