Graphene oxide hydrogel improved sensitivity in one-dimensional photonic crystals for detection of beta-glucan

Abstract

Hydrogels are environment sensitive and they were introduced to 1DPhCs to improve the sensitivity in our previous research. In this paper, a new method was developed for quantitative determination of beta-glucan in oats by introducing graphene oxide (GO) hydrogels in one-dimensional photonic crystals (1DPhCs) with a polyaniline (PANI) defect layer. GO hydrogels were synthesized via a one-step hydrothermal method, characterized with scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), and then they were employed as a component to fabricate 1DPhCs using a spin-coating method. Synthesized 1DPhCs combined with Congo red dye were in use for the quantification of beta-glucan. Reflection spectra demonstrated that a linear relationship existed between the photonic band gap and the beta-glucan concentration within 1-10 mg mL À1 . The detection limit for beta-glucan is 0.18 mg mL À1 with a sensitivity of 7.53 nm mL mg À1 . † Electronic supplementary information (ESI) available. See

Design and Optimization of One-Dimensional TiO2/GO Photonic Crystal Structures for Enhanced Thermophotovoltaics

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