1. Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore, India;2. Department of Physics, Indian Institute of Science, Bangalore, India;3. Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India;4. Robert Bosch Centre for Cyber Physical Systems, Indian Institute of Science, Bangalore, India
Abstract:
An enhanced optical detection of D‐glucose and glycated hemoglobin (HbA1c) has been established in this study using etched fiber Bragg gratings (eFBG) coated with aminophenylboronic acid (APBA)‐functionalized reduced graphene oxide (RGO). The read out, namely the shift in Bragg wavelength (ΔλB) is highly sensitive to changes that occur due to the adsorption of glucose (or HbA1c) molecules on the eFBG sensor coated with APBA–RGO complex through a five‐membered cyclic ester bond formation between glucose and APBA molecules. A limit of detection of 1 nM is achieved with a linear range of detection from 1 nM to 10 mM in the case of D‐glucose detection experiments. For HbA1c, a linear range of detection varying from 86 nM to 0.23 mM is achieved. The observation of only 4 pm (picometer) change in ΔλB even for the 10 mM lactose solution confirms the specificity of the APBA–RGO complex coated eFBG sensors to glucose molecules.
