Glycated hemoglobin biosensing integration formed on Au nanoparticle-dotted tubular TiO2 nanoarray.

Excessive glucose present in the blood of diabetic patients binds with the hemoglobin of red blood cells resulting in the formation of glycated hemoglobin (HbA1c). Measurement of HbA1c levels may help in identifying the efficacy of the ongoing treatment and hence provide a better control over the disease. In the present study, we have synthesized a sensitive and stable scaffold, which consists of Au nanoparticles (GNPs)-dotted tubular TiO2, for the construction of an electrochemical HbA1c biosensor. 12-phosphotungstic acid has been used as a reducer after depositing well-dispersed GNPs on TiO2 nanotubes (TiO2 NTs) and an electron mediator by accelerating the electron transfer between the conductor and protein. The fabricated electrode was characterized using scanning electron microscopy (SEM), cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopic analysis (EIS). Biosensor exhibited low detection limit (0.5 μM), fast response time (3 s) and wide linearity (from 0.5 to 2000 μM). The working electrode was used 100 times over 4 months, when stored at 4 °C. The HbA1c biosensor was then effectively used to measure the % of HbA1c in the blood of apparently healthy persons and diabetic patients.