Disposable amperometric glycated hemoglobin sensor for the finger prick blood test

The analysis of glycated hemoglobin (HbA1C) content in blood samples is crucial for the diagnosis of diabetes, and it still demands to practically use plenty of a blood sample and a complicated procedure. Hence, we report the development of a disposable amperometric HbA1C sensor for the finger prick blood test through a simple treatment of a drop of blood. To fabricate the sensor probe, the conducting polymer, poly(terthiophene benzoic acid) (pTTBA), was electrochemically grown onto the gold nanoparticles (AuNPs) coated-screen printing electrode, followed by the covalent attachment of aminophenyl boronic acid (APBA) to pTTBA as a host to capture HbA1C in the sample. The catalytic reduction response of hydrogen peroxide by HbA1C itself captured on the sensor probe was monitored as an analytical signal. The experimental parameters for the HbA1C analysis were optimized in terms of concentration of H2O2, pH, temperature, applying potential, and interferences. Under the optimized conditions, the linear dynamic range of HbA1C by amperometry was determined to be from 0.1 to 1.5% and the detection limit was to be 0.052 ± 0.02%. The reliability of the proposed HbA1C sensor was evaluated through the comparison of the results among the conventional method, the impedance method, and the proposed amperometry using a drop of a human peripheral blood sample.