Glycated hemoglobin (HbA1c) affinity biosensors with ring-shaped interdigital electrodes on impedance measurement.

Glycated hemoglobin (HbA1c) is one of the most important diagnostic assays for the long-term mark of glycaemic control in diabetes. This study presents an affinity biosensor for HbA1c detection which is label-free based on the impedance measurement, and it features low cost, low sample volume, and requires no additional reagent in experiments. The ring-shaped interdigital electrodes (RSIDEs) are designed to promote the distribution uniformity and immobilization efficiency of HbA1c, and are further employed to characterize the impedance change and identify various concentrations of HbA1c.