SENSORS AND ACTUATORS B-CHEMICAL, cilt.306, 2020 (SCI-Expanded)
Glycosylated Hemoglobin, known as HbA1c, is the most commonly used molecule to track and diagnose the Type II diabetes and gives very convincing accurate results. Tracking the HbA1c is also an early diagnostic tool to indicate diabetes occurrence in high risk patience. Glycosylated hemoglobin is the result of glucose binding of the beta-chain of hemoglobin to N-terminal valine and reflects the average glucose value over the past 2-3 months. HbA1c in the blood concentration of more than 141 mg/dL is often enough to diagnose diabetes. Boronic acid derivatives are often used in HbA1c determination due to the carbohydrate relationship based on the cis-diol interaction and determinations based on this association are mostly carried out by enzymatic sensors and HPLC. In addition to these methods, sensor studies have also started to be developed as an alternative. In this study, it is aimed to determine HbA1c by a surface plasmon resonance sensor (SPR) modified with a boronic acid derivative vinyl phenyl boronic acid. This study is shown that the pH value is an important parameter for binding and the signal received is increased as the concentration increases. Even at low concentrations like 10 mu g/mL, signal can be received and it implies that more accurate measurement can be made at clinical concentration values which are higher. In artificial plasma studies, different sensograms are obtained for human serum albumin, immunoglobulin G, and hemoglobin molecules which all could bind to modified chip and the selectivity to the molecules are distinctively differentiated in comparison with HbA1c.