혈색소 및 당화혈색소 측정을 위한 자가진단용 전기화학센서 개발

Abstract

본 논문에서는 Point of Care Testing (POCT)의 일환으로 헤모글로빈 (hemoglobin, Hb)과 당화혈색소 (Glycated hemoglobin, HbA1c)를 측정하는 획기적인 센서를 개발하였다. 빈혈이나 당뇨를 측정하기 위한 기존의 헤모글로빈 또는 당화혈색소의 측정방법은 복잡하고 비싸다는 단점이 있었다. 이에 우리는 전위차 법을 사용하여 2전극을 이용한 간단하고 저렴한 센서를 개발하였다. 센서의 제작을 위해 패터닝(patterned)을 거친 single-walled carbon nanotube (SWCNT) 전극 또는 carbon nanotube paste (CNT paste) 전극을 사용하였다. 헤모글로빈의 농도는 Fe(CN)63-와 헤모글로빈이 반응하여 바뀌는 Fe(CN)63-/4-의 비율에 의해 발생하는 전압의 변화를 Open circuit potential (OCP)로 측정하여 결정하였다. 당화혈색소의 측정은 CNT paste 전극을 사용하여 이뤄졌다. CNT paste 전극을bovine serum albumin (BSA)으로 코팅하여 단백질들이 전극 표면에 흡착되는 것을 방지하였고 그 후 BSA에 3-Aminophenylboronic acid monohydrate (APBA)를 수식하였다. APBA는 diol-boronic acid 결합을 통해 당화혈색소와 선택적으로 결합하고 이는 전압의 변화를 가져온다. 본 연구에서는 앞서 만든 바이오센서를 통해 헤모글로빈과 당화혈색소를 측정하여 높은 상관계수 (R2 > 0.993)와 낮은 상대표준편차 (RSD < 2%)를 나타내는 것을 확인하였다. 또한 인간 유래의 IFCC (International Federation of Clinical Chemistry) 표준 샘플을 이용하여 실제 사람의 혈중 농도에서도 적용이 가능한지를 증명하였다.|As a part of Point-of-Care Testing (POCT), we fabricated a novel biosensor which can detect hemoglobin (Hb) and glycated hemoglobin (HbA1c). For diagnosing anemia or diabetes, existing methods have limitations because they are expensive and complicated. Hereupon, two electrode system with a potentiometric method was employed to make our simple and economical biosensor. The working electrode was composed of patterned single-walled carbon nanotube (SWCNT) electrode or carbon nanotube paste (CNT paste). Hemoglobin concentration was determined by potential shift which occurs when the Hb(Fe2+) react with ferricyanide (Fe(CN)63-). As Fe(CN)63- met Hb(Fe2+), the ratio of Fe(CN)63-/4- changed and the shift was measured by using open circuit potential (OCP) method. In case of HbA1c detection, CNT paste was used as the working electrode. CNT paste was coated by bovine serum albumin (BSA) for preventing protein adsorption. Subsequently, 3-aminophenyboronic acid monohydrate (APBA) was attached to BSA to capture glycated hemoglobin. APBA and HbA1c can form the complex by cis-diol interaction, which brings the potential shift. In this study, Hb and HbA1c was determined through the biosensors and obtained high correlation coefficient (R2 > 0.993) and low relative standard deviation (RSD < 2%). In addition, we demonstrated whether the biosensor could apply to real blood sample by using international federation of clinical chemistry (IFCC) sample which was derived from human.; As a part of Point-of-Care Testing (POCT), we fabricated a novel biosensor which can detect hemoglobin (Hb) and glycated hemoglobin (HbA1c). For diagnosing anemia or diabetes, existing methods have limitations because they are expensive and complicated. Hereupon, two electrode system with a potentiometric method was employed to make our simple and economical biosensor. The working electrode was composed of patterned single-walled carbon nanotube (SWCNT) electrode or carbon nanotube paste (CNT paste). Hemoglobin concentration was determined by potential shift which occurs when the Hb(Fe2+) react with ferricyanide (Fe(CN)63-). As Fe(CN)63- met Hb(Fe2+), the ratio of Fe(CN)63-/4- changed and the shift was measured by using open circuit potential (OCP) method. In case of HbA1c detection, CNT paste was used as the working electrode. CNT paste was coated by bovine serum albumin (BSA) for preventing protein adsorption. Subsequently, 3-aminophenyboronic acid monohydrate (APBA) was attached to BSA to capture glycated hemoglobin. APBA and HbA1c can form the complex by cis-diol interaction, which brings the potential shift. In this study, Hb and HbA1c was determined through the biosensors and obtained high correlation coefficient (R2 > 0.993) and low relative standard deviation (RSD < 2%). In addition, we demonstrated whether the biosensor could apply to real blood sample by using international federation of clinical chemistry (IFCC) sample which was derived from human.