Department of Physics, Institute of Science, Banaras Hindu University, Varanasi 221005,India.
Nanobioelectronics Laboratory, Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Delhi 110042, India.
Biosens Bioelectron. 2018 May 15;105:173-181. doi: 10.1016/j.bios.2018.01.014. Epub 2018 Jan 12.
Motivation behind the present work is to fabricate a cost effective and scalable biosensing platform for an easy and reliable detection of cancer biomarker Carcinoembryonic antigen (CEA). Here, we report the sensitive and selective detection of CEA using graphene based bio-sensing platform. Large sized (~ 2.5 × 1.0cm), uniform, continuous, single and few layers graphene films have been grown on copper (Cu) substrate employing chemical vapor deposition (CVD) technique using hexane as a liquid precursor. Functional group has been created over Graphene/Cu substrate through π-π stacking of 1- pyrenebutanoic acid succinimidyl ester (PBSE). Further, to make the sensor specific to CEA, antibody of CEA (anti-CEA) has been covalently immobilized onto PBSE/Graphene/Cu electrode. Selective and sensitive detection of CEA is achieved by anti-CEA/PBSE/Graphene/Cu electrode through electrochemical impedance spectroscopy (EIS) measurements. Under optimal condition, the fabricated sensor shows linear response in the physiological range 1.0-25.0ngmL (normal value ~ 5.0ngmL), revealing sensitivity 563.4ΩngmLcm with a correlation coefficient of 0.996 and limit of detection (LOD) 0.23ngmL. In this way, one step electrode fabrication with high specific surface area provides a light weight, low cost, reliable and scalable novel biosensing platform for sensitive and selective detection of CEA. We believe that this bioelectrode equipped with specific recognition elements could be utilized for detection of other biomolecules too.
本工作的目的是制造一种经济高效且可扩展的生物传感平台，用于简便可靠地检测癌症标志物癌胚抗原（CEA）。在这里，我们报告了使用基于石墨烯的生物传感平台对 CEA 进行灵敏和选择性检测。使用化学气相沉积（CVD）技术，通过将己烷用作液体前体，在铜（Cu）衬底上生长出大尺寸（2.5×1.0cm）、均匀、连续、单层和少数层石墨烯薄膜。通过 1-芘丁酸琥珀酰亚胺酯（PBSE）的π-π堆积，在石墨烯/Cu 衬底上创建了官能团。进一步，为了使传感器对 CEA 具有特异性，将 CEA 的抗体（抗-CEA）共价固定在 PBSE/石墨烯/Cu 电极上。通过电化学阻抗谱（EIS）测量，通过抗-CEA/PBSE/石墨烯/Cu 电极实现了对 CEA 的选择性和灵敏检测。在最佳条件下，所制备的传感器在生理范围内 1.0-25.0ngmL（正常值5.0ngmL）显示出线性响应，显示出 563.4ΩngmLcm 的灵敏度，相关系数为 0.996，检测限（LOD）为 0.23ngmL。通过这种方式，一步电极制造具有高比表面积，为灵敏和选择性检测 CEA 提供了一种重量轻、成本低、可靠且可扩展的新型生物传感平台。我们相信，这种配备有特定识别元件的生物电极也可以用于检测其他生物分子。
