Industrial Waste Utilization, Nano and Biomaterials, CSIR-Advanced Materials and Processes Research Institute (AMPRI), Hoshangabad Road, Bhopal 462026, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Biosensors (Basel). 2022 Nov 3;12(11):966. doi: 10.3390/bios12110966.
An innovative electrochemical biosensor based on graphene quantum dots (GQDs) is developed for a simple, rapid, and highly sensitive primary diagnosis of the breast cancer biomarker cluster of differentiation-44 (CD44) antigen. Herein, electrochemical exfoliation of waste dry batteries provides facile, eco-friendly, and cost-effective synthesis of GQDs. Transmission electron microscopy (TEM) analysis reveals that GQDs exhibit spherical shapes with an average diameter of 4.75 nm. Further, electrochemical analysis through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) reveals that the electrochemical properties of GQDs are suitable for biosensing applications. Subsequently, GQDs have a large electroactive surface area that has been utilized for the immobilization of CD44 antibodies to fabricate the electrochemical biosensor. The electroanalytical performance of GQDs for CD44 biosensing capabilities is studied by differential pulse voltammetry (DPV). The developed electrochemical biosensor has high sensitivity with the lowest detection limit (LOD) of 2.11 fg/mL in the linear range of 0.1 pg/mL to 100.0 ng/mL in phosphate buffer saline (PBS). Further, the linear response of the electrochemical biosensor for CD44 antigen concentration is in the range of 1.0 pg/mL to 100.0 ng/mL with a LOD of 2.71 fg/mL in spiked serum samples. The outcomes suggest that the synthesized GQDs demonstrate promising attributes to be utilized as a viable nanomaterial in biosensing applications.
基于石墨烯量子点（GQDs）的创新电化学生物传感器被开发出来，用于简单、快速和高度敏感地对乳腺癌生物标志物 CD44 抗原进行初步诊断。在此，通过电化学剥离废干电池，简便、环保且经济高效地合成了 GQDs。透射电子显微镜（TEM）分析表明，GQDs 呈现出球形，平均直径为 4.75nm。此外，通过循环伏安法（CV）和电化学阻抗谱（EIS）进行的电化学分析表明，GQDs 的电化学性质适合用于生物传感应用。随后，GQDs 具有较大的比表面积，已用于 CD44 抗体的固定化，以构建电化学生物传感器。通过差分脉冲伏安法（DPV）研究了 GQDs 对 CD44 生物传感性能的电分析性能。所开发的电化学生物传感器具有较高的灵敏度，在磷酸盐缓冲盐水（PBS）中的线性范围为 0.1pg/mL 至 100.0ng/mL 时，检测限（LOD）低至 2.11fg/mL。此外，电化学生物传感器对 CD44 抗原浓度的线性响应范围为 1.0pg/mL 至 100.0ng/mL，在添加血清样品中的 LOD 为 2.71fg/mL。结果表明，合成的 GQDs 表现出有前途的特性，可作为生物传感应用中的一种可行的纳米材料。
