CSIR-Advanced Materials and Processes Research Institute (AMPRI), Hoshangabad Road, Bhopal 462026, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
ACS Appl Mater Interfaces. 2022 May 11;14(18):20802-20812. doi: 10.1021/acsami.2c03905. Epub 2022 Apr 28.
We develop a highly sensitive electrochemical immunosensor for the detection of a cluster of differentiation-44 (CD44) antigen, a breast cancer biomarker. The hybrid nanocomposite consists of graphene oxide, ionic liquid, and gold nanoparticles (GO-IL-AuNPs) immobilized on a glassy carbon electrode. GO favors the immobilization of antibodies because of the availability of oxygen functionalities. However, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM.BF) and AuNPs facilitate electron transfer and increase the effective surface area, which enhances the performance of the immunosensor. Furthermore, UV-visible, fourier transform infrared and Raman spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, voltammetry, and electrochemical impedance spectroscopy characterization techniques have been employed to investigate the structural and chemical properties of the nanomaterials. The quantitative detection of CD44 antigen has been accomplished via differential pulse voltammetry and EIS detection techniques. It has been quantified that the proposed immunosensor offers excellent detection ability in both phosphate-buffered saline (PBS) and serum samples. Under optimum conditions, the linear detection range of the immunosensor for CD44 antigen is 5.0 fg mL to 50.0 μg mL and the limit of detection is 2.0 and 1.90 fg mL as observed via DPV and EIS, respectively, in PBS. Additionally, the immunosensor has high sensitivity and specificity and can be successfully applied for the detection of CD44 antigen in clinical samples.
我们开发了一种高灵敏度的电化学免疫传感器，用于检测簇分化-44（CD44）抗原，这是一种乳腺癌生物标志物。该杂交纳米复合材料由氧化石墨烯、离子液体和金纳米粒子（GO-IL-AuNPs）组成，固定在玻碳电极上。GO 由于其含氧官能团的存在，有利于抗体的固定。然而，1-丁基-3-甲基咪唑四氟硼酸盐（BMIM.BF）和 AuNPs 促进了电子转移并增加了有效表面积，从而提高了免疫传感器的性能。此外，还采用了紫外可见分光光度法、傅里叶变换红外和拉曼光谱法、X 射线衍射、场发射扫描电子显微镜、透射电子显微镜、伏安法和电化学阻抗谱等表征技术来研究纳米材料的结构和化学性质。通过差分脉冲伏安法和电化学阻抗谱检测技术实现了对 CD44 抗原的定量检测。已经定量地证明，所提出的免疫传感器在磷酸盐缓冲盐水（PBS）和血清样品中都具有出色的检测能力。在最佳条件下，该免疫传感器对 CD44 抗原的线性检测范围为 5.0 fg mL 至 50.0 μg mL，通过 DPV 和 EIS 分别观察到的检测限分别为 2.0 和 1.90 fg mL，在 PBS 中。此外，该免疫传感器具有高灵敏度和特异性，可成功应用于临床样品中 CD44 抗原的检测。
