School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, PR China; Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215163, PR China.
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215163, PR China.
Biosens Bioelectron. 2022 Nov 15;216:114647. doi: 10.1016/j.bios.2022.114647. Epub 2022 Aug 22.
Exosome is considered an important biomarker of liquid biopsy in early cancer screening, which can reflect the physiological and pathological status of cancer cells. Herein, we construct a novel electrochemical biosensor based on hierarchical Au nanoarray-modified 2D TiCT MXene membranes for sensitive detection of exosomes. TiCT MXene nanosheets were fabricated as the building blocks for preparing 2D membranes as the sensing platform via vacuum filtration. To enhance the conductivity of the MXene membrane, for the first time, hierarchical Au nanoarrays were further deposited in situ on the MXene membrane surface. The combination of MXene membrane with a large specific area and hierarchical Au nanoarrays with excellent conductivity make higher electrocatalytic and more active sites in aptamer immobilization. In this strategy, the composite membrane modified by EpCAM recognized aptamer can specifically capture target exosomes, meanwhile, these target exosomes anchor aptamer for CD63 to further enhance the sensing sensitivity and accuracy of the biosensor. As a result, the biosensor achieved high sensitivity and reliable performance for exosome sensing, with a low detection limit (58 particles/μL) in the linear range of 1 × 10 to 1 × 10 particles/μL. In addition, this biosensor showed satisfactory electrochemical stability and anti-interference ability for the detection of exosomes in real serum samples.
外泌体被认为是液体活检中早期癌症筛查的一个重要生物标志物，它可以反映癌细胞的生理和病理状态。在此，我们构建了一种基于分级 Au 纳米阵列修饰的二维 TiCT MXene 膜的新型电化学生物传感器，用于敏感检测外泌体。TiCT MXene 纳米片被构建为用于通过真空过滤制备 2D 膜作为传感平台的构建块。为了提高 MXene 膜的导电性，我们首次在 MXene 膜表面原位进一步沉积了分级 Au 纳米阵列。MXene 膜与大比表面积的结合以及具有优异导电性的分级 Au 纳米阵列使更多的电催化和更活跃的固定化适体位点。在该策略中，经 EpCAM 修饰的复合膜可以特异性地识别靶向外泌体，同时，这些靶向外泌体锚定适体用于 CD63，进一步提高了生物传感器的传感灵敏度和准确性。结果，该生物传感器在 1×10 至 1×10 个颗粒/μL 的线性范围内实现了对外泌体检测的高灵敏度和可靠性能，检测限低至 58 个颗粒/μL。此外，该生物传感器在检测真实血清样本中的外泌体时表现出令人满意的电化学稳定性和抗干扰能力。
