School of Laboratory Medicine, Hubei University of Chinese Medicine, 1 Huangjia Lake West Road, Wuhan, Hubei 430065, P.R. China.
Hunan Institute of Advanced Sensing and Information Technology, Xiangtan University, Xiangtan, Hunan 411105, P. R. China.
Anal Chem. 2020 Mar 3;92(5):4006-4015. doi: 10.1021/acs.analchem.9b05531. Epub 2020 Feb 20.
Cancerous microvesicles (MVs), which are heterogeneous membrane-bound nanovesicles shed from the surfaces of cancer cells into the extracellular environment, have been widely recognized as promising "biofingerprints" for various cancers. High-performance identification of cancerous MVs plays a vital role in the early diagnosis of cancer, yet it is still technically challenging. Herein, we report a gold nanoparticle (AuNP)-decorated, dual-aptamer modified reduced graphene oxide (RGO) field-effect transistor (AAP-GFET) nanosensor for the label-free, specific, and sensitive quantification of HepG2 cell-derived MVs (HepG2-MVs). After GFET chips were fabricated, AuNPs were then decorated on the RGO surface. For specific capture and detection of HepG2-MVs, both sulfhydrylated HepG2 cell specific TLS11a aptamer (Apt) and epithelial cell adhesion molecule aptamer (Apt) were immobilized on the AuNP surface through an Au-S bond. This developed nanosensor delivered a broad linear dynamic range from 6 × 10 to 6 × 10 particles/mL and achieved a high sensitivity of 84 particles/μL for HepG2-MVs detection. Moreover, this AAP-GFET platform was able to distinguish HepG2-MVs from other liver cancer-related serum proteins (such as AFP and CEA) and MVs derived from human normal cells and other cancer cells of lung, pancreas, and prostate, suggesting its excellent method specificity. Compared with those modified with a single type of aptamer alone (Apt or Apt), such an AAP-GFET nanosensor showed greatly enhanced signals, suggesting that the dual-aptamer-based bio-nano interface was uniquely designed and could realize more sensitive quantification of HepG2-MVs. Using this platform to detect HepG2-MVs in clinical blood samples, we found that there were significant differences between healthy controls and hepatocellular carcinoma (HCC) patients, indicating its great potential in early HCC diagnosis.
癌细胞来源的微小囊泡（MVs）是肿瘤细胞表面脱落到细胞外环境中的异质膜结合纳米囊泡，已被广泛认为是各种癌症有前途的“生物指纹”。高性能的癌细胞 MV 鉴定在癌症的早期诊断中起着至关重要的作用，但它仍然具有技术挑战性。在此，我们报告了一种金纳米粒子（AuNP）修饰的、双适体修饰的还原氧化石墨烯（RGO）场效应晶体管（AAP-GFET）纳米传感器，用于无标记、特异性和灵敏地定量检测 HepG2 细胞来源的微小囊泡（HepG2-MVs）。在制造 GFET 芯片之后，然后在 RGO 表面修饰 AuNPs。为了特异性捕获和检测 HepG2-MVs，巯基化的 HepG2 细胞特异性 TLS11a 适体（Apt）和上皮细胞黏附分子适体（Apt）通过 Au-S 键固定在 AuNP 表面。该纳米传感器为 HepG2-MVs 检测提供了从 6×10到 6×10 颗粒/mL 的宽线性动态范围，并实现了 84 颗粒/μL 的高灵敏度。此外，该 AAP-GFET 平台能够区分 HepG2-MVs 与其他肝癌相关血清蛋白（如 AFP 和 CEA）以及源自人正常细胞和其他肺癌、胰腺和前列腺癌细胞的微小囊泡，表明其具有出色的方法特异性。与单独修饰一种适体（Apt 或 Apt）的修饰相比，这种 AAP-GFET 纳米传感器显示出大大增强的信号，表明基于双适体的生物纳米界面是独特设计的，可以实现更灵敏的 HepG2-MVs 定量。使用该平台检测临床血液样本中的 HepG2-MVs，我们发现健康对照组和肝细胞癌（HCC）患者之间存在显著差异，表明其在早期 HCC 诊断中有很大的应用潜力。
