Since exosomes carry the genetic information of their parental cells, there is an increasing need for new technologies capable of detecting exosomes with high sensitivity and accuracy. In this study, we propose a dual antibody-modified nanochannel biosensor for rapid, sensitive analysis of exosomes. Two antibodies (anti-CD63 and anti-EpCAM) were simultaneously immobilized on the surface of the porous anodic alumina (PAA) nanochannel to combine with proteins overexpressed on the exosomal membrane. As such, exosomes could be efficiently captured by the dual antibody-modified nanochannel. The captured exosomes effectively covered the nanochannel inlet, leading to remarkable block of ion flow through the channel. Based on this principle, the captured exosomes could be sensitively and accurately detected using a picoammeter. It was found that the use of two antibodies greatly increased the capture efficiency of exosomes compared to that of a single antibody. The results showed that exosomes down to 7.3 × 10³ particles/mL were successfully detected by the nanochannel. Moreover, exosomes were successfully detected from plasma samples using a nanochannel biosensor modified with dual antibody, and the results showed significant differences in the exosomes content in plasma samples of cancer patients and healthy people, so as to initially distinguish cancer patients from healthy people.

由于外泌体携带其亲代细胞的遗传信息，因此对能够以高灵敏度和准确性检测外泌体的新技术的需求日益增长。在这项研究中，我们提出了一种双抗体修饰的纳米通道生物传感器，用于快速，灵敏地分析外泌体。同时将两种抗体（抗CD63和抗EpCAM）固定在多孔阳极氧化铝（PAA）纳米通道的表面上，以与在外体膜上过表达的蛋白质结合。这样，双抗体修饰的纳米通道可以有效地捕获外来体。捕获的外泌体有效地覆盖了纳米通道的入口，从而导致明显的离子流通过通道。基于此原理，可以使用皮安计灵敏而准确地检测捕获的外泌体。发现与单一抗体相比，使用两种抗体极大地提高了外泌体的捕获效率。结果显示外泌体低至7.3×10纳米通道成功检测到^3个颗粒/ mL。此外，使用双抗体修饰的纳米通道生物传感器成功地从血浆样品中检测到了外泌体，结果显示癌症患者和健康人的血浆样品中的外泌体含量存在显着差异，从而初步将癌症患者与健康人区分开。