Extracellular vesicles (EVs) are very promising biomarkers for the diagnosis of various diseases, including cardiovascular, infectious and neurodegenerative disorders. Of particular relevance is their importance in cancer liquid biopsy, where they play a key role in the early detection and monitoring of the tumour. A number of technologies have recently been developed to improve the performance of current EV detection methods, but a technique that can provide high resolution, high accuracy and a multiplexing capability for the detection of several biomarkers in parallel remains a challenge in this field. Here, we demonstrate the detection of large unilamellar vesicles, which are excellent models of EVs, down to a concentration <10³ EV ml⁻¹ (<10 pM) using a dielectric resonant metasurface. This result represents an improvement in performance and functionality compared to competing plasmonic and electrochemical modalities and is due to the strong resonance amplitude and high Q-factor of our metasurface. We also verify the selectivity of the approach by detecting vesicles that have been surface-functionalised with a CD9 protein. The ease of integration of our method into a point-of-care instrument offers a path towards personalised cancer medicine.

细胞外囊泡 (EV) 是非常有前景的生物标志物，可用于诊断各种疾病，包括心血管、感染和神经退行性疾病。特别相关的是它们在癌症液体活检中的重要性，它们在肿瘤的早期检测和监测中起着关键作用。最近开发了许多技术来提高当前 EV 检测方法的性能，但能够提供高分辨率、高精度和多路复用能力以并行检测多种生物标志物的技术仍然是该领域的一个挑战。在这里，我们展示了大单层囊泡的检测，这是 EV 的优秀模型，浓度低至 <10 ³ EV ml ^-1(<10 pM) 使用介电共振超表面。与竞争的等离子体和电化学模式相比，该结果代表了性能和功能的改进，这是由于我们超表面的强共振幅度和高Q因子。我们还通过检测已用 CD9 蛋白进行表面功能化的囊泡来验证该方法的选择性。我们的方法易于集成到即时护理仪器中，为个性化癌症医学提供了一条途径。