Anionic Liposomes as Optimal Membrane Fusion Carriers Enabling in Situ Multiplexed Detection of Extracellular Vesicle MicroRNAs

Extracellular vesicle (EV) microRNAs (miRNAs) are promising liquid biopsy biomarkers for non-invasive diagnosis, monitoring, and therapeutic evaluation of cancer. However, sensitive EV miRNA detection is hindered by complex pre-analytical processing. Here, the authors present an anionic liposome (AL) assisted membrane fusion strategy enabling one-step multiplexed quantification of EV miRNAs directly from plasma without EV isolation or RNA extraction, termed EValarm (Anionic Liposome Assisted miRNAs Monitoring for Extracellular Vesicles). Liposomes encapsulating probes are prepared using a microfluidic chip, achieving catalytic signal amplification after target recognition of miRNA. Systematic lipid screening identified ALs as optimal carriers, exhibiting minimal background and superior sensitivity compared to cationic and neutral liposomes. The AL-based assay delivered accuracy comparable to quantitative PCR with a streamlined workflow. Applied to 106 clinical samples from lymphoma patients and healthy controls, integration with artificial intelligence achieved high accuracy (AUC > 0.99). In summary, this study demonstrates a platform enabling direct and sensitive plasma EV miRNA detection, offering strong potential for clinical translation in cancer liquid biopsy.