Raspberry-Mimic Immunomagnetic Nanoparticles for Specific Capture of Neuronal-Enriched Extracellular Vesicles for Accurate Alzheimer’s Disease Diagnosis

Alzheimer’s disease (AD) is an irreversible neurodegenerative disease, making noninvasive early diagnosis crucial for delaying disease progression and reducing the caregiving burden. Neuronal-enriched extracellular vesicles (NEEVs) have emerged as promising biomarkers for AD liquid biopsy. However, the scarcity of NEEVs and the lack of straightforward and specific enrichment methods limit their wider clinical application. Herein, we developed a novel capture strategy based on raspberry-mimic immunomagnetic nanoparticles (RIMNPs) for specific enrichment of intact NEEVs in one step. By combining analysis of dual NEEVs surface biomarkers NEEVs@p-tau217 and NEEVs@Aβ42 oligomers, a powerful model was constructed for accurate AD diagnosis. The RIMNPs ensure exceptionally specific enrichment of NEEVs while preserving their integrity and bioactivity. Compared with gold standard ultracentrifugation, the RIMNPs exhibited superior separation performance, achieving 5.9-fold enhancement in the purity of NEEVs. Furthermore, RIMNPs demonstrated efficient enrichment with 93.1% capture efficiency and 84.4% recovery. In clinical samples, the dual-biomarker combined with machine learning, yielding 96.4% sensitivity, 100% specificity and precision, and 98.2% accuracy in AD diagnosis, outperforming the discriminative performances of each single biomarker. This work integrates efficient enrichment of NEEVs by RIMNPs and detection of their surface dual-biomarkers, demonstrating superior diagnostic performance and offering a promising avenue for noninvasive, EVs-based liquid biopsy.