Wulff-Type Boronic Acids-Terminated Magnetic Bead as Reusable Platform for Isolating Extracellular Vesicles from Plasma

Extracellular vesicles (EVs) circulating in body fluids offer immense potential for diagnostic applications; however, their clinical utility has been hindered by the lack of efficient isolation methods for complex biological samples (e.g., plasma). To address these limitations, we develop a reusable magnetic bead (MB)-based (ReMag)-EV platform for efficient isolation of high-purity EVs. This platform utilizes Wulff-type boronic acids (WBA), which reversibly bind to carbohydrates on EV membranes under neutral pH, allowing selective EV capture without affecting the integrity due to harsh conditions. Compared to traditional methods, this platform demonstrates significant improvements, yielding 1.3 times more EVs than ultracentrifugation (UC) and 3.1 times more EVs than size-exclusion chromatography (SEC), while achieving higher purity (79.7% lipid particles) that surpasses UC (38.4% lipid particles) and SEC (47.2% lipid particles). Proteomics studies using plasma samples from healthy donors and breast cancer (BC) patients indicate that the ReMag-EV platform isolates 1.88 times more unique proteins than that of UC and captures a much higher proportion (87.56%, vs 78.71% for UC) of database-reported EV proteins (ExoCarta and Vesiclepedia). Comparative analysis of EV protein profiles between healthy donors and BC patients revealed significant differences in protein expression, further highlighting the platform’s ability to isolate high-purity EVs for cancer diagnosis.