Rapid nickel-based isolation of extracellular vesicles from different biological fluids

Extracellular vesicles (EVs) are membranous structures that cells massively release in extracellular fluids. EVs are a cargo of cellular components such as lipids, proteins, and nucleic acids that can be a formidable source in liquid biopsy studies searching for disease biomarkers. We recently demonstrated that nickel-based isolation (NBI) is a valuable method for fast, efficient, and easy recovery of heterogeneous EVs from biological fluids. NBI exploits nickel cations to capture negatively charged vesicles. Then, a mix of balanced chelating agents elutes EVs while preserving their integrity and stability in solution. Here, we describe steps and quality controls to functionalize a matrix of agarose beads, obtain an efficient elution of EVs, and extract EV nucleic acids. We demonstrate the versatility of NBI in isolating EVs from media of primary mouse astrocytes, from human blood, urine, and saliva processed in parallel, as well as outer membrane vesicles (OMVs) from Gram-negative bacteria.