How does pre- and post-analytical processing of human biospecimens affect bacterial extracellular vesicle separation and characterization?
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Pre- and post-analytical processing of human biospecimens significantly impact the separation and characterization of bacterial extracellular vesicles (BEVs). Variability in preanalytical approaches can reach up to 94%, emphasizing the importance of common standard operating procedures (SOPs) to control conditions. Different extraction methods yield varying results in terms of concentration, purity, and expression profiles of EVs, with ultracentrifugation offering high yield and low contamination. Size exclusion chromatography (SEC) has been proposed as a high-purity technique for isolating bacterial EVs, showing success in separating bacterial EVs from smaller particles in heterogeneous samples. Optimal pre-analytical handling, including plasma preparation and anticoagulant selection, is crucial for valid measurements of EV concentration and size distribution, with postprandial lipidemia affecting EV measurements and necessitating optimization of separation procedures. The presented step-by-step procedure for separating and characterizing BEVs from human body fluids involves ultrafiltration, SEC, and density-gradient centrifugation, enabling the isolation and characterization of BEVs within 72 hours.
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39 Citations | Not addressed in the paper. |
104 Citations | Pre-analytical processing involves ultrafiltration, size-exclusion chromatography, and density-gradient centrifugation to separate bacterial extracellular vesicles (BEVs) from human body fluids, followed by post-separation biochemical characterization. |
| Pre-analytical processing of human biospecimens can impact bacterial extracellular vesicle (EV) separation. Size exclusion chromatography (SEC) with CL-4B Sepharose beads shows promise for isolating bacterial EVs effectively. | |
| Not addressed in the paper. | |
| Not addressed in the paper. |
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