Exploring Size Exclusion Chromatography Columns 20 and 35 nm Pore Size Effect for Isolation of Extracellular Vesicles

Area of Science:

• Biochemistry
• Biotechnology
• Molecular Biology

Background:

• Extracellular vesicles (EVs) are promising biomarkers for disease detection.
• Current EV isolation methods often co-isolate impurities like soluble proteins.
• Size-exclusion chromatography (SEC) is a common EV isolation technique but struggles with size-based contaminant removal.

Purpose of the Study:

• To compare the efficacy of SEC columns with different pore sizes (20 nm and 35 nm) for EV isolation.
• To evaluate the impact of pore size on non-EV contaminant removal and EV recovery.
• To assess EV purity and yield using particle concentration, co-isolate analysis, and RNA cargo.

Main Methods:

• Utilized size-exclusion chromatography (SEC) with 20 nm and 35 nm pore size columns.
• Isolated extracellular vesicles (EVs) from pancreatic EndoC-ßH1 cell culture media and human plasma.
• Assessed EV purity and yield through particle concentration, co-isolate detection, and RNA cargo analysis.

Main Results:

• Smaller pore size (20 nm) SEC columns demonstrated enhanced EV purity.
• The 20 nm pore size columns resulted in improved EV recovery and yield compared to 35 nm columns.
• Reduced levels of non-EV contaminants were observed with smaller pore size columns.

Conclusions:

• Smaller pore size SEC columns are more effective for isolating pure extracellular vesicles (EVs).
• Optimized EV isolation using smaller pore SEC columns enhances biomarker studies, especially with limited samples.
• This method improves downstream analyses sensitive to contaminants in EV preparations.