Table 1 Techniques for EV isolation

Differential ultracentrifugation (1.5 mL-25 mL, 3 h-9 h)

• Minimal reagents, consumables, expertise needed

• Suitable for large volumes

• Chemical-free, EV-friendly

• Reliable reproducibility

• Costly equipment

• Low throughput

• Elevated protein contamination

• Cross-contamination risk

• Sterility concerns

Density gradient centrifugation (1.5 mL-25 mL, 2 h-40 h)

• High purity (gold standard)

• Enables specific EV subpopulation isolation

• Affordable reagents

• High equipment cost

• Time/labor intensive

• Possibility of viral particle contamination (from sucrose)

• Significant sample loss

Ultrafiltration (10 μL-150 mL, < 2 h)

• Simple, highly versatile

• Rapid, purity-enhancing

• Suitable for large samples

• Limited filter lifespan (clogging risk)

• Non-EV protein contamination

• EV distortion

Size exclusion chromatography (200 μl-20 ml, 1 min/mL)

• Rapid isolation

• Preserves EV integrity

• Prevents aggregation

• High purity, reproducible

• Low yield

• Low sample volume (not more than 2–5% of the column volume)

• Requires EV concentration for downstream applications

Solubility precipitation (50 μL-10 mL, 30–120 min)

• Quick process

• Kit use reduces labor/equipment needs

• Maintains physiological pH

• Costly reagents

• Non-EV protein contamination

• Poor purity (presence of undifferentiated EV subtypes)

Immunoaffinity-based capture (10 μL-10 mL, < 2 h)

• High purity, reproducibility

• High specificity to EV subpopulations

• Short processing time

• High reagent costs

• Require prior knowledge of exosome tags

• Functional loss without antibody detachment

Microfluidic devices (Variable, 1–15 μL/min)

• Low sample volume and minimal consumables

• Rapid isolation with high purity

• Real-time control, automation option

• Requires use-specific design that increases cost

• Low throughput