TABLE1.

Comparison of the current exosome extraction methods.

Method	Principle	Advantages	Disadvantages	Yield	Purity	Time	Equipment/material cost, $	Reference
Ultracentrifugation	Centrifugation and ultracentrifugation steps	Cost-effective	Time consuming	Low	High	2–20h	∼3000/10	Johnstone et al. (1989); Cvjetkovic et al. (2014); Gudbergsson et al. (2016); Helwa et al. (2017)
			Large primary sample size
		Suitable for large volume preparation	Low accuracy
			Contamination with media proteins
			Time consuming
Ultrafiltration	Centrifugation and filtration	Large primary sample size	Low portability	Low	High	∼20h	1000/20	Cheruvanky et al. (2007); Lobb et al. (2015); Konoshenko et al. (2018)
			Sensitive to centrifugation time
Immunoaffinity enrichment	Nano-magnetic bead	Low primary sample volume	Costly	High	High	∼1h	0/650	Tauro et al. (2012); Greening et al. (2015)
		High accuracy
Microfluidics	Microfluidic devices	Low primary sample volume	High-price	High	High	<2h	4217/1400	Chen et al. (2010); Zhang et al. (2016)
		Easily automated and integrated with diagnosis