Table 3.

Comparison of the seven methods

Isolation methods	Advantages	Disadvantages
Differential centrifugation with addition of 30% sucrose buffer solution	High yield Slightly lower contamination	Time-consuming Large amount of sample needed [23, 24]
Precipitation	High separation	Low purification rate Long cycle Susceptible to contamination [25–29]
Flushing separation	Saves time and cost	wash off some exosomes [30]
Ultrafiltration	No chemical reagent contamination Stable structure	Mixed with other particles of similar size [31–34]
Immunomagnetic bead method	High specificity easy operation	Easily affected by pH and salt concentration [11, 35–41]
Microfluidic separation	Small sample requirements, efficient and simple	Lack of standardised clinical samples and large-scale experiments; Small single separation [42, 43]
Mass spectrometry	Good reproducibility, low sample consumption, stable test results	High cost [44, 45]