TABLE 1.
Performance characteristics of highly specific exosome isolation techniques.
| Isolation technique | Property of separation | Specimen type | Sample volume capacity (µl) | Isolation time (min) | Particle size (nm) | Recovery rate |
|---|---|---|---|---|---|---|
| Dielectrophoresis (Shi et al., 2019) | Dielectric properties shape and size of particles in fluid | Plasma (filtered), serum and saliva (centrifuged and pre-concentrated) | 200 | 20 | 50–150 | NA |
| Dielectrophoresis (Ibsen et al., 2017) | Dielectric properties shape and size of particles in fluid | Plasma | 30–50 | 30 | 50–150 | NA |
| Microfluidic gel electrophoresis and ion-selective separation (Marczak et al., 2018) | Surface properties and particle size | Serum | 25–50 | 10–20 | 130–260 | 60–80% |
| Ion concentration polarization with 3D-printed microtrap (Cheung et al., 2018) | Electrophoretic mobility of EVs, particle size/immunoaffinity and hydrophobic interactions (aldehyde) | EVs in PBS | 30 | 30 | Average size ≈50–75 | Concentrate 100-fold |
| Acoustic trapping (Ku et al., 2018) | Particle size, density and compressibility of particles and fluid | Plasma and urine | 300 | 30 | 154.2 (mean) | 2.4*10^8 particles/ml |
| Immunomagnetic (Zhao et al., 2016) | Immunoaffinity | Plasma | 10—10,000 | 20 | 79.7% < 150 | 72% |
| Immunocapture (Zhang et al., 2019b) | Immunoaffinity | Plasma | 2–125 | 40 for 20 µl sample (0.5 µl/min) | 40–160 | 80–85% |
| Fe3O4@TiO2 particle enrichment (Pang et al., 2020) | Affinity of phosphate head to TiO2 and particle size | Serum (filtered) | 4 | 5 | 30–200 | NA |
| TiO2 particle enrichment (Gao et al., 2019) | Affinity of phosphate head to TiO2 | Serum (filtered) | 1–100 | 5 | 65–235 | 93.4 |
| Tim4- phosphatidylserine affinity (Nakai et al., 2016) | Affinity of Tim4 protein towards phosphatidylserine | Cell culture supernatant (filtered) | 50—4,000 | Overnight | 219 (mean) | 15—20% |
| Nanostructure- functionalized lipid nanoprobe (Wan et al., 2019) | Affinity and particle size | Plasma (filtered) | 1,000—2,000 | 100–200 (10 µl/min) | 50–200 | 28.8% |
Many of the techniques selected display favourable features for adaption within compact microfluidic-based cartridges. Bodily fluid sample often filtered to remove cellular debris and large extracellular vesicles. Fe3O4, Iron oxide, TiO2, Titanium dioxide.