Table 2 Internal gelation with water-soluble cross-linkers: mixing cross-linkers with Na-alginate after droplet generation
Reference | Xu et al., 2008 [54] | Liu et al., 2006 [28] | Trivedi et al., 2010 [47] | |
|---|---|---|---|---|
Droplet generation | Concentration of Na-alginate | 2 wt% | 2 wt% | 1 wt% |
Continuous fluid | octyl alcohol oil | soybean oil | silicone oil | |
Use of surfactant | Not mentioned | NO | NO | |
Geometry | Flow-focusing | Flow-focusing | Flow-focusing | |
Microfluidic material | PMMA chip | PDMS chip | Fluoropolymer tubing and junctions | |
Internal gelation by mixing Na-alginate and water-soluble cross-linker | Cross-linkers | CaCl2 (2 wt%) | CaCl2 (2 wt%) | BaCl2 (50 mM) |
Geometry | Cross-flowing | Expansion chamber | Cross-flowing | |
Mixing | Coalescence of flows | Coalescence of droplets | Coalescence of droplets with flow | |