Table 3 Materials used to engineer microfluidic platforms
From: Three-dimensional in vitro culture models in oncology research
Material | Properties/characteristics | Advantages (+) /disadvantages (−) | References |
|---|---|---|---|
Glass | Transparent Stiff No gas permeability Hydrophilic surface | + High optical properties (no intrinsic fluorescence)  + Highly reproducible  + No absorption of molecules − Not permeable to O2 − Prone to breaking − Relatively expensive | [210] |
PDMS | Transparent Soft, flexible Gas permeability Highly hydrophobic surface |  + Rapid prototyping + Low cost  + Permeable to O2  + Low auto-fluorescence − High gas permeability can lead to evaporation − Possible absorption of small hydrophobic molecules and proteins − Poor resistance to solvents and acids/bases − Deformable − Require treatment to increase hydrophobic properties | [211] |
PMMA | Transparent Stiff Low gas permeability Hydrophobic surface |  + Low auto-fluorescence  + Lower cost than PDMS  + lower evaporation rate than PDMS + More resistant to small hydrophobic molecules and proteins absorption than PDMS  + Good solvent and acid/base resistance − Long culture are impossible because of the low O2 permeability − Require treatment to increase hydrophobic properties | |
PC | Transparent Stiff Low gas permeability Hydrophobic surface | + Lower cost than PDMS  + Good solvent and acid/base resistance + More resistant to small hydrophobic molecules and proteins absorption than PDMS − High auto-fluorescence − The low permeability to O2 do not allow long term cultures − Require treatment to increase hydrophobic properties | |
PS | Transparent Stiff Low gas permeability Hydrophobic surface |  + Lower evaporation rate than PDMS  + Good acid/base resistance − Poor resistance to solvents − The low permeability to O2 do not allow long term cultures − High fluorescence − Require treatment to increase hydrophobic properties | |
PU | Transparent Soft to stiff Hydrophobic surface | + Tunable rigidity (duromoter shore hardness from A to D)  + More resistant to small hydrophobic molecules and proteins absorption than PDMS  + Good resistance to abrasion − Require treatment to increase hydrophobic properties | [214] |