Table 1.

Summary on the materials of microfluidic devices.

Material	Application	Fabrication technology	Advantage	Disadvantage
Silicon	Point-of-care diagnostics Organ-on-chip devices	Photolithography Wet and dry etching Electron beam lithography	Availability, chemical compatibility, thermostability, ease of fabrication, design flexibility, semiconducting properties, possibility of surface modifications	Opacity, relatively high cost
Glass	Chemical reactions Synthesis of emulsions Polymeric nanoparticles Optical detection		Chemically inert, thermostable, electrically insulating, rigid, biologically compatible, allowing easy surface functionalization, higher resolution, thermal and chemical stability	Expensive and complex fabrication
Polydimethylsiloxane (PDMS)	Organ-on-a-chip Multi-channels Array of a special pattern High-throughput models	Soft photolithography	Cheap, easy to mold, good for prototyping, presenting optical transparency, gas permeability, biocompatibility, low autofluorescence, natural hydrophobicity, high elasticity.	Non-specific molecule adsorption, absorption of less hydrophobic molecules, incompatibility with many solvents, reagents, release of uncrosslinked small PDMS molecules, high cost.
Polymethylmethacrylate (PMMA)	Organ-on-a-chip Micro-physiological systems	Embossing Injection Molding Laser ablation	Better solvent compatibility, no small-molecule absorption, optically transparent, good mechanical properties, allowing surface modification	Poor thermal performance, poor resistance to chemical corrosion, complex processing
Perfluorinated polymers	Cell cultures High-precision assays Super-clean tools Valve and pump fabrications Synthesis devices	Soft lithography	Thermo-processability, chemical inertness, compatibility with organic solvents, excellent antifouling properties	Lack of easy micropatterning and satisfactory elasticity
Cyclo-olefin polymers and copolymers (COPs/COCs)	Synthesis devices in which aggressive solvents are employed	Embossing	Optical transparency, enhanced chemical resistance, low water absorptivity, good electrical insulating properties, long-term stability of surface treatments, low level of impurities	Poor flexibility and lowly biocompatible
Epoxy resins	Organ-on-a-chip	3D printing	Enhanced stability at high temperatures, chemical resistance, transparency, very high resolution with small features.	High cost, poor flexibility, oxygen permeability
Paper	Rapid point-of-care diagnostic testing and medical screening	Wax patterning Alkyl ketene dimer printing Flexographic printing Shaping/cutting	Simplicity, accessibility, significant low costs, high porosity, high physical absorption, ease of manipulation and sterilization, potential for chemical or biological modifications, similarity to the native ECM, bio-affinity, biocompatibility, light weights, the ability to operate without supporting equipment, direct and in situ operation	Poor mechanical strength in a wet state, thickness requirements for achieving transparency