Table 2.

Comparison of applications of 3D printed microfluidic channels

application	pros	cons	references
molecule & protein detection	various electrode materials integrated into microchannel; various measurement and functionalities; easy operation in all environments	fabrication complexity with increased number of embedded sensors, large fabrication error width in paper channel	[40, 59, 61, 128, 129]
cell deposition & simulation	at the resolution of individual cells, the possible molecular interactions between cells, 3D concentration of gradients, precise control of fluids, reduced reagent/sample consumption, robust and automated procedure	rather large fluidic channels, discrepancy between the printed and designed channel height	[19, 63–67]
bacterial communities	multiple population, no external force required, little physical damage to cells	hard to predict and control the flow behavior in a channel with varying curvatures, small bacterial concentration in the detection	[68–70, 130]
3D tissue constructs	precise control over various cellular microenvironment, easy formation of desired structures, high throughput, reproducible, multi-layer structures	trade-off between cell density of bioink and nozzle size	[51, 74, 78–82, 85–88, 90, 91]
organ-on-a-chip	accurate position of various tissue samples	throughput is limited by large components with intricate geometries	[15, 17, 92, 118, 131]
organ conformal biopsy	rich diagnostic information, continuous monitoring, direct coupling	unknown long-term effects for human	[94]
Milli- & micro-fluidic reactionware	rapid production and design optimization, quick and versatile material synthesis, high temporal stability	low output volume, inability at high pressure and temperature	[62, 95–97]