Table 5.

Comparison of properties of traditional diffusion cell systems and skin-on-a-chip microfluidic devices.

Traditional Diffusion Devices	Skin-On-A-Chip Devices
high tissue need	low tissue need
high active ingredient need	low active ingredient need
high formulation need	low formulation need
macroscale size	microscale size
static system	dynamic system
poor reproducibility	good reproducibility
only ex vivo (or in vitro membranes)	ex vivo and in vitro membranes or cell cultures
high sample volumes	low sample volumes
high cost	low cost
controlled parameters	precisely controlled parameters