Table 1.

Summary of devices and particles used in in vitro penetration studies

Devices	Nozzle cross-section
Device A	400 × 400 µm2
Device B	1000 × 400 µm2
Particles	Density (kg/m3)	Size (µm)
Polystyrene-based particles	∼1050	5–7 (avg. 6)
Tungsten	∼19250	avg. 1
pDNA-coated gold	∼19300	0.8–1.5 (avg. 1.15)