Figure 2.
Cross-sectional images of particles penetration profiles after ejection into gelatin at 70 psi inlet pressure. Device A (400 × 400 µm2 channel cross-section) was used for ejections in (A-D, G) and Device B (1000 × 400 µm2 channel cross-section) was used for ejection in (E) where both devices had a single nozzle enabled for ejections. The ejection dose was ∼13.6 µg for low-density particles shown in (A), 200 µg for high-density particles shown in B and C, ∼215 µg for mixture of particles shown in (D and E) and a total of 1mg for multiple ejections shown in G. (A) Penetration of low-density polystyrene-based particles with density of ∼1050 kg/m3. (B) Penetration of tungsten particles with density of ∼19250 kg/m3. (C) Penetration of gold particles with density of ∼19300 kg/m3 that were coated with pDNA at 10 µg DNA in 1 mg of gold. (D and E) Penetration of a mixture of low and high density particles. (F) Maximum penetration of particles in a-e (n = 3). The error bars represent one standard deviation from measured values. (G) Penetration of pDNA-coated gold particles after 5 sequential ejections for 1 mg dose delivery.