Simplified depictions of high throughput, high control methods next to actual images of each method. The electroporation polarities shown are for delivering negative cargos. A. Automated probe-based injection. i. automated injection of zebrafish embryos [87] ii-iii. Different magnifications of an atomic force microscope tip with attached carbon nanotube needle (scale bar = 8 μm and 500 nm, respectively) [48] iv. cell held using a vacuum during injection [50] v-vi. real and simulated deformation during injection (needle diameter = 10 μm) [77]
B. Automated probe-based electroporation. i-ii. image processing showing nuclear site in green and cytoplasmic site in red, followed by automated electrode positioning [90] iii. nanofountain probe electroporation (cell size ~ 10–20 μm) [58] iv. An improved version of nanofountain probe using silicon nitride for a soft touch (scale bar = 30 μm) [13]. C. Flow-through microfluidic electroporation. i. vortex microfluidic electroporation (scale bar ~ 720 μm) [97] ii. microfluidic electroporation device (scale bar = 6 mm) [96] iii. sawtooth microfluidic electroporation (scale bar = 40 μm) [95]
D. Flow-through microfluidic mechanoporation, including cell squeezing and hydroporation. i. microfluidic constrictions for cell squeezing (scale bar ~ 250 μm) [92] ii-iii. microfluidic constrictions showing single and double deformation, respectively (scale bar = 10 μm) [103] iv. hydrodynamic shearing in hydroporation [105] v. spiral hydroporation [104]
E. Nanostructures. i. nanoneedles (scale bar = 2 μm) [110] ii. cell adherent to nanostraws with false color added (scale bar = 10 μm) [121] iii. primary T cells on nanowires with false color added (scale bar = 10 μm) [115] iv. internalized nanowires with the cytoplasm dyed green and the cell membrane dyed red (scale bar = 10 μm) [111] v. neurons adherent to nanowires with false color added (scale bar = 10 μm) [114] vi-vii. silicon nanotubes used for biomolecular cargo delivery (scale bars = 1 um and 10 μm, respectively)[118]
G. Patterned electrode electroporation. i. electrode electroporation device with multiple inputs [149] ii. clover electrodes (scale bar = 5 mm) [143] iii. interdigited electrodes [136] iv. 3D interdigited electrodes (scale bar = 800 μm) [141]
H. Porous substrate electroporation. i. anodic alumina membrane (scale bar = 1 μm) [155] ii. polycarbonate membrane microfluidic device (scale bar = 12 mm) [153] iii. porous array with nanostructure trapping mechanism (scale bar = 200 μm) [161] iv. DAPI stain showing cell seating on porous array (scale bar = 100 μm) [164]. Permission is needed.