Figure 4: Single-cell transfection in vivo by electroporation.

(a) In vivo single cell transfection of neuron cells in xenopus laevis. Scale bars: 2 mm for left two and 1 mm for right. Reproduced with the permission from Ref. [80]. (b) In vivo transfection of skin cells by a patchable device using a flexible microneedle arrays with hollow tip for electroporation. Electroporation on the leg of mice induces dosage-depend expression of fluorescence markers. Reproduced with the permission from Ref. [82]. (c) A nanochannel based patch for transfection of epidermis cells in vivo with resolution at single cells. The reference electrode is inserted under the dermis of the mouse skin, and the silicon substrate with nanochannels (500 nm in diameter) is adhered onto the top of the skin. d) After single cell electroporation on mouse, the in vivo imaging system (IVIS) shows high levels of ABM expression. e) The cellular level transfection confirmation with confocal imaging of the dermis and epidermis layers. f) Increased angiogenesis of the skin tissue is observed with a one-time treatment of EFF transfection. g) Single cell electroporation based patch on a mouse limb rescues the limb from necrotizing ischemia as indicated by the increased blood flow for EFF treated limb compared with control. Reproduced with the permission from Ref. [56].