Digital Microfluidic Approach for Efficient Electroporation with High Productivity: Transgene Expression of Microalgae without Cell Wall Removal

Abstract

A unique digital microfluidic electroporation (EP) system successfully demonstrates higher transgene expression than that of conventional techniques, in addition to reliable productivity and feasible integrated processes. By systematic investigations into the effects of the droplet EP conditions for a wild-type microalgae, 1 order of magnitude higher transgene expression is accomplished without cell wall removal over the conventional bulk EP system. In addition, the newly proposed droplet EP method by a droplet contact charging phenomena shows a great potential for the integration of EP processes and on-chip cell culture providing easy controllability of each process. Finally, the implications of the accomplishments and future directions for development of the proposed technology are discussed.

Microfluidic techniques for enhancing biofuel and biorefinery industry based on microalgae

“…Because common polymeric materials applied in rapid prototyping of microfluidic channels cannot withstand the harsh pressure, temperature, and solvents applied in conventional physical, mechanical, and chemical treatments, electroporation becomes a convenient and favorable process to weaken the cell outer compartments. Starting from 2010, microfluidic electroporation has been applied on the aqueous extraction [79], gene transfection [80, 81], and molecule delivery [82, 83] for microalgae. Owing to the closely arranged electrodes in microfluidic systems, extremely low voltage (1 V–50 V) can be used to generate an electric field larger than thousands of voltage per centimeter.…”

Droplet microfluidics for synthetic biology

“…Another technique directly interfaced pin headers with a microfluidic chamber to improve the controllability of and ease of electroporation. 50 A standard micropipette was used to deliver 1 to 2 μL mixtures of DNA and cells. This system successfully delivered genes to microalgae 50 and Jurkat T cells 56 with efficiencies of ∼6× and ∼10×, respectively, higher than their conventional counterparts.…”

“…50 A standard micropipette was used to deliver 1 to 2 μL mixtures of DNA and cells. This system successfully delivered genes to microalgae 50 and Jurkat T cells 56 with efficiencies of ∼6× and ∼10×, respectively, higher than their conventional counterparts. The authors credited these improvements due to the decreased electric current afforded by the smaller reaction volume.…”

Mechanistic studies of gene delivery into mammalian cells by electrical short-circuiting via an aqueous droplet in dielectric oil

“…The application of electrostatic actuation of water droplets in dielectric oil has also been investigated. Im et al reported electrophoretic actuation of water-in-oil droplets containing living cells [27], and also successfully investigated gene transfection of microalgae [28][29][30] and Jurkat cells [31] using their droplet-based system.…”