[ACS Synthetic Biology] A scalable device for automated microbial electroporation in a digital micro
Electrowetting on dielectric (EWD) digital microfluidic laboratory-on-chip platforms demonstrate excellent performance in automating labor-intensive protocols. When coupled with an on-chip electroporation capability, these systems hold promise for streamlining cumbersome processes such as multiplex automated genome engineering (MAGE). We integrated a single Ti:Au electroporation (EP) electrode into an otherwise standard parallel-plate EWD geometry to enable high-efficiency transformation of E. coli with reporter plasmid DNA in a 200 nL droplet. Test devices exhibited robust operation with more than 10 transformation experiments performed per device without cross-contamination or failure. Despite intrinsic electric-field non-uniformity present in the EP/EWD device, peak on-chip transformation efficiency was measured to be 8.6±1.0×108 cfu·μg-1 for average applied electric field strengths of 2.25±0.50 kV·mm-1. Cell survival and transformation fractions at this electroporation pulse strength were found to be 1.5±0.3% and 2.3±0.1%, respectively. Our work expands the EWD toolkit to include on-chip microbial electroporation and opens the possibility of scaling advanced genome engineering methods, like MAGE, into the sub-microliter regime.
Andrew C. Madison, Matthew W. Royal, Frederic Vigneault, Liji Chen, Peter B. Griffin, Mark Horowitz, George M. Church, and Richard B. Fair ACS Synth. Biol., Just Accepted Manuscript DOI: 10.1021/acssynbio.7b00007 Publication Date (Web): May 31, 2017 Copyright © 2017 American Chemical Society