Cells Get Electric Jolt, Then A Shot

A low-cost fluidic device containing both micro- and nanochannels enables scientists to deliver controlled amounts of biomolecules into cells quickly and with ease (Nat. Nanotechnol., DOI: 10.1038/nnano.2011.164). Using DNA strands as simple nanochannel templates, L. James Lee and coworkers of Ohio State University fabricated array chips on which pairs of microchannels are connected by a 90-nm-diameter channel. When the researchers placed a cell in each microchannel on one side of the device and loaded drugs or DNA into the microchannels on the other side, and then applied an electrical field across the array, they were able to drive the biomolecules through pores that opened up in the cells’ membranes. “It’s like giving the cells a shot without using needles,” Lee says. The device injected biomolecules with a cell-to-cell variation of 10–12%, he adds, which is less than the variation from delivery techniques using viral vectors and lipid complexes. This level of precision, Lee says, makes the array an analytical tool for studying fundamental cell biology and nanomaterial toxicity.