The ElectroPen, a lab device based on the humble household lighterS. Himmelstein | January 14, 2020
The commercial butane lighter used in many households to start barbeques and stove pilot lights can now add electroporator to its resume. The common appliance inspired the design of a simple, inexpensive electroporator, a device used in laboratory experiments to open cell walls with controlled jolts of electricity.
The high cost of electroporators, which are of value in bacterial detection, genetic engineering and other applications, has kept them out of many molecular biology research and educational facilities. Researchers from Georgia Institute of Technology sought to overcome this economic barrier by designing an affordable counterpart.
The new ElectroPen described in PLOS Biology incorporates a piezoelectric crystal from a household lighter that was demonstrated to deliver repeatable exponentially decaying pulses of about 2,000 V in 5 milliseconds. The crystal is encased in a 3D-printed chamber with wire passthroughs at the bottom and a hand toggle at the top that is depressed in the same manner as a commercial lighter. The device can be fabricated in 15 minutes at a cost as low as 23 cents.
To test its capabilities, the researchers used the device on samples of Escherichia coli, adding a chemical that makes the bacterial cells fluoresce, illuminating the cell parts and making them easier to identify. Similar techniques could be used in a lab or in remote field operations to detect the presence of microbes of interest.
The researchers have made the plans for building the ElectroPen open source, and will next test a broader range of lighters, looking for consistent voltages across a wider range, with the goal of creating ElectroPens of varying voltages.