Nature reports on the creation of a rose implanted with electronic circuits:
Researchers at Linköping University have created bionic roses by incorporating plant-compatible electronic materials into them. One of their modified roses has simple digital circuits running through its stem: another’s leaf changes colour when a voltage is applied.
The scientists want to make tools for biologists to record or regulate plant physiology — the plant equivalent of medical implants such as pacemakers. Electronic components might also be a way to engineer plants instead of manipulating their DNA, adds Magnus Berggren, a materials scientist at Linköping University who led the research, published in Science Advances.
Berggren started by submerging the cut end of a rose stem into a solution of PEDOT, a conducting polymer that is commonly used in printable electronics and is soluble in water. Capillary action pulls the polymer up into the rose’s vascular tissue or xylem. There, the polymer came out of solution and self-assembled into wires, some as long as 10 centimetres. By attaching gold probes coated with PEDOT to the wires, the researchers made individual transistors and demonstrated a simple digital circuit using the switches. The transistors’ electrical performance is on a par with that of conventional printed PEDOT circuits, says Berggren.
Next, the researchers put rose leaves in a syringe full of a solution of PEDOT mixed with cellulose nanofibres. By applying a vacuum, they expelled air from the tissue, and then drew the PEDOT solution into the empty spaces left behind. When a voltage is applied, the bionic leaves subtly change colour between bluish greenish hues.
[University of Pittsburgh biomedical engineer Christopher] Bettinger speculates that it might be possible to manipulate a plant — triggering a growth spurt, for example — via its embedded electronic circuits.