It’s not a plant-induced hallucination – the first bionic plant has been grown in the organic electronics lab at the University of Linköping in Sweden. The researchers, led by Professor Magnus Berggren, have effectively managed to incorporate electronic circuits into a flower’s vascular system, making it possible to circulate an electrical current within the plant without damaging it. They have gone one step further than the architects, biologists and designers who have adopted biomimetics, qtaking inspiration from nature to create innovations. “Our findings pave the way for new technologies and tools based on the amalgamation of organic electronics and plants in general,” predict the authors of the study, published on 20 November 2015 in the periodical Science Advances. So are we living in the age of flower power? Perhaps not: research is in its infancy and promises of such abilities – boosting photosynthesis and storing energy – is still a thorny topic.
Turning flowers into transistors
To turn their rose into a plant cyborg, the authors simply cut off the bottom of a stem before placing the flower in a PEDOT-S:H (or ethylenedioxythiophene) solution, a water-soluble polymer known for its properties of electrical conduction (it is often used in printed circuits). What then? Well, not much. By itself, the plant absorbed part of the mixture, which, through capillary action, entered the plant via its xylem (the equivalent of human arteries through which large quantities of water and nutrients are transported from the soil to the ‘photosynthetic factories’ of the leaves) before structuring itself within the plant tissue. And, in another experiment, it was even possible to change the colour of (living) rose petals by applying a current using this electrical circuit.
Roses in all colours
Removing the plant 24 hours after the start of the experiment, the researchers found that the solution had risen around ten centimetres along the rose’s vessels and solidified, forming an electronic circuit around ten centimetres in length – without affecting the plant’s vital functions. And so the plant had been wired up! By placing two gold electrodes at various points along the circuit, the researchers were able to measure a conductivity of 0.1 siemens per centimetre, almost the same as that of traditional transistors made using PEDOT. And, in another experiment, it was even possible to change the colour of (living) rose petals by applying a current using this electrical circuit.
The infrastructure – although it still needs to be perfected – is in place. So what now? Firstly, the system could be used as a sort of probe designed to precisely measure the concentration of different substances circulating in the roots and stalks. It would then be possible to adjust the supply of water and nutrients, thus promoting plant growth. The researchers’ dream is to use the technology to produce a ‘power plant’. Converting natural ionic signals into electrical signals could lead to us being able to use photosynthesis in plants as a source of energy for humans. Our entire relationship with nature would be turned on its head: “When we have tapped out resources from nature in the past we have always chopped it or burnt it, “Professor Berggren explained to Motherboard. “Maybe this could be a way of tapping energy from plants without having to kill them.”
To go further
Power-generating wind trees
Energy storage: the philosopher’s stone of the 21st century?Glow-in-the-dark trees that could replace street lights
Electronic plants (in Science Advances)
Scientists Made an Electronic Circuit Inside a Rose (in Motherboard)