The difficult energy situation in the summer of 2021 in Europe has once again made questions like "What should energy be spent on first?" relevant. We are used to modern cities being almost brighter at night than during the day, but this is an excessive, parasitic waste of electricity. Instead, biophysicists at the Massachusetts Institute of Technology propose using luminescent plants to passively illuminate public spaces.
They are talking about a new direction in science called "plant nanobionics," in which various particles are embedded in living tissues to give them new properties. Last year, this led to the creation of a blast-responsive spinach sapper, living soil moisture sensors, and cress that glows in the darkness. The latter has been the subject of special interest, and a modified, improved version was recently introduced.
In the first version, the glow was achieved by adding components of luciferase and luciferin, borrowed from fireflies. In the new version, they were replaced with luminophores, strontium aluminate, which accumulates ultraviolet radiation to then emit energy during phosphorescence. To protect plant tissues, the nanoparticles were packaged in a silica shell and placed in the mesophyll layer inside the leaf.
Light from plants with phosphors is 10 times brighter than that of luciferase, and to activate such a light, it is enough to irradiate it with ultraviolet light for only 10 seconds. True, the system gives maximum brightness for only a few minutes, and then gradually fades for several hours. But the main thing here is something else - scientists were convinced that such additives do not interfere with the natural processes of plant life. Therefore, new experiments, such as combining luminophores and luciferase to produce a combined light source, can be conducted safely.