Scientists often deal with an invisible world, relying to some degree on the powers of informed intuition to form hypotheses. However, to probe these hypotheses—to find any modicum of truth in our educated guesses—we must find creative ways make the invisible visible.
Radioactivity continues to be one of the most powerful tools at a biochemist’s disposal. harnessing radiation’s high-energy powers of penetration, scientists have learned to track and detect the invisible [or at least microscopic] molecules in our cells for study.
A radioactive isotope is an atom with an unstable nuclear arrangement or protons // neutrons. Over time, this isotope reconfigures its nuclear components to reach a more stable state in a process known as *nuclear decay*, releasing energy in the form of ionizing radiation—alpha, beta, or gamma rays. These *radioactive* rays strike any atoms // molecules in their highly energetic trajectories. on impact, enough energy may be transferred from the incoming ray to the electrons they hit to free these electrons from the grasp of their parent atoms. When these excited // orphaned electrons drop back down from their high-energy states to find their parent atoms once more, energy may be released in the form of visible light.
A radioisotope’s power thus comes from its innate instability—its inherent propensity to release these knock-your-electrons-off radioactive rays. Radiation’s ability to illuminate a material on contact is known as radioluminescence. This phenomenon is the scientist’s mode of visualizing the super informative—and often dangerous—face behind the ominous tick-ticking of our geiger counters.
For my own research, I investigate a modification in one single base of an rna molecule that is 2.3 nm small. [That’s 4×10-8 inches!!] Therefore, I am quite literally blind to any experimental results without some sort of visual aid. As my metaphorical high-power reading glasses, I use *hot probe* radioactively labeled with phosphate-32. This probe finds + binds its target, which I can visualize using an imaging plate made of a material that absorbs // records a pattern of radioactively-induced electron excitation [like that in robot // alien girl’s face]. This pattern can be read with a scanner that uses a laser to return the excited electrons back down to their original ground state. The resulting visible light signal is recorded by the scanner and converted it into a fully interpretable digital image—translating invisible radioactive rays into a fully visible // tangible result.
Radioactivity’s glowing qualities have also recommended themselves to an artist duo, who recently exploited these luminescent properties in an exhibit at the 4a center for contemporary asian art in sydney, australia. In what the birds knew, artists ken + julia yonetani use uranium glass to create large sculptures [like the ant below] to draw attention to the fukushima nuclear disaster following the 2011 earthquake + tsunami in japan. Uranium glass, which is only mildly radioactive, can be made by mixing uranium with glass as it melts. When ultraviolet light shines on the glass, the energy from the UV rays excites an electron off each uranium atom. As you may now guess, when the electron drops back down, energy is once again released as the visible fluorescent green light emanating from their sculptures. Harnessing uranium’s intrinsic energetic properties, the artists thus conjure an eerie // foreboding atmospheric quality to their work. For more on what the birds knew visit here.