Researchers have developed an ingenious way of making mice transparent, so that you can see their little organs, veins, and all their other fleshy circuitry with the naked eye. The secret? Doritos dust.
Well, sort of — so put those grubby fingers away. Specifically, it's the yellow food dye found in those binge-able tortilla chips and many other foods, called tartrazine or "yellow no. 5," that makes the technique possible.
The trick is to mix it into a solution of water and rub it onto the shaved skin of a mouse. And voilà: you've got a yellowish but transparent surface to look through, sort of like those coveted Nintendo 64s in Funtastic Fire Orange.
"You could see through the mouse. I've been working in optics for 30 years, and I thought that result was jaw-dropping," Adam Wax at the National Science Foundation, which partly funded the research, told The Washington Post.
The findings, published as a study in the journal Science, could provide a breakthrough in not just biomedical research but in medicine, since the method is purely topical and doesn't require any incisions.
For example, the orange dye could be used to diagnose deep-seated tumors without surgery, to find veins for drawing blood, or help with cosmetic procedures like tattoo removal, study co-author Gusong Hong, a materials scientist at Stanford University, told WaPo.
Normally our cells refract light, or cause it to bend instead of reflecting straight back, and the extent of this depends on their refractive indices. The higher the refractive index, the more bending.
Since different kinds of cells have different indices — from fats to fluids — the light from deeper tissues bend at different degrees and scatter to the extent that their surface appears opaque.
What the researchers discovered is that when tartrazine dye is applied to body cells, it increases the amount of light they absorb, which means there's less light left to scatter.
"When a material absorbs a lot of light at one color, it will bend light more at other colors," Hong told Nature. "When tartrazine is dissolved in water, it makes water bend light more like fats do," he added. Then as water, fat, and other cells start to bend light at the same index, you have a transparent image.
The researchers tested this by soaking a raw chicken breast in the stuff. Almost like a magic trick, it gradually turned transparent before their eyes. Later, after applying the tartrazine solution to mice, the researchers were able to see some of the creatures' internal organs, blood vessels, and muscle contractions.
A major upside is that the effect goes away when the tartrazine dye is washed off, and since it's a food dye, it shouldn't be toxic. As Nature notes, however, it can only cause transparency to a depth of about three millimeters — at least for now.
"The final goal is to use on a human, and so far, we are limited," Francesco Pavone, a physicist at the University of Florence, told WaPo. "The biggest breakthrough I see here is it could be finally accessible to humans."
More on rodent breakthroughs: Scientists Use Nanoparticles to Remote Control Brains of Mice
Share This Article