Why Is Google Making Synthetic Arms?

A recent feature on The Atlantic posed the interesting question: Why is Google making human skin? Cue the odd, but not entirely surprising, answer that the project is part of the technology giant’s efforts in cancer research, ongoing under the Google Life Sciences division at Google X.

At the health research facility where it employs more than 100 doctors and scientists, Google is working on a magnetic nanoparticle technology that could change the way we test for cancer (and potentially other diseases). James Hamblin, senior editor at The Atlantic, interviewed Andrew Conrad, head of Google Life Sciences, who says, “The central thesis of what we’re trying to do at Google Life Sciences is we’re trying to change medicine from being episodic and reactive — like I go to the doctor when my arm hurts — to proactive and preventative.” To that end, Google is developing a wristband that can detect cancer cells in a person’s blood when they first appear. Conrad showed off the synthetic arms on which Google is testing its ability to detect small particles that flow through the body.

Google envisions patients swallowing a pill that contains nanoparticles that are two thousand times smaller than a red blood cell and are “decorated” with markers that attach to cancer cells. The nanoparticles circulate through the body looking for cancer cells, and then are collected at the wrist with a magnet, where they communicate what they saw. Patients could wear the wristband at regular intervals — twice a month, as Hamblin suggests in the video — and cancer cells would “light up.”

And that’s where the synthetic skin comes in. In order to figure out how to detect the light from the nanoparticles, Conrad needed to figure out how light passes through skin. So Google started making arms out of materials with the same properties of skin, with the same autofluorescence and biochemical components of a real arm, and accounting for variations like different skin tones, varying skin thickness, and other characteristics that differ person to person. Researchers are measuring how light passes through different types of skin so that they can build a device that can effectively detect lighted nanoparticles in the blood.

When asked how far Google is from a realistic implementation of the technology, Conrad says that the researchers have a long journey ahead of them — and that he hopes it’s “years, not decades” until the goal is reached. And when Hamblin asks about potential privacy issues — whether people would find it “weird” to have nanoparticles constantly tracking them — Conrad quips that “it’s way weirder to have cancer cells flowing through your body that are constantly trying to kill you.” The nanoparticle project coincides with Google’s Baseline Study — in which it’s studying 175 healthy volunteers to determine what “health” looks like — and among other things, the study hopes to determine how cancer cells a normal, healthy person should have, minimizing false positives.

The news of Google Life Sciences’ nanoparticle project first broke back in October. In an interview with Backchannel’s Steven Levy at the time, Conrad explained of the nanoparticles, “They’re so little that they can pass through parts of your body, they go through the blood, they go through your lymph system, they just walk around. They’re essentially very benign particles…And they’re decorated with proteins and amino acids and DNA to make them bind to certain things.” He goes on to explain what happens when the nanoparticles are designed to detect a specific molecule that’s important to the diagnosis of a disease:

You can use these nanoparticles to detect rare things like a cancer cell or you can use them to measure common molecules. For example, in one case we put a coating on the nanoparticle that finds sodium — it’s a super common molecule but very important in renal disease. When a sodium molecule comes into the nanoparticle, it causes the nanoparticle to fluoresce light at a different color. So by collecting those nanoparticles at your wrist, where you have a device that detects these changes, we can see what color they’re glowing, and that way you can tell the concentration of sodium.

At the time, Conrad referred to the “molded arms” that he showed to The Atlantic, noting that researchers are able to pump fake blood through them, and effectively concentrate and detect nanoparticles. Google has so far been able to build and decorate the particles, prove that they bind to the intended molecules, and collect and detect them again.

Kevin Bullis of MIT’s Technology Review investigated whether the nanotechnology-based plan will actually work. Experts weighed in, proffering perspectives that largely held that the basic idea of the project is nothing new. While the concept is simple, the execution isn’t. Researchers have been developing magnetic nanoparticle diagnostics and treatments for years, but implementing applications of nanotechnology in the body is very difficult, and Google is unlikely to pull of its implementation of the idea anytime soon.

Because Google intends to apply the technology with a nanoparticle pill that the patient must swallow, basic biology is a significant challenge. Mirkin says that getting the nanoparticles into the bloodstream requires “a big leap of faith.” And that’s before they even circulate, find their way to their targets, and then get collected again for measurement. While Google’s idea is that a magnet held near the blood vessels on the wrist would collect the nanoparticles again, it’s still not clear exactly how the wristband would measure the signal from the nanoparticles. Mirkin says that each of these steps is challenging, and Google will be fighting the body’s natural instinct to eliminate foreign objects.

MIT professor Robert Langer also raises the question of whether the system will be safe, and John McDonald, a professor at Georgia Tech, notes that one of the biggest hurdles encountered so far with nanoparticles is their toxicity. Clay Marsh, chief innovation officer at The Ohio State University Wexner Medical Center, told LiveScience that nanoparticles could injure cells or damage DNA, or even build up in organs like the liver or the spleen.

Additionally, differences in diet and blood chemistry between different people make it harder to reliably diagnose diseases in the way that nanoparticles do. But Jack Hoopes, a professor of medicine at the Geisel School of Medicine at Dartmouth College, said that the concept of nanoparticles binding to specific cancer cells or proteins is feasible, and many researchers, including some at Dartmouth, are working on the technology.

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