There is a bold new project from the Google X research lab to monitor your state of health from the inside. The core technology will be an army of magnetic nanoparticles that are circulated through your bloodstream. From there they will bind to any suspicious proteins, sugars or other molecules, and then report to a magnetically-active wristband where further interrogations can take place. Pending favorable FDA review, Google hopes the initial incarnations of the platform could be ready in about five years.

The head of Google X’s life sciences division, Andrew Conrad, described the technology on Tuesday at a conference in Southern California. One key component of the technology, which hasn’t been fully worked out yet, is the delivery vehicle for the nanoparticles. While in theory they could just be injected straight into the bloodstream, Google X has envisioned a pill that upon digestion decomposes to cleanly deliver the particles to the gut.

Once absorbed into the blood, nanoparticles with different coatings will be able to bind to anything from single potassium ions to whole cells in the throes of cancer. The most useful agents might be those that bind to particular proteins that are released by ailing hearts, or lipids that warn of impending stroke. A wrist based sensor could then be periodically activated to magnetically trawl the nanoparticles near for a headcount.

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While magnetic smart particles mere thousandths the size of red blood cells are nothing new, there have been no serious attempts to bring them to a widespread market until now. The Google Fit platform, which was just released yesterday, is one indication of Google’s new commitment to health. Any apps and wearables now available would scarcely be comparable to a magnetic nanoparticle technology, but may give some preview of things to come from Google.

Calico, Google’s anti-aging project, just announced a new $1.5 billion center to focus on life extension. They have recently been partnering with some heavy-hitters in the pharmaceutical arena to address common afflictions like cancer, stroke, and heart disease. The ability to harvest crucial data from internal body sentinels would be useful both to individual wearer and corporate conglomerate alike.

The big “if” in all this is whether or not thousands of metallic flecks canvasing your organs will really be safe. Convincing the FDA of this may be more of a challenge than convincing an eager health-conscious public. Undoubtedly the particles would tend to accumulate in places where they could get up to no good; places like the lymphatic system, the heart valves, or even the brain itself might come to mind.

Getting a better handle on how these particles behave in general circulation — and also how to remove them once their useful tenure is up — is probably the next big concern. From there, even more extravagant potential applications, like MRI-based processing and control of the particles might be imagined for this technology.

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