Fight Aging!

Robert Freitas, the nanotechnologist and longevity science advocate, has an article in the current Life Extension Magazine, also available online:

Nanotechnology is the engineering of molecularly precise structures and, ultimately, molecular machines. The prefix 'nano-' refers to the scale of these constructions. A nanometer is one-billionth of a meter, the width of about five carbon atoms nestled side by side. Nanomedicine is the application of nanotechnology to medicine. The ultimate tool of nanomedicine is the medical nanorobot - a robot the size of a bacterium, composed of molecule-size parts somewhat resembling macroscale gears, bearings, and ratchets. Medical nanorobotics holds the greatest promise for curing disease and extending health span. With diligent effort, the first fruits of medical nanorobotics could begin to appear in clinical treatment as early as the 2020s.

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Right now, medical nanorobots are just theory. To actually build them, we need to create a new technology called molecular manufacturing. Molecular manufacturing is the production of complex atomically precise structures using positionally controlled fabrication and assembly of nanoparts inside a nanofactory.

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But now it’s time to put our theories to the test. After working closely for three years with Philip Moriarty, one of the leading scanning probe microscopists in the UK, our international colleague is now undertaking direct experiments to build and validate several of our proposed mechanosynthesis tooltips in his laboratory. We are also preparing a research program proposal of our own to solicit additional funding from various US public or private sources to support further mechanosynthesis-related experimental and theory work on a greatly accelerated schedule. We expect these efforts will ultimately lead to the design and manufacture of medical nanorobots for life extension, possibly during the 2020s.

But read the whole article: make machines small enough, and they could interface with our cells to repair damage, replace worn structures, or even replace the function of cells entirely. More effective oxygen-carrying blood cell machines, for example, or hyper-efficient immune cell machines. Cells are just complicated small devices, and we humans are becoming very good at making complicated small devices - it's just a matter of time until we can build better machinery than than the evolved biological devices presently powering our bodies.