Research challenges for the diamondoid mechanosynthesis path to advanced nanotechnology

On 5 June 2008, Robert Freitas and Ralph Merkle of the Institute for Molecular Manufacturing (IMM) submitted to IEEE Spectrum the following response to the article “Rupturing the Nanotech Rapture” by Richard A.L. Jones (IEEE Spectrum, June 2008 issue). Their brief letter is reproduced below because Spectrum has chosen to publish only one of the responses it received on this topic.

Several items that Richard Jones mentions are well-known research challenges, not showstoppers. All have been previously identified as such along with many other technical challenges not mentioned by Jones that we’ve been aware of for years. Unfortunately, the article also evidences numerous confusions: (1) The adhesivity of proteins to nanoparticle surfaces can (and has) been engineered; (2) nanorobot gears will reside within sealed housings, safe from exposure to potentially jamming environmental bioparticles; (3) microscale diamond particles are well-documented as biocompatible and chemically inert; (4) unlike biological molecular motors, thermal noise is not essential to the operation of diamondoid molecular motors; (5) most nanodiamond crystals don’t graphitize if properly passivated; (6) theory has long supported the idea that contacting incommensurate surfaces should easily slide and superlubricity has been demonstrated experimentally, potentially allowing dramatic reductions in friction inside properly designed rigid nanomachinery; (7) it is hardly surprising that nanorobots, like most manufactured objects, must be fabricated in a controlled environment that differs from the application environment; (8) there are no obvious physical similarities between a microscale nanorobot navigating inside a human body (a viscous environment where adhesive forces control) and a macroscale rubber clock bouncing inside a clothes dryer (a ballistic environment where inertia and gravitational forces control); and (9) there have been zero years, not 15 years, of “intense research” on diamondoid nanomachinery (as opposed to “nanotechnology”). Such intense research, while clearly valuable, awaits adequate funding — as is now just beginning.

Robert A. Freitas Jr.
Ralph C. Merkle
Institute for Molecular Manufacturing (


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