It seems that stories about emerging -- if not revolutionary -- technologies are becoming more mainstream every day. And you don't have to be a genius to see that these remarkable developments move us steadily closer to the time when all the tools will be there to enable general-purpose molecular manufacturing.
BusinessWeek Online reports on a molecular robot that can walk and pick up and deliver loads of cargo.
Called a motor protein, it has two little feet on one end and a tail that can grab things on the other. Once a special chemical is added to the solution in which it resides, the protein begins moving along strands of fiber that are one-fifth the width of a human hair, says Bruce Bunker, a Sandia researcher who's in charge of the project.
And that's not all...
Nadrian Seeman, professor of chemistry at New York University, dreams of nanorobots so tiny they could be squashed by the foot of a bug. He recently made a molecular device that can execute a half-turn revolution when placed in solution with certain DNA strands. Within a decade, Seeman imagines, this nano-robotic arm could become part of a molecular assembly line -- in a chemical factory so small it might sit on your tabletop.
"[T]he field is moving very fast," says NYU's Seeman. Only a year ago, he says, he showed his students a top-10 list of major challenges nanotechnology faced. Today, three are already resolved. At this pace, he adds, self-assembly and molecular manufacturing will come into commercial use sooner rather than later.
In a similar vein, our friend Rocky Rawstern, editor of Nanotechnology Now, reports:
A rewritable memory and nanotweezers, both made from DNA, show how such 'gene machines' can be given better memories and more self-control.
Jong-Shik Shin and Niles Pierce from the California Institute of Technology in Pasadena have made a rewritable DNA memory. And Wendy Dittmer and Friedrich Simmel of the University of Munich in Germany have used the biological apparatus for reading out genetic information to control the operation of a pair of 'DNA tweezers'.
This isn't likely to be a very good way of storing and reading data for information technology -- it is slow, and addressing every element via its base sequence rather than simply via its grid reference is cumbersome if there are many elements -- but that's not really the goal. Shin and Pierce say that a DNA array with these reversibly addressable sites could be useful as a template for assembling other molecules or nanoscale building blocks into arbitrary patterns. What's more, a judicious sequence of 'write' operations on the array could be used to transport attached cargo step by step along a particular path. So the DNA memory could serve as a track or scaffold for nanoscale assembly.
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