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DNA Assembled Nano-Transistors
Bob Vila's Hammer writes "In an article at New Scientist, researchers at the Technion-Israel Institute of Technology have harnessed DNA to mold a nano-transister constructed of graphite nanotubes coated in silver and gold. The carbon nanotube assembly when completed is a fully working transistor when voltage is applied. The process is ingenious, using proteins from E. Coli bacterium to bind carbon nanotubes to certain sites on strands of DNA. Then graphite nanotubes coated with antibodies connect to the proteins. Finally, silver ions are added to the solution which chemically bond with the DNA site where the protein is attached. Further refinement of the technique is required before full scale production would be efficient, but this could allow the creation of elaborate self-assembling DNA sculptures and circuitry."
This process was first performed at MIT by Angela Belcher. She was using engineered viruses that coated themselves with semiconductor materiel to produce nanoscale FET trasnsitors a billionth of a meter in size. You can read more in the November issue of IEEE Spectrum.
So what's next DNA assembled WiFi device inside of our brain effectively using it as a "mobile" storage medium? Probably not only that, but also for doing true multi-task administration in the real world scope.
:)
Just think how quickly one could hack wireless access points around them or a beowolf cluster of brain activity via peer-to-peer. That should rack up some SETI@Home work units completed in no time!
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Great... Now when the compter blows up, I'll get dysentery.
Will the new computers built of this material be more suceptable to virus attack!
For problems, seek only the simplest solution, complexity brings with it more problems.
Michael Faraday did this years ago (use google). The only thing these guys brought to the table is the capacitance reactivity factor is about 43% of the original magnitude of Faraday's experiments.
As a scientist in this field, I can say that this technology is still pretty wild and untested. You won't see anything come out of this for at least a decade, and even then, it probably won't get any further than Faraday's original result (he was eaten by a bio-thermo-electrolitic legume, aka a synthetic bean).
this will put phrase 'my computer has died' into a completely new light ;-)
I can just the future.
"Humanity wiped out by terrible strain of life threatenning virus -- but it makes great video cards."
Finally a use for the moon. A clean room.
Could you imagine getting sick and having to sign an NDA and non contagion agreement?
What is the life expectancy of the components? From the article it seems to me (disclaimer: IANAMolecularBiologistOrNanoEngineer) that the organic component is not required after the "wires" are in place but will the DNA auto-repair any damage to the wire?
Couldn't a virus (biological, not computer) be used to re-write the DNA strand that is used to construct the devices, to make different components for sinister purposes?
Is it paranoia if they really are out to get you?
Music is everybody's possession.
It's only publishers who think that people own it.
Fuck Beta
~John Lenno
Further refinement of the technique is required before full scale production would be efficient
/. include some sentence like this. I'm sortof patting myself on the back here when I say this, but hats off to the chemical engineers who actually do the work here. Chemical engineers are an important stepping stone between "oh, cool" and full-scale production, but hardly ever get a mention. In fact, most people have no idea what chemical engineers do, even though you probably scarcely have an item around you that doesn't owe its existence in part to chemical engineering.
It seems like a lot of the "science with potentially awesome applications" posts that get made to
A better process would be to adapt the proteosynthesis process for creating micro-polypeptide clusters that are circuit elements with highly specific binding sites for self assembly. A DNA sequence would encode an mRNA sequence that is passed to a ribsome-like micro-factory. An alphabet of tRNA units would carry heavily modified amino-acids and provide both the electrical and structural of properties of the polypeptide. Different polypetides might make transistors, autonomous clock circuits, chemical-to-electrical battery subunits, wires, tees, etc.
Part of the DNA sequence would encode binding sites that are highly specific. Each electrical component would have a unique code on each terminal that only binds with the component that it connects to in the circuit. By labelling all the terminii of the components with these specific binging patterns, you the potential for self-assembly. To make a complex circuit, you make separate batches of each component, then mix the batches together and they self-assemble into the circuits. Thus, a soup of appropriately labeled transistors and wires would self-assemble into a soup of full-adder circuits.
The use of larger-scale binding sites would enable hierarchical self-assembly of self-assembled micro-components (e.g., a soup of 1-bit full-adder circuits might self-assemble into a 8-bit full-adders, or 8-bit full-adders might bind to a gated accumulator registers, etc.)
I doubt this technology would let you create a 64-bit processor - the binding-site combinatorics get too ugly. But it might let you create RAM, RFID circuits, or small CPUs (e.g., the Intel 8080 only needs 6000 transistors)
Two wrongs don't make a right, but three lefts do.
Michael Crichton's books are both good and original. Unfortunately, the original parts are not good, and the good parts are not original.
evil math within Nature's Cubic Creation!
I'm impressed by the ability to make components, but I think that creating structures of many components may prove to be the more difficult problem.
As an example, it might not be difficult to design a 1-bit memory cell that can be assembled this way, but how do you make an array of them that is exactly some number of cells on a side, and then attach the interface circuitry to the edges? This would seem to require giving the little buggers the ability to count (or measure), and then change their beheviour when a desired state had been attained.
The last time I checked, we know a fair amount about how living cells build proteins, but the problem of how the cells know when to build them and how to stick them together has barely been scratched.
Its not how long or when that should scare you, its the fact that resistance is futile.
[I can picture a world without war, without hate. I can picture us attacking that world, because they'd never expect it]
Imagine what the possibilities are here.
Were I in control of this style of circuit manufacture, I would look into creating artifical neurons -- a small CPU core would provide the basic multiply-accumulate-threshold logic on the neuron. Other multiply-accumulate circuits at the synapses or dendrites would provide long-term adaptation functionality needed for learning.
The advantage of a neural net appraoch is that it can work with an inexact network. Standard digital electronics are logically fragile for the most part (i.e., they break if you replace an OR gate with an AND or swap two data lines). Digital electronics depends on highly repeatable manufacturing processes that create exact interconnect topologies. In contrast, neural nets are robust to any-to-any connection topologies and use various long-term adaptation schemes to reinforce or attenuate the connections that are needed.
Thus, you could create a soup of neural node cores, dendrite fragments, axon fragments and synapse units that would self-assemble into a gelatinous brain-mass. Plop the mass on top of a set of electrical interconnects and then train the blob to do what ever you want it to do. Moreover, these nano-fragment brains would be about roughly 10-100 times smaller in each dimension (about a thousand to a million times smaller in volume) than their cellular equivalents.
It could get interesting if we can create human-brain level neural net blobs that fit in a 1 cubic centimeter volume. Neural gel-packs, here we come.
Two wrongs don't make a right, but three lefts do.
They already have joined component built with this method.. but not on the megascale we're used to in modern procesors.
I think circuitry built using this approach would have to be thought about in a fundementally different way.
Fairly obviously (I think) large scale structures like the processors we know and love today would be very dificult to create using this organic approach. A better approach might be to just go for creating very dense, very connected but essentially amorphous 'mats' of computing resource (neuron like units perhaps ??) and treating the whole thing as more like an FPGA than a traditional structured computing device. So the problem becomes not how to grow these things in a particular shape.. but how to persuade the shapeless mass to do something useful.
Would it possible to have these things assembled by protein structures that deliberately mutate at each assembly to provide binding sites that uniquely identify each processing element. That might be a start.