3D DNA-Directed Nanoassembly
If you're not satisfied with the materials provided by nature, why not build your own materials - from the atoms on up? Three-dimensional nanoassembly has now been accomplished by two different teams from Northwestern University and the Brookhaven National Laboratory.
"The crystal structures are deliberately designed," says Northwestern's Chad Mirkin, one of the materials scientists who pioneered DNA linking in the 1990s and a coauthor of one of today's reports. "This is a new way of making things."
Until now, attempts to program nanoparticle self-assembly in three dimensions has produced mostly disordered clumps. The two teams have overcome the problems involved by using longer DNA strands that give the particles more flexibility during crystal formation.
Here's how it works:
While the details of the Northwestern and Brookhaven systems differ, both pad out their DNA strands with sequences that act as spacers and flexors, in addition to complementary sequences on the DNA ends that bind particles together. The groups start by binding one of two types of DNA to gold nanoparticles. The DNA types are complementary to each other. These two pools of modified particles are then mixed and cooled. DNA strands with complementary DNA form a double helix, tying together their respective nanoparticles, while identical DNA strands act like springs to repel their respective particles. The spacers on each DNA strand, meanwhile, allow bound particles to twist and bend so each particle in the mix can bind the largest number of complementary particles.
The result is exactly what theory predicts: a crystal lattice in which each particle of one type is surrounded by eight of the others marking the corners of a cube.
(Gold nanoparticles programmed self-assembly
Sequences of DNA attached to gold nanoparticles (upper image) program the particles’ self-assembly into novel crystals (lower image). X-ray diffraction confirms the crystals--partly squashed by the electron microscopy that produced these images--to be perfect lattices of tens of thousands of particles.)
As far as I know, the first mention of trying to make something with individual atoms was in A Menace in Miniature, a 1937 story by early sf great Raymond Z. Gallun.
"With the Scarab as big as a beetle, I could make a Scarab as big as a sand grain. This second Scarab could build a miniature of itself, as big as a dust grain. The third Scarab could construct a fourth, bearing the same proportions as the first to the second, or the second to the third. And so on, down, to the limit imposed by the ultimate indivisibility of the atoms themselves."
(Read more about Gallun's ultra-microrobots)
While we're waiting for researchers to perfect self-assembly at the nano level, there are other methods. Nanoassembly can also be done by "hand" - or by "nanohand." Take a look at this remarkable video of a nanohand constructing a nanodevice with nanofibers.
From Researchers create three-dimensional structures using DNA-directed assembly via Smart Economy.
Scroll down for more stories in the same category. (Story submitted 2/5/2008)
Follow this kind of news @Technovelgy.
| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
you like to contribute a story tip?
Get the URL of the story, and the related sf author, and add
Comment/Join discussion ( 1 )
Related News Stories -
3D Printing Of Metallic Glass
Draw Circuits With Conductive Ink
'It's rewiring things... squeezing silver toothpaste in a ribbon along the printed circuitry.'
How To Encode The 'Memory' Of Materials
'Just jar it, and it falls into that structure like a rubber figure returning to shape.' - Samuel R. Delany, 1966.
Surface Film Repels All Bacteria
'Most gentlemen's and ladies' gloves nowadays were constructed of infinitesimal fabricules that knew how to eject dirt...'- Neal Stephenson, 1995
Technovelgy (that's tech-novel-gee!)
is devoted to the creative science inventions and ideas of sf authors. Look for
the Invention Category that interests
you, the Glossary, the Invention
Timeline, or see what's New.
I Want My 1928 Telestereo Hologram Now
'Instantly there appeared standing upon the disk, the image of a man...'
Memes Now Come From Neural Nets
'Your order said for him to be able to be able to work out twists on the gags in the file...'
Robot Dog Learns To Be Doggy From Real Dogs
'So we took pictures of Guzub making a Three Planets, and I could construct this one to do it exactly right down to the thousandth of a second.'
Unwanted Cruise Ships Huddle Together Out At Sea
'On the screen they passed in an endless, boundaryless flood of green specks...'
Sono Sion Electric Car Charges As You Drive
'It drew its power from six square yards of sunpower screens on its low curved roof.'
News Mood Filter Web Extension
'He adjusted the n, the r and b knobs, and hopefully anticipated a turn for the better...'
Fetal Lamb Rests In Artificial Womb
'... stewing warm on their cushion of peritoneum and gorged with blood-surrogate and hormones, the foetuses grew and grew...'
MIT Wants To Catch Interstellar Visitors
'INVESTIGATE MYSTERIOUS OBJECT ENTERING NEW CALEDONIA SYSTEM FROM NORMAL SPACE'
AutoX Sets Up Asia's Largest Robotaxi Center
'The robot cab seemed to know where it was going and, no doubt, the master machine from which it received its signals knew.'
E - Ink's Automatic Self Styling Color-Changing Dress
'The racks of gowns itched and quivered, their colors running into blurred pools.'
Soft Robots Use Kirigami Piezoelectric Sensor Skin
'A worthy opponent was the golem.'
Bosch Smartglasses Laser Paints AR Image On Your Retina
'Soon we'll be testing a system that projects directly on the retina of the eye.'
Maybe We Could Hibernate Until The Covid-19 Pandemic's End
'Cold-rest was a common last resort therapy for functional psychoses.'
Workplace Monitoring Hell, I Mean, Tool For Safe Distancing
'And here is the weirdest part -- I never see another employee the entire day.'
Patent Office Says AIs Cannot Be Inventors
'The real smart ones are as smart as the Turing heat is willing to let 'em get.'
Starlink Orbital Network Like Coruscant Traffic Jam
Vermin of the Sky? Or Internet access for all?
More SF in the News Stories
More Beyond Technovelgy science news stories