Interesting tech developments in nanotech, nanostructured materials, etc.
Ken Novak's Weblog
Saturday, November 22, 2003
: "Braun's team began their manufacturing process by coating a central part of a long DNA molecule with proteins from an E. coli
bacterium. Next, graphite nanotubes coated with antibodies were added, which bound onto the protein. After this, a solution of silver ions was added. The ions chemically attach to the phosphate backbone of the DNA, but only where no protein has attached. Aldehyde then reduces the ions to silver metal, forming the foundation of a conducting wire. To complete the device, gold was added. This nucleates on the silver and creates a fully conducting wire. The end result is a carbon nanotube device connected a both ends by a gold and silver wire." It functions as a transistor. The entire process is room temperature. 6:52:45 PM
Thursday, November 13, 2003
Progress in creating artificial virus: "While the project was based on widely known molecular biology principles, the breakthrough was in the short time — days instead of months or years — it took to construct the virus, said institute founder J. Craig Venter, one of the lead researchers. Researchers previously synthesized the polio virus from enzymes that naturally occurred in cells, but that process took three years and produced viruses with defects. The effort last summer by Venter and his colleagues took only two weeks from start to finish and created a viral DNA identical to the known genetic code, the researchers said... Even though the experiment involved a simple organism, the researchers suggested their work demonstrated the ability to quickly and accurately synthesize long segments of DNA that can serve as “a stepping stone to manipulating more complex organisms.” 10:44:33 PM
Tuesday, November 04, 2003
Gold "nano-bullets" shoot down tumours "The tiny silica particles are plated with gold and heat up when near infrared light (NIR) is shone on them. This kills the cancer cells... Body tissues are essentially transperant to NIR...
The Rice University team created nanoparticles from a non-conducting core of silica with a diameter of 110 nanometres and a 10 nm thick metal shell. Gold was used because it is biologically inert. When the nanoshells were added to human breast cancer cells in the test tube, and then exposed to both NIR, 100 per cent were killed, says West. "And we saw no changes in cell viability with just nanoshells or just the laser - it's a true on/off situation." The team also injected the nanoshells directly into the tumours of living mice and applied NIR. The tumours were destroyed within days. ..
The team has now engineered the nanoshells to specifically target tumour cells. In a recent study, submitted to Cancer Letters, they injected mice with nanoshells attached to an antibody that only binds to cancer cells. She says the tumours were "completely destroyed" and 150 days later the mice were alive and well with no tumour growth." The heat from the nanoshells makes holes in the cancer cell walls to kill them. 7:35:11 AM