DailyDirt: Observing Really Small Biological Events

from the urls-we-dig-up dept

It's not easy to study living things. Biological cells are made up of an insanely complex mixture of chemicals that somehow self-organize and react to produce stuff like sugars, proteins... and thoughts. Any help to visualize these biological processes is much appreciated, even if there's no Nobel prize for biology. Here are just a few more cool ways to measure what's going on in our bodies at the cellular level.

• The use of silicon nanocrystals that glow (as quantum dots) could be useful for medical imaging. These nanocrystals can absorb and emit light in the near-IR, and these particles have caused no ill effects in monkeys 3 months after being injected with relatively large doses. [url]
• To measure the temperature of a single cell, nanodiamonds could serve as tiny thermometers. These diamond-based thermometers are also pretty sensitive, able to detect fluctuations of 0.05 Celsius inside a cell (and as low as 0.0018 Celsius in less noisy environments). [url]
• Photoluminescent nanoparticles have been shown to glow -- even through more than 3 centimeters of skin -- and produce high-contrast images of biological tissue. To minimize biological incompatibility, these nanocrystals have an outer shell made of calcium fluoride (a material found in bones and teeth). [url]

If you'd like to read more awesome and interesting stuff, check out this unrelated (but not entirely random!) Techdirt post via StumbleUpon.

Filed Under: biology, biotech, calcium fluoride, gfp, medical imaging, nanocrystal, nanoparticles, nanotech, photoluminescent, quantum dot, sensors, thermometer

DailyDirt: Metallic Royalty

from the urls-we-dig-up dept

Noble metals, such as gold and platinum, get their name from their rarity in occurrence and because they don't easily oxidize or corrode when exposed to the atmosphere. It takes a highly corrosive mixture of hydrochloric acid and nitric acid (aka, "aqua regia") to dissolve gold or platinum. In fact, Aqua regia (which is Latin for "regal water") is named for its ability to dissolve "noble" metals. Due to their desirable properties, noble metals have found use particularly in jewelry making as well as chemical catalysts. Here are a few examples of some recent findings related to noble metals.

• Researchers at Northwestern University have figured out how to use cornstarch instead of toxic cyanide to selectively extract gold from raw materials and electronic waste. Apparently, alpha-cyclodextrin (a cyclic starch fragment made of six glucose units) works best for isolating gold. [url]
• University of Helsinki researchers have concluded that silver nanoparticles aren't any more toxic than silver ions for aquatic ecosystems. Since silver nanoparticles have anti-bacterial and anti-fungal properties, they are used in many consumer goods like clothing, cosmetics, food storage containers, and medical devices. However, there have been concerns about the increased amount of silver being washed into the environment. [url]
• Scientists at Hokkaido University have developed a platinum nanoparticle catalyst that can keep fruit from ripening prematurely while in storage. Ripening fruit releases ethylene gas, which then accelerates the ripening of other fruit. The platinum nanoparticles were able to effectively oxidize ethylene even at zero degrees Celsius, which is the temperature required in cold storage warehouses. [url]

If you'd like to read more awesome and interesting stuff, check out this unrelated (but not entirely random!) Techdirt post via StumbleUpon.

Filed Under: catalyst, chemistry, cornstarch, cyclodextrins, fruit, gold, nanoparticles, noble metals, platinum, silver

DailyDirt: Contrary To Popular Belief, Diamonds Aren't Forever

from the urls-we-dig-up dept

There are plenty of good reasons why gold is a valuable element that has been used as money instead of other substances in nature. Diamonds might have been an interesting form of carbon to use in a monetary system, but diamonds don't actually last forever. Here are just a few quick links on diamonds.

• Candle flames can create diamond particles very briefly, but the diamonds are burned away in the process. About 1.5 million diamond nanoparticles are created every second as a candle burns, actually. [url]
• Diamond is thermodynamically unstable, but it was only recently discovered that it can actually lose mass slowly under UV light. Physicists found this out when they couldn't make a diamond-based UV laser that lasted for more than 10 minutes... [url]
• Diamonds have a high index of refraction that makes them sparkle. But there are possibly other forms of carbon that could be more sparkly -- if only they could be synthesized. [url]
• To discover more interesting science-related stuff, check out what's currently floating around the StumbleUpon universe. [url]  

By the way, StumbleUpon can recommend some good Techdirt articles, too.

Filed Under: candle, diamond, nanoparticles, refraction, uv laser