Nano Bullets for Ovarian Cancer

Nano Bullets for Ovarian Cancer

A nano-sized drug capsule designed to seek-and-destroy malignant cells shows signs of being able to significantly shrink ovarian cancer tumors. The researchers behind the novel drug, Mansoor Amiji at Northeastern University and MIT’s Robert Langer, say the secret is in the packaging: a pH-sensitive nanoparticle that encapsulates the therapeutics, delivering them directly to cancer sites in mice and suppressing tumor growth. The researchers reported their success in the journal Cancer Chemotherapy and Pharmacology.

“The main challenge in ovarian cancer treatment is lack of selectivity for tumor cells versus normal cells,” says Amiji, a pharmaceutical scientist and the study’s principal investigator. “Many approaches have devastating side effects, attacking a lot of normal cells like hair follicle and gastrointestinal cells.” Ovarian cancer is a tempting target for the technology because it is particularly difficult to treat and often has a high relapse rate, Amiji says, but the nanoparticle system could be applicable to other forms of cancer.

To avoid such side effects and hone drug delivery, Amiji and his colleagues looked for ways to exploit key characteristics of tumor cells. The environment around most tumors is acidic, having lower pH levels than the rest of the body. Levels are even more acidic inside tumors due to lack of blood and lactic acid buildup. They deduced that a pH-sensitive drug package could thus selectively target the tumor cells.

The drug-carrying vessel needs to be small enough to pass through a tumor’s membrane and yet resilient enough to not be broken down by the body’s immune cells before reaching the tumor site. So the researchers engineered a nanoparticle out of pH-sensitive, biodegradable polymers. Much like a suitcase which could only be opened with a specific combination, this vessel could only be “unlocked” in the presence of low pH levels exhibited by tumor cells. Once unlocked, the vessel dissolves, releasing its drug contents specifically to cancer cells.

Other existing cancer therapies employ similar nano vessels for drug delivery. The most common are liposomes: naturally-derived, spherical vesicles that package drugs, carrying them across tumor membranes into cancer cells. However, these drug carriers run the risk of getting taken up by macrophages before getting to the tumor. Other potential drug carriers more resistant to the body’s natural defenses have been shown to have toxic side effects. Amiji and his colleagues hoped their nanoparticle would not only decrease toxicity, but also boost drug efficiency by more effectively evading the body’s immune system.

Live animal models put the theory and design to the test. The team packed their pH-sensitive nanoparticle with paclitaxel — a widely used cancer drug — and injected it into mice with ovarian cancer tumors. Other mice received injections of the same drug package minus pH sensitivity, while yet others received the drug alone (without a nanoparticle shell). Each group received only one dose of their respective treatments. A control group received no treatment at all.

Four weeks after the injections, mice with pH-sensitive treatments had tumors half as big as those treated with paclitaxel alone, and were slightly smaller than tumors treated with nano-packaged paclitaxel that was not pH-sensitive, suggesting a more effective delivery system. These same mice exhibited no measurable side effects: blood cell counts and body weight remained unchanged, and few mice were lethargic during treatment.

Continue reading the whole story by clicking on the Headline this is truely remarkable story.

Sharply Tuned Nanostrings Work At Room Temperature

Sharply Tuned Nanostrings Work At Room Temperature

Using a fast, low-cost fabrication technique that allows inexpensive testing of a wide variety of materials, Cornell researchers have come up with nanoscale resonators — tiny vibrating strings — with the highest quality factor so far obtainable at room temperature for devices so small.
The work is another step toward “laboratory on a chip” applications in which vibrating strings can be used to detect and identify biological molecules. The devices also can be used as very precisely tuned oscillators in radio-frequency circuits, replacing relatively bulky quartz crystals.

When you strike a bell or pluck a guitar string, it will vibrate within a small range of frequencies, centering on what is called the resonant frequency. Quality factor, or Q, refers to how narrow that range will be. It is defined as the ratio of the resonant frequency to the range of frequencies over which resonance occurs. A radio receiver with high-Q circuitry, for example, will be more selective in separating one station from another.Cornell researchers have already used vibrating strings and cantilevers to detect masses as small as a single bacterium or virus. Resonant frequency depends on the mass of a vibrating object (a thick guitar string has a lower pitch than a thin one). If a nanoscale vibrator is coated with antibodies that cause a virus or some other molecule to adhere to it, the change in mass causes a measurable change in frequency. In a high Q nanostring, the researchers say, a small change in mass will produce a much more noticeable shift.

The new nanostrings, made by graduate student Scott Verbridge and colleagues in the laboratories of Harold Craighead, Cornell professor of applied and engineering physics, and Jeevak Parpia, professor of physics, are made of silicon nitride under stress. By controlling the temperature, pressure and other factors as the film is deposited, the experimenters can cause the silicon nitride to be, in effect, stretched.

Congratulations Scott his is a major break thru I can not wait to see a working prototype!

Hot prospects for cooler chips

Hot prospects for cooler chips

The difficulty of keeping computer chips cool is one of the most immediate challenges for the IT industry. Researchers at IBMs Zurich lab are using nano-scale technologies to make self-contained water-cooling systems that are much smaller and can handle much higher power densities than the air-cooled copper heatsinks in use today.

Nanoscale devices are made of components that measure less than 100nm. A nanometre is equivalent to one billionth of a metre.
Dr Bruno Michel, manager of advanced thermal packaging research at the Zurich lab, said the paste between the chip and the heatsink, called the thermal interface material (TIM), currently accounts for 50 percent of the thermal resistance of chip-cooling systems. The TIM is needed because the silicon chip and the copper heatsink have different thermal expansion coefficients, so they can not be directly joined together.

This is a must read article and make sure to let me know what you think.

Nano-projector turns phone into a cinema

Nano-projector turns phone into a cinema

A tiny colour projector designed to be used with mobile phones, handheld devices and PDAs has successfully passed its first batch of tests.

Israel-based Explay says its nano-projector engine is a hundred times smaller and more efficient than rival technology.

The projector, little larger than a matchbox, will take images from a portable device and display them at any size up to 35ins on a wall or screen.

What a great use of this new technolgy I was totaly impresssed with the article and am glad they have made it so far in such a short amount of time.Be sure to read the rest.

Self-powered hydrogen sensors

Nano World: Self-powered hydrogen sensors

Nanotechnological, inexpensive sensors that can detect invisible, odorless hydrogen leaks and sound the alarm wirelessly could help safeguard future vehicles and refueling stations based on the gas, experts told UPI’s Nano World.
Intriguingly, the sensors have the ability to power themselves by harvesting energy from slight vibrations. This means they could operate continuously without batteries or maintenance when affixed to cars, refrigerators, pumps, motors or any other vibrating machine, the researchers added.

The chemical reaction hydrogen cars run on is remarkably simple. Just combine hydrogen gas with oxygen and you get energy and water — and none of the dirty mix of toxins and global warming gases burning gasoline spews forth. The cleanliness of hydrogen is in large part why government and industry support for hydrogen vehicles has reached into the billions of dollars.

The problem is hydrogen is odorless, invisible and potentially explosive. Researchers at the University of Florida at Gainesville funded by NASA have developed hydrogen sensors designed to work together in the dozens or hundreds to overcome this hurdle.

You will need to have sensors all over the place — if there is a leak, you can see which ones light up, and where the leak is, and how quickly it is spreading. That way you can shut off valves and avoid a major problem,” said researcher Steve Pearton, a materials engineer.

The sensors, currently the size of a deck of cards, employ rods of zinc oxide only nanometers or billionths of meters wide coated with platinum catalyst. Extremely tiny electrical currents are passed through each rod, and the more hydrogen surrounds these whiskers, the more conductive they become, to effectively detect hydrogen in the air. The researchers also developed wireless transmitters to broadcast signals out from the sensors, as well as ways to power the devices either through conventional solar cells or piezoelectric energy harvesters that convert vibrations into electricity.

You need lots of hydrogen sensors to detect leaks, but you don’t want to have to maintain them or change the battery every couple of months,” said researcher Jenshan Lin, an electrical engineer. “Our sensor can operate completely independently