Dr. Nanotech vs. Cancer What exactly would a nanosensor to detect such proteins look like? To turn a nanowire into a transistor, the researchers bring each of its ends into contact with metal wires so that a current can be passed through it. They then position an electrode close to the nanowire. Charging this electrode alters the conductivity of the nanowire, turning it “on” and “off”—all familiar stuff to any electrical engineer.
Heath then transforms his nanowire transistors into tiny biosensors. Say, for instance, that one nanowire is to act as a sensor for a particular protein. The researchers coat the surface of the wire with antibodies that will stick to the target protein but not to other molecules. When proteins bind to the antibodies, they interact with the electrons traveling in the nanowire’s surface layer, altering its conductivity. If the wire is only a few nanometers thick, there is a significant—and measurable—change in its overall conductivity. “If the wire is really, really small,” says Heath, “instead of putting a voltage on it, we can put molecules on it, and a chemical event is what causes the transistor to switch.”

Dr. Nanotech vs. Cancer What exactly would a nanosensor to detect such proteins look like? To turn a nanowire into a transistor, the researchers bring each of its ends into contact with metal wires so that a current can be passed through it. They then position an electrode close to the nanowire. Charging this electrode alters the conductivity of the nanowire, turning it “on” and “off”—all familiar stuff to any electrical engineer.
Heath then transforms his nanowire transistors into tiny biosensors. Say, for instance, that one nanowire is to act as a sensor for a particular protein. The researchers coat the surface of the wire with antibodies that will stick to the target protein but not to other molecules. When proteins bind to the antibodies, they interact with the electrons traveling in the nanowire’s surface layer, altering its conductivity. If the wire is only a few nanometers thick, there is a significant—and measurable—change in its overall conductivity. “If the wire is really, really small,” says Heath, “instead of putting a voltage on it, we can put molecules on it, and a chemical event is what causes the transistor to switch.”

The New York Times > Health > Study Finds Doctors' Hours Affect Risks on Road: "Doctors in training were more than twice as likely to get in a car crash while driving home after working 24 hours or longer, compared with when they worked shorter shifts, according to a study conducted by Harvard Medical School."

Wired 13.01: Life, Reinvented: "But Endy does teach an IAP. This year his class is devoted to building counters - devices that count from, say, 1 to 32. That may not sound like much of a challenge for students at the world's most prestigious engineering school; in fact, it's the sort of thing a nerdy middle school kid would solder together. But here's the rub: The counters his students design won't be electronic, but biological. They won't be made of transistors, but DNA. And they won't be inserted into breadboards, but living bacteria."

BBC NEWS | Health | Pregnancy disorder detection hope: "Low levels of a key protein may help doctors to identify women at risk of pre-eclampsia mid-way through pregnancy, research suggests.
Scientists at the Beth Israel Deaconess Medical Center hope their findings will lead to a new screening test for the potentially fatal condition.
They found pre-eclampsia is associated with low levels of a protein in the urine linked to blood vessel growth."

Philadelphia Inquirer | 01/05/2005 | Like magic: A purifying powder can turn muddy water clear, and safe.: "The new powder, called PUR, contains chlorine but has other ingredients that give it two key advantages. PUR gets rid of toxic 'heavy metals,' such as arsenic and mercury, and it makes muddy water look clean - a key to winning acceptance from those who may be leery of aid from outsiders."

Science & Technology at Scientific American.com: Scientists Unravel How Geckos Keep Their Sticky Feet Clean: "The super sticky feet of geckos allow the animals to cling easily to nearly any surface. In fact, a single toe contains enough foot hairs, known as setae, to support the animal's entire body weight."

iPods Store Medical Images: "Two radiologists recently developed open-source software, called OsiriX, to display and manipulate complex medical images on the popular portable devices called iPods. "

iPods Store Medical Images: "Two radiologists recently developed open-source software, called OsiriX, to display and manipulate complex medical images on the popular portable devices called iPods. "