Nanosurface [Repels/Attracts] [Oil/Water/Dirt] (and Conducts Electricity Too)

They could also make the surfaces attract or repel oil. And given the right materials, the fibers can even conduct electricity.

The potential applications are numerous. For example, if the fibers repel water, oil and dirt, then they’d create almost self-cleaning surfaces; windows would stay clear longer.

By making them attractive, they’d make a good anti-fog coating, since they’d pull at water droplets and make them flatten out on a surface.

Or what about this?

“… researchers found that the attracting surface does the same thing to coiled-up strands of DNA. When they put droplets of water containing DNA on the fibers, the strands uncoiled and hung suspended from the fibers like clotheslines.”

Since they can conduct electricity, organic LEDs can be embedded in the surface and powered without wires.

Aby.T.Joseph

grandmastermind@hotmail.com

Quantum Dots Glow Where Cancer Cells Grow

Looking for cancer cells is like searching for a pin in a basket of needles. Tiny, glowing particles called quantum dots may someday make it easy to precisely locate malignant masses. When injected into the body, they would drift around until encountering cancerous tissue. The deadly cells would latch onto a special coating on the glowing dots. Attached to the inside of the cancer cells, the bright particles would serve as a beacon that would show doctors where the deadly disease has spread.

Scientists from SUNY Buffalo, Johns Hopkins, and Zhejiang University worked together to develop and test this somewhat new type of medical nanotechnology. Many other research groups (everyone and their mother) have recently completed similar studies, but this one is a particularly elegant example.

Quantum dots are extremely tiny semiconductor crystals. Some of them glow very brightly when struck with ultraviolet radiation and photographed with a confocal microscope. Postdoctoral scholar Ken-Tye Yong and graduate student Jun Qian coated some of those shiny quantum dots with transferrin, a protein that pancreatic cancer cells quickly gobble up. They attached an antibody that sticks to pancreatic cancer cells onto a second batch of the bright nanoparticles.

Semiconductor nanoparticles have several other very distinct advantages. First off, they don’t fade quickly. Their competition, fluorescent molecules made from carbon, get bleached by light very quickly and thus become useless. Second, quantum dots come in a zillion varieties. Since so many scientists have studied them, it is almost easy to make them and attach things to them, and build ones with exactly the right features.

Equipped with two sets of customized particles, the international team led by Professors Paras N. Prasad and Indrajit Roy of SUNY Buffalo tested their ability to identify several types of pancreatic cancer.

The coated nanoparticles would consistently act as a glowing stain that clearly identified the deadly cells. Quantum dots without the special coating could did not stick to, enter, or otherwise label them.

The research paper that describes this work appears in the June issue of the Journal of Physical Chemistry B. It mentions that their next step will be to test the quantum dots in mice. It may be a while before this imaging method is used in people. The quantum dots are currently made with the element Cadmium, which is very toxic. Before they are injected into humans, scientist will need to prove that they can be made safe. This could be accomplished either by creating a coating that prevents the toxic metal from causing any damage, or replacing it altogether.

Aby.T.Joseph

grandmastermind@hotmail.com

Fluorescent Nanoparticles Identify Bacteria

Scientists at the University of Florida have designed tiny fluorescent particles that can be used to rapidly identify bacteria by color coding them. This could be useful for preventing bioterror attacks, rapidly diagnosing infections, and testing food for contaminants.

Current technology, including the infamous Gram Stain, can only divide bacteria into two broad categories. The new method can determine the exact species and sort various types of bacteria on the same microscope slide.

Professor Weihong Tan and his students created nanoparticles with three different colors, blue for Escherichia coli, orange for Stapphylococcus aureus, and purple for Samonella typhimurium. They attached different antibodies to each of the colored nanoparticles.

Antibodies are proteins that stick to one and only one thing. In this case, each nanoparticle contained antibodies that would latch onto a single type of bacteria.

When they put all three particles into a broth with three different types of bacteria, the nanoparticles color coded those bacteria so that they could be very quickly identified by looking at them through a confocal microscope. Tan and his team reported their findings in the current issue of Bioconjugate Chemistry, a journal that deals with attaching biological molecules like antibodies to other molecules, surfaces, and nanoparticles.

Aby.T.Joseph

grandmastermind@hotmail.com