NanomedicineCenter.com

Magnetic nanoparticles detox blood

Lead (plumbum, lat.) is the most dangerous heavy metal out there and it’s extremely toxic, especially for children. Increased amounts of lead in blood trigger a medical condition known as plumbism or saturnism. The condition may cause irreversible damage to the nervous, renal and cardiovascular system.
Lead is mainly ingested through food. Acute lead poisoning rarely ever happens — it’s more of a gradual process that may last for years until symptoms start to show (anemia, memory loss, muscle weakness).
The current treatment option is chelation therapy, which causes many side effects — while the chelates “kill” the “bad” elements, they do the same to vital materials that the body needs. It seems that this method will be a matter of history.

Researchers from Korea have discovered a new technique which is based on a fluorescence receptor that selectively and strongly binds to lead ions. How does this actually work? The receptor is bound to magnetic nanoparticles and can be removed in a simple magnet-powered hemodialysis procedure. By using magnetic particles, the researchers were able to remove almost 96 % of the lead ions from blood samples mixed with lead in vitro.
When a lead ion binds to such a “lead receptor”, the receptor’s fluorescence is “switched on”, causing it to glow. The receptor binds to no other metal ions, only lead. Perhaps a selective lead detector could be used for detoxification, as well as detection. The scientists synthesized a derivative of such a lead detector and also equipped the molecule with a special chemical “anchor”. They used this anchor to attach the receptor molecules to the surface of magnetic nanoparticles made of silicon-dioxide-coated nickel.

The technique could work just like hemodialysis — the blood gets taken out of the patient, it gets processed, and then reintroduced to the patient as totally “cleaned”. No vital materials would be harmed during the whole process.

The research is published in Angewandte Chemie.

New nanoparticle developed for angiogenesis research

Angiogenesis is the process of creating new blood vessels, and it plays a vital role in the recovery process for many diseases such as cancer or cardiovascular diseases.
At the Skaggs School of Pharmacy and Pharmaceutical Sciences (UCLA), scientists have developed a novel synthetic nanoparticle for noninvasive imaging of angiogenesis.

Nanomedicine has the potential to revolutionize the treatment process of these diseases, and the research team has developed a biodegradable nanoprobe to target a biological marker known to modulate angiogenesis.
“One challenge of nanoparticles has been the difficulty in targeting where they go, because of the properties of size and structure,” said Adah Almutairi, PhD, the leader of the research. “Either they are unable to diffuse into tissue, because the nanoparticles are too large, or – if too small – they clear out of the system too rapidly.” Almutairi also said that the developed nanoprobe is completely nontoxic, and it’s very much biodegradable. That’s what makes it attractive for the commercial sector.
“This particle is small enough to easily circulate – about ten to 12 nanometers in size, where most nanoparticles are about 50 nanometers,” Almutairi said. “We also ‘decorated’ it with targeting groups in a novel way so that it can recognize diseased tissue.”

The paper is published in Proceedings of the National Academy of Sciences.

Source: ucsd.edu

Scientists found a way to combat cholesterol problems

The holidays are finally over. We’ve enjoyed in all the things that they bring, especially the food. However, all the food that we’ve eaten boosted our blood cholesterol levels all the way to the top. These things seem inevitable, because we, humans, just can’t control ourselves when we eat. We never think of the consequences…

However, scientists from the Northwestern University have come up with a solution — synthetic high-density lipoprotein (HDL), the “good” cholesterol. It could help combat chronically high cholesterol levels and the deadly heart disease that often results. The synthetic HDL is 18 nanometers in diameter, a size similar to natural HDL.
Scientists developed a synthetic HDL and showed that their nanoparticle version is capable of irreversibly binding cholesterol. It’s completely based on gold nanoparticles.

“We have designed and built a cholesterol sponge. The synthetic HDL features the basics of what a great cholesterol drug should be,” said Chad A. Mirkin, one of the researchers. “Drugs that lower the bad cholesterol, LDL, are available, and you can lower LDL through your diet, but it is difficult to raise the good cholesterol, HDL. I’ve taken niacin to try and raise my HDL, but the side effects are bad so I stopped. We are hopeful that our synthetic HDL will one day help fill this gap in useful therapeutics.”

They started building the synthetic HDL based on a gold nanoparticle as the core. Then they layered on a lipid that attaches to the gold surface, then another lipid and last a protein, called APOA1, the main protein component of naturally occurring HDL.

The details are published in the Journal of the American Chemical Society.

Source: northwestern.edu

Gold nanoparticles shine again

Scientists from Massachusetts Institute of Technology (MIT), by using gold nanoparticles and infrared light, have designed a drug delivery system that allows multiple drugs to be released in a controlled manner. The system could be used in treatments which require more than one drug.

“With a lot of diseases, especially cancer and AIDS, you get a synergistic effect with more than one drug,” said Kimberly Hamad-Schifferli, one of the authors.

Devices like this can be found on the market already, but have some disadvantages when compared to the new one. For example, the time of releasing the drug must be programmed into the device — it cannot be controlled from outside the patient’s body. This new device (system) allows complete external control and supports up to 3 or 4 drugs.

This new method takes advantage of the fact that when gold nanoparticles are exposed to infrared light, they melt and release drug payloads attached to their surfaces.
Nanoparticles of different shapes respond to different infrared wavelengths, so “just by controlling the infrared wavelength, we can choose the release time” for each drug, said Andy Wijaya, the lead author of the study.

Source: web.mit.edu