A field that is developing alongside nanobiotechnology is something that you might call nanotoxicology. There is a fear that the same properties that make nanosize particles potentially helpful in fields like drug delivery might also make them harmful. For example, nanoparticles--because of their size--promise to finally break through the body's defensive blood-brain barrier and deliver therapeutics directly to the brain. However, researchers--and, increasingly, government regulators -- are concerned that not enough is known about possible unintended consequences of nanoparticles swirling around up there.
For example: A group of researchers, writing in the European Journal of Pharmaceutics and Biopharmaceutics, is proposing a method of setting up a cell model of the blood-brain barrier to use as a tool for screening nanoparticles' interactions. Establishing a model is a first step in determining that ever-present question in nanotech: "Is it safe?"
But here's the thing about nanotoxicity, and nanotech in general. It's about harnessing properties that, if left alone, could be harmful. However, if used properly and engineered correctly, a potentially toxic particle can become a powerful tool.
Here's an example: A group of nanotox researchers at North Carolina State University looking into how nanoparticles interact with living things might have also, as a side benefit, made a discovery with applications for drug delivery.
"We wanted to find a good, biologically relevant way to determine how nanomaterials react with cells," Nancy Monteiro-Riviere, professor of investigative dermatology and toxicology, said recently in a release. "When a nanomaterial enters the human body, it immediately binds to various proteins and amino acids. The molecules a particle binds with will determine where it will go."
The binding, itself, affects the particle's behavior inside the body, she said. So, amino acids and proteins that coat a nanoparticle can actually change its properties enough to reduce toxicity and to enhance its ability to deliver drugs to targeted cells. Tweak the nanoparticle's size and surface characteristics, and that will determine what kinds of materials it will bond with. Then it's just a matter of observing the "fingerprint" of a particular nanomaterial to predict how it will behave. "That in turn will give us a better idea of which nanoparticles may be useful for drug delivery, and which ones may be hazardous to humans or the environment," Riviere said. Article