UCLA Explores Nano-Bio Interactions (posted 7/7/09)
Researchers at UCLA and the California NanoSystems Institute (CNSI), along with colleagues in academia and industry, have taken a role in examining the current understanding of the nano-bio interface. The team has worked to identify the potential risks of engineered nanomaterials and to explore design methods that will lead to safer and more effective nanoparticles for use in a variety of treatments and products.
More than 800 products-including clothes, skin lotions and cleaning products-claim to have at least one nanocomponent, and therapeutic nanocarriers have been designed for targeted drug delivery inside the human body. Human exposure to nanomaterials raises some important questions, including whether these nano-bio interactions could have adverse health effects.
In a research review published in the July issue of Nature Materials, the team provides a comprehensive overview of current knowledge on the physical and chemical properties of nanomaterials that allow them to undergo interactions with biological molecules and bioprocesses.
“What we have established here is a blueprint that will serve to educate the first generation of nanobiologists,” said Andre Nel, Ph.D., leader of the team and chief of the division of nanomedicine at the David Geffen School of Medicine at UCLA and the CNSI.
Despite advances in nanoscience, relatively little is known about the intracellular activity and function of engineered nanomaterials, an area of study particularly important for the development of effective and safe nanoparticle drug delivery systems. Much of the current knowledge derives from the study of tagged or labeled nanoparticles and their effects on cells after cellular uptake, without any detailed understanding of what these interactions may lead to, whether good or bad.
The review article examines the variety of ways in which nanomaterials interface with biological systems and presents a roadmap of the physical and chemical properties of the materials that could lead to potentially hazardous or advantageous interactions at the nano-bio interface. A better understanding of the biological impact, combined with appropriate stewardship, will allow for more informed decisions about design features for the safe use of nanotechnology.
In addition to Nel, the team included Tian Xia, a researcher in UCLA's nanomedicine division; Eric Hoek, UCLA associate professor of civil and environmental engineering; Lutz Mädler of the University of Bremen; Darrell Velegol of Penn State University; Ponisseril Somasundaran of Columbia University; Fred Klessig of Pennsylvania Bio Systems; Vince Castranova of the National Institute for Occupational Safety and Health; and Mike Thompson of FEI Co.
“We are committed to ensuring that nanotechnology is introduced and implemented in a responsible and safe manner,” said Nel, who also directs the Center for Environmental Implications of Nanotechnology, which is funded by the National Science Foundation and the U.S. Environmental Protection Agency and is headquartered at the CNSI. “Based on our rapidly improving understanding of nano-bio interactions, we have done a thorough examination of the literature and our own research progress to identify measures that could be taken for safe design of nanomaterials. Not only will this improve the implementation and acceptance of this technology, but it will also provide the cornerstone of developing new and improved nanoscale therapeutic devices, such as drug-delivering nanoparticles.”
The review article spotlights several important research advancements:
- A classification of the interactions when nanomaterials contact and bind to biological systems will help scientists understand how manmade materials may react when exposed to cells, tissues and various life forms in different natural environmental contexts.
- When nanomaterials enter a biological fluid (e.g., blood, plasma or interstitial fluid), the materials' surface may be coated with proteins. Understanding how these protein layers change the properties of the nanomaterials and the ways in which they interact in the body can provide valuable information on how to alter the protein coatings to allow for targeted delivery of nanomaterials to specific tissues, such as in cancer treatments.
- Physicochemical properties such as size, charge, shape and other characteristics could greatly affect the ability of nanomaterials to enter a cell; this could determine whether a material can be useful in nanomedicine applications or could cause harm if taken in by life forms in an ecosystem or food chain.
- Nanoparticles can elicit a wide range of intracellular responses, depending on their properties, concentrations and interactions with biological molecules. These properties and their relationships to cellular function can induce cellular damage or induce advantageous cellular responses, such as increased energy production and growth.
“Instead of waiting for knowledge to unfold randomly, we can already begin to view the events at nano-bio interface as a discoverable scientific platform that can be used for setting up a deliberate inorganic-organic roadmap to new, better and safer products,” said Nel. “What we can identify by understanding the rules that shape the nano-bio interface will have a massive impact on the ability to develop safe nanomaterials in the future.”
Visit www.ucla.edu for more information.