The science of nanotechnology is rapidly moving from its early beginnings in electronics, computers and telecommunications into the expanding field of biomedical nanotechnology. Dr. Nie has been a leader in the nanomedicine field, and has developed semiconductor nanoparticles called quantum dots, which can be bound to particular genes and proteins and used as markers for molecular diagnostics and drug delivery.
"Biomedical nanotechnology is leading to major advances in molecular diagnostics, therapeutics, molecular biology and bioengineering," Dr. Nie says. "Scientists have begun to develop functional nanoparticles that are linked to biological molecules such as peptides, proteins and DNA."
By virtue of their miniature size nanoparticles assume special properties that distinguish them from larger particles, including the ability to emit light in different colors and to act as fluorescent tags. This makes them highly suitable as contrast agents for magnetic resonance imaging (MRI), positron emission tomography (PET) or as fluorescent tracers in optical microscopy. They also may be useful as structural scaffold in tissue engineering.
Although nanoparticles are similar in size to biomolecules such as proteins and DNA, nanoparticles can be humanly engineered to have specific or multiple functions. In a process called "multiplexing, bioconjugated quantum dots of different sizes can be embedded in tiny polymer beads and finely tuned to tag a multitude of proteins or genetic sequences.
In particular, says Dr. Nie, medical applications for namoparticles will focus on cancer, cardiovascular disease, and neurodegenerative diseases, such as Alzheimers. For example, nanoprobes using quantum dots that are chemically bound to particular genes and proteins can rapidly analyze biopsy tissue from cancer patients to monitor the effectiveness of drug therapy, or utilized as "smart bombs" to deliver controlled amounts of drugs into genetically classified tumor cells.
"Nanomedicine is a priority in the recently released new Roadmap of the NIH," Dr Nie points out. "We expect Emory and Georgia Tech to be institutional leaders in nanomedicine."