Hamad-Schifferli talks with ScienceWatch.com and
answers a few questions about this month's Fast Breaking
Paper in the field of Chemistry.
Article Title: Selective Release of Multiple DNA
Oligonucleotides from Gold Nanorods
Authors: Wijaya, A;Schaffer, SB;Pallares,
Journal: ACS NANO, Volume: 3, Issue: 1, Page: 80-86, Year:
* MIT, Dept Biol Engn, 77 Massachusetts Ave, Cambridge, MA
* MIT, Dept Biol Engn, Cambridge, MA 02139 USA.
* MIT, Dept Mech Engn, Cambridge, MA 02139 USA.
* MIT, Dept Chem Engn, Cambridge, MA 02139 USA.
* Brown Univ, Div Biol & Med, Providence, RI 02912
* Univ N Carolina, Dept Chem, Chapel Hill, NC 27599 USA.
Why do you think your paper is highly cited? Does
it describe a new discovery, methodology, or synthesis of
One of the most exciting prospects of nanotechnology is that nanoparticles
can act as a handle by which one can control nanoscale processes,
particularly biological ones. Due to their size, nanoparticles can reach
places where such processes are typically inaccessible to external
manipulation, such as inside individual cells.
The allure of externally controllable "nanoantennas" and "nanobots" is that
they can control the inner workings of biological machines by releasing
molecules or signals that can dictate biomolecular and cellular behavior.
In addition, nanoparticles can carry a large payload and be decorated with
molecules that can target them to specific types of cells.
View/download accompanying figures and
Due to their physical properties, they can also be simultaneously tracked
and imaged. Consequently, nanotechnology has held great promise for
enhancing existing biological systems as well as engineering new
capabilities in biology.
This paper was the first to use gold nanorods for multichannel control of a
biological process. We used lasers to selectively heat different nanorods
to release two different species independently. This technique we developed
has unique advantages for improving combination therapy, the use of drug
cocktails/mixtures, which is used to treat many complex diseases. The paper
describes a new methodology.
Would you summarize the significance of your paper in layman's
Complex diseases such as
HIV and cancer require a mixture of drugs, or a
so-called "drug cocktail," to treat them. For the best efficacy of the
drug, each of the drugs in the mixture must be released at specific
times and in specific amounts. Our technique using gold nanorods is a
way to control the release of more than one drug precisely, to release
the right amount of each drug at specific times.
How did you become involved in this research, and were there any
problems along the way?
We have always been interested in using nanoparticles for biological
applications, and this was one of the ways that
nanotechnology can be exploited for biology. The
biggest challenge was overcoming surface problems of the nanorods,
since, due to their small size, they are dominated by their surfaces. If
the surfaces of the nanorods are not "clean," they tend to clump in
biological solutions, preventing any sort of handling. We had to come up
with a new way to clean up their surface chemistry first before
attempting to do this research.
Where do you see your research leading in the future?
This paper was simply a proof-of-principle experiment, to show that
selective release could be done. We are now using this technique for things
such as cancer therapy and medical applications, in addition to using it as
a tool for studying biological behavior on the molecular and cellular
Kimberly Hamad-Schifferli, Ph.D.
Department of Mechanical Engineering
Department of Biological Engineering
Massachusetts Institute of Technology (MIT)
Cambridge, MA, USA Web