National Science Foundation |
Directorate for Engineering (ENG)
Division of Chemical, Bioengineering, Environmental, & Transport Systems (CBET)
CBET Award Achievements (Formerly "CBET Nuggets")
Notable Accomplishments from CBET Awards
Collaborative Research: Locking Nanoparticles
Sergiy Minko - Clarkson University
Igor Luzinov - Clemson University
Collaborators at Clarkson University in New York and Clemson University in South Carolina
are developing superparamagnetic nanoparticles whose properties can be switched on and off
through external stimuli so that they can be used in a range of biological and medical
applications. This is important for applications where the adsorption of particles on
various surfaces needs to be turned on and off during various stages of a process.
Background: There is rapidly increasing
interest in nanoparticles used as delivery vehicles in various biological and medical
applications, for stabilization of emulsions and foams, and regulation of rheological and
optical properties of suspensions. All the applications are related to well-controlled
interactions between neighboring nanoparticles as well as between nanoparticles and their
host environment. Significant advances in the development of the fundamental background
for the understanding of particle behavior and in applications of the nanoparticles and their
assemblies in modern technologies rely on the extension of the particles' behavior toward
stimuli responsive properties using light, magnetic fields and electrical fields.
Nanoparticles with tunable interparticle interactions can be used for reorganization of
particles (aggregation/disaggregation, adsorption/desorption, stabilization/destabilization
of emulsions, inversion of emulsions) upon chemical changes in their environment and/or
exposure to external fields. These materials will create new opportunities to regulate
and control behavior in complex "intelligent" systems and could be useful for many
technologies and processes such as separation, mass transport, medical diagnostics, drug
delivery systems, coatings, and sensors.
Results: The research teams at Clarkson University in New York and Clemson University in South Carolina have developed a novel method for the surface modification of magnetic nanoparticles with an amphiphilic diblock copolymer. This method resulted in the synthesis of nanoparticles which can be self-assembled into rod-like structures upon "magnetic click" - a pulse of external magnetic field. Upon the magnetic signal the rod-like structures are locked and remain unchanged in aqueous dispersions with no external magnetic field. However, the rod-like structures can be unlocked and the particles can be disassembled upon other external signals (for example, by adding an acidic solution). This intelligent behavior of the nanoparticles controlled by external signals could find a broad range of important applications in various technologies from magnetic fluids to biotechnologies and medicine.
Scientific Uniqueness: The developed magnetic
material has been previously unavailable. The known magnetic liquids form
self-assembled structures in a magnetic field. Integrity of the structures is
preserved only by the external magnetic field and, thus, by consumption of energy. The
ability of the newly developed materials to form and stabilize the structure by a pulse of a
magnetic field is unique.
This project addresses the NSF Strategic Outcome Goals, as described in the NSF Strategic Plan 2006-2011, as follows:
Primary Strategic Outcome Goal: (1) Discovery: This research has discovered a novel kind of magnetic dispersions with unique stimuli-responsive properties.
(1) Discovery Category:
Secondary Strategic Outcome Goal: (2) Learning: The project involves training and research of undergraduate students, graduate students and post-docs. They have received training in synthesis and characterization of nanoparticles, utilization of the polymers for surface modification of nanoparticles, polymer grafting, light scattering, and atomic force microscopy. In general the project helps strengthen the training of students in the areas of magnetic nanoparticles and surface science. The project provides ample opportunities to integrate research and education through the cross-disciplinary student training in research labs, and scientific seminars. The results from the project will be incorporated into undergraduate and graduate classes taught by PIs.
(2) Learning Categories:
- Undergraduate Education and Undergraduate Student Research
- Graduate Education and Graduate Student Research
- Postdoctoral Education and Fellowships
This Award Achievement represents potentially Transformative Research: The developed novel materials have promising applications in engineering, biotechnology and medicine. In the long term, the proposed magnetic material could serve as a platform for the development of a wide range of new energy-efficient functional materials, processes and devices which explore the discovered locking mechanism for colloidal dispersions of the hybrid magnetic nanoparticles.
The Intellectual Merit of this research: This particular proposal is focused on responsive nanoparticles capable of reorganization in an external magnetic field, which can turn on interactions between the particles themselves or between particles and their environment. The interaction remains unchanged even after removal of the external magnetic field due to the specially tailored polymer shell of the nanoparticles. This mechanism is termed here the "locking mechanism." The "locking particles" can be unlocked by applying external stimuli such as temperature, changes in pH, chemical reaction, or strong shear forces.
The Broader Impacts of this research include:
(1) Broadening participation of underrepresented groups: The project involves training and research of female students in the area of chemical engineering.
(2) Benefits of the proposed activity to society: The obtained results are expected to have substantial impact on nanoscience and nanotechnology fields involving nanoparticle technologies and design of complex energy-efficient functional materials and devices. The magnetic responsive particles will be used for a range of important medical and technical applications where the specific versus nonspecific particle interactions can be switched on in the external magnetic field. The project has an important educational role for training undergraduate and graduate students.
(3) Advancing discovery and understanding while promoting teaching, training, and learning: In general the project helps strengthen the training of students in the areas of colloid and surface science. The project provides opportunities to integrate research and education through cross-disciplinary student training in research labs, and scientific seminars. The PIs involve both undergraduate and graduate students in the proposed research and train them to gain:
(i) expertise in nanofabrication techniques,
(ii) familiarity with modern concepts in materials and colloidal chemistry,
(iii) the ability to synthesize and characterize nano-materials,
(iv) the ability to run experiments, gather data, and make discoveries, and
(v) the ability to write scientific papers and make effective technical presentations.
(4) Broadening participation of underrepresented groups: The project involves training and research of female students in the area of chemical engineering.
(5) Disseminaton of results to enhance scientific and technological understanding: The work of this research group appeared in the journal Nature Nanotechnology, which has a very broad readership and high impact factor. In addition, the PIs have given research overviews and general seminars on sustainability and energy to the public to foster an understanding of the issues involved in finding future alternatives for petroleum-based fuels. These have included, but are not limited to, presentations to the local Rotary Club, local high school, and University Pre-Game Scholar Showcase and the Centripetals Seminar Series, which are promoted as scholarly presentations targeted to and heavily subscribed by the general population.
Areas of Emphasis (Themes) for FY 2010 Highlights included in this research project:
(1) Interdisciplinary, high-risk, and potentially transformative
(2) Speeds the translation of promising fundamental research into innovations that can be commercialized
(3) Promotes innovative energy technologies
(4) Enhances health and quality of life
(5) Advances new materials and devices -- such as silicon microelectronics that exploit properties at the quantum level required to realize computing capacity beyond the limits suggested by Moore's Law (SEBML)
CBET Program Director - Particulate and Multiphase Processes
|NSF Award Number:||0756461|
|Award Title:||Collaborative Research: Locking Nanoparticles|
|PI Name:||Sergiy Minko|
|Institution Name:||Clarkson University; Potsdam, NY|
|Program Element Code:||1415|
CBET Award Achievement:
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This Award Achievement was Updated on 5 October 2010.