Feature Stories

NCMN  Members  Celebrate  Research  Breakthroughs  in  Materials  and  Nanoscience !
....at the Nebraska Center for Materials and Nanoscience

NSF award aids Pannier's work on gene delivery tool

Angela Pannier, a UNL biological systems engineer, is using nanotechnology to develop a gene delivery tool. (Craig Chandler / University Communications)
Angela Pannier, a UNL biological systems engineer, is using nanotechnology to develop a gene delivery tool. (Craig Chandler / University Communications)

Employing DNA that codes for genes to correct genetic problems, treat disease or aid healing holds tremendous potential, but finding an effective, safe method of delivering genes to cells remains a significant hurdle. A UNL engineer is using nanotechnology to develop a gene delivery tool that could unleash the power of gene therapy.

Angela Pannier, assistant professor of biological systems engineering, recently earned a five-year, $419,051 Faculty Early Career Development Program Award from the National Science Foundation to continue her research. These prestigious awards, also known as CAREER awards, support junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent teaching and the integration of education and research.

Pannier is developing 3-D nanostructured surfaces that use the spaces between nano-sized columns to hold large amounts of DNA, similar to a toothbrush loaded with toothpaste. Touching the nanostructure to the cell unloads the DNA.

She’s also designing the surfaces so that touching the ends of the columns, or bristles, to the cell alters it in ways that make it more or less receptive to receiving genes. The genes could come from the nanostructured surface itself, or elsewhere, such as the bloodstream.

“We hypothesize that if you put a cell down on a nanostructured surface that’s just loaded with DNA, you are providing the cells more opportunity to take up the genetic material,” Pannier said. “We also think that if, at the same time, you are making an optimal environment for the cells, they’ll take up even more DNA. The combination of that is incredibly novel and has huge potential.”

This gene delivery method allows cells to use the gene to make beneficial proteins without incorporating the gene into its chromosome and could provide a longer-term therapeutic solution than drugs. This approach also is safer than methods that use viruses, which integrate genes into the cells’ DNA structure or cause secondary reactions, Pannier said.

The therapeutic potential is enormous, she added. For example, medical devices could incorporate these nanostructured surfaces to deliver genes that promote integration with bone following a hip implant; reduce inflammation after placing a heart stent to unclog a blocked artery; or promote tissue growth in tissue engineering procedures.

It also could be used to deliver genes to cure genetic diseases, such as cystic fibrosis or hemophilia, or even treat some cancers, cardiovascular conditions, and other diseases.

The nanostructure surfaces also could be used in biotechnology research and in sensors to help detect molecules in the environment, such as toxic gases or microbial contaminants.

Pannier, a member of the university’s Center for Nanohybrid Functional Materials, is collaborating with UNL electrical engineers and center members Mathias Schubert and Eva Franke-Schubert to fabricate and study the nanostructured surfaces.

“We think that (these surfaces) are going to change the field of biomaterials and drug and gene delivery because you can deliver so many different things. It’s unlimited, really,” she said.

With her CAREER award, Pannier also is developing courses to enhance UNL’s biomedical engineering curriculum by emphasizing learning through primary literature and hands-on laboratory exercises. She also will provide research experiences for high school and undergraduate students, as well as design outreach workshops and curriculums for high school teachers to use in their classrooms. — Gillian Klucas, Research and Economic Development

POWERFUL PULL TO NEW MAGNETS-Supply Problems with vital
RARE-EARTH METALS attract new magnet-making methods 
by Mitch Jacoby, C&EN Chicago on January 7, 2013

David J. Sellmyer, a physics professor at the University of Nebraska, Lincoln, agrees. “In this field, that would be like setting out to hit a grand slam home run.” He explains that Nd2Fe14B magnets’ outstanding strength has made them indispensable to modern computer disk drives, a variety of large and tiny audio speakers, and many types of motors and motor generators crucial to the performance of hybrid automobiles and electricity-generating windmills.

The high strength of Nd2Fe14B and other rare-earth-based magnetic materials such as samarium cobalt (SmCo5) leads to powerful yet relatively small and lightweight magnets. That strength, which is often expressed as a “magnetic energy product,” can be on the order of 56 megagauss-oersteds (MGOe). A common refrigerator magnet, based on iron, is less than 1 MGOe.

One new research thrust in the bottom-up category takes its cue from the inner workings of rare-earth magnets. In Nd2Fe14B, for example, the transition metal is the source of the high magnetization. The rare-earth component is responsible for the high value of a property known as magnetocrystalline anisotropy, which is related to a magnet’s resistance to becoming demagnetized. The underlying idea is to engineer composite materials that combine high magnetization and high aniso­tropy components.

“The trick is bringing these components together on a very short length scale—about 10 nm,” Sellmyer says. At that scale, the two components are intimately tied to each other magnetically, or what experts in this field describe as strongly exchange coupled. The concept has been around since the 1990s, Sellmyer points out, but it has been difficult to implement. Despite recent advances in synthesizing a large variety of nanoparticles, researchers have found it challenging to control the size, crystal structure, and phase purity of exchange-coupled nanoparticles. One source of that challenge is a high-temperature treatment, usually above 500 °C—it causes nanoparticles to coalesce and grow to large size.

To overcome the size and structure problems, Sellmyer, Balamurugan Balasubramanian, and coworkers, including the University of Delaware’s George C. Hadjipanayis, developed a heat-treatment-free cluster deposition technique for making nanoparticles. In one application of that method, the team fabricated new rare-earth transition-metal nanoparticles by sputtering an yttrium-cobalt target. That process, which resembles atomic-scale sandblasting, generates vapors of Y and Co atoms that cool and directly aggregate into uniform-sized crystalline YCo5 and Y2Co17 nanoparticles measuring less than 10 nm in diameter. The proof-of-concept study shows that the method can be used to fabricate well-ordered magnetic nanoparticles for further analysis (Nano Lett., DOI: 10.1021/nl200311w).

The team also applied the method to making rare-earth-free hafnium-cobalt nanomagnets and nanocomposites of HfCo7 encapsulated in an FeCo phase. Like the Y-Co particles, the HfCo7 nanoparticles are also well ordered and tend to be less than 10 nm in diameter. Sellmyer points out that this sputter-based cluster methodology for making nanocomposites can be readily adapted to produce other types of permanent-magnet alloys including next-generation high-performance magnets (Appl. Phys. Lett., DOI: 10.1063/1.4753950).

Dr. David Sellmyer awarded Louise Pound-George Howard Distinguished Career Award Louise Pound-George Howard Distinguished Career Award

Posted on 4/20/2012, College of Arts and Sciences

Since it was established in 1990, the Louise Pound-George Howard Distinguished Career Award has recognized individuals who have made an exceptional contribution to the university during their careers. These contributions have been through teaching, research, public service, administration or through a combination of these factors. The honored individuals also reflect a long-standing commitment to the university. ...more

Dr. David Sellmyer, founding director of the Nebraska Center for Materials and Nanoscience and George Holmes University Professor of physics and astronomy — Sellmyer’s research interests have focused on condensed matter physics and nanoscience. He has (co-)authored and edited more than 530 research articles, chapters and reviews, and eight books. He is a fellow of the American Physical Society, an honorary member of the State Key Magnetism Laboratory, Chinese Academy of Sciences, and won Outstanding Research and Creative Activity awards from the University of Nebraska and Sigma Xi. At UNL he has organized and pushed many collaborative research and education initiatives including a new nanoscience research facility that was completed this spring. It is in large thanks to his nearly 40-year record of dedication, vision, and continuing service that UNL now enjoys national prominence as one of the country’s leaders in materials and nanoscience research.

Dr. Mathias Schubert, University of Nebraska-Lincoln associate professor of electrical engineering, has been elected a fellow of the American Physical Society. Election to the fellowship is limited to no more than one-half of 1 percent of the society's membership.

The APS has 14 divisions and nine topical groups covering all areas of physics research. There are six forums that reflect the interests of its 43,000 members in broader issues and eight sections organized by geographical region.

Schubert was cited by the APS council at its November meeting for the "development of generalized ellipsometry and the invention of the Optical Hall Effect, and their transformative potential for industrial characterization of materials properties." Those materials could be developed into such things as liquid crystal displays or semiconductor device structures. read further...

Dr. Xia Hong NSF Early Career Award

Hong to use CAREER award to research nanoscale materials

Released on 04/30/2012, Today@UNL
University of Nebraska–Lincoln

Dr. Xia Hong, assistant professor of physics and astronomy and a researcher in UNL’s Materials Research Science and  Engineering Center, earned a five-year, $600,000 Faculty Early Career Development Program Award from the National Science Foundation to continue her research.

For decades, scientists have been squeezing more power out of today’s silicon-based electronics, which are approaching the material’s fundamental limits. To continue advancing, researchers are exploring existing materials for unique properties at the nano-level and fabricating new nanomaterials with multifunctional properties. Many materials exhibit unusual physical, chemical or biological properties at the nanoscale that are not found at the larger macro level.

With her award, Hong will combine two oxides to create a multiferric nanomaterial with both magnetic and ferroelectric properties. Ferroelectric materials have positive and negative polarization directions. Applying electricity can reverse the polarization. In a multiferric material, electricity also can control magnetism. ...more