Microelectromechanical based systems

Columbia engineering innovative hand-held lab-on-a-chip could streamline blood testing worldwide. Successfully tested in Rwanda, mChip diagnoses infectious diseases like HIV and syphilis at patients’ bedsides; new device could streamline blood testing worldwide

New York, NY — Samuel K. Sia, assistant professor of biomedical engineering at Columbia Engineering, has developed an innovative strategy for an integrated microfluidic-based diagnostic device—in effect, a lab-on-a-chip—that can perform complex laboratory assays, and do so with such simplicity that these tests can be carried out in the most remote regions of the world. In a paper published in Nature Medicine online on July 31, Sia presents the first published field results on how microfluidics—the manipulation of small amounts of fluids—and nanoparticles can be successfully leveraged to produce a functional low-cost diagnostic device in extreme resource-limited settings.

Sia and his team performed testing in Rwanda over the last four years in partnership with Columbia’s Mailman School of Public Health and three local non-government organizations in Rwanda, targeting hundreds of patients. His device, known as mChip (mobile microfluidic chip), requires only a tiny finger prick of blood, effective even for a newborn, and gives—in less than 15 minutes—quantitative objective results that are not subject to user interpretation. This new technology significantly reduces the time between testing patients and treating them, providing medical workers in the field results that are much easier to read at a much lower cost. New low-cost diagnostics like the mChip could revolutionize medical care around the world.

“We have engineered a disposable credit card-sized device that can produce blood-based diagnostic results in minutes,” said Sia. “The idea is to make a large class of diagnostic tests accessible to patients in any setting in the world, rather than forcing them to go to a clinic to draw blood and then wait days for their results.”

Sia’s lab at Columbia Engineering has developed the mChip devices in collaboration with Claros Diagnostics Inc., a venture capital-backed startup that Sia co-founded in 2004. (The company has recently been named by MIT’s Technology Review as one of the 50 most innovative companies in the world.) The microchip inside the device is formed through injection molding and holds miniature forms of test tubes and chemicals; the cost of the chip is about $1 and the entire instrument about $100.

Sia hopes to use the mChip to help pregnant women in Rwanda who, while they may be suffering from AIDS and sexually transmitted diseases, cannot be diagnosed with any certainty because they live too far away from a clinic or hospital with a lab. “Diagnosis of infectious diseases is very important in the developing world,” said Sia. “When you’re in these villages, you may have the drugs for many STDs, but you don’t know who to give treatments to, so the challenge really comes down to diagnostics.” A version of the mChip that tests for prostate cancer has also been developed by Claros Diagnostics and was approved in 2010 for use in Europe.

Sia’s work also focuses on developing new high-resolution tools to control the extracellular environments around cells, in order to study how they interact to form human tissues and organs. His lab uses techniques from a number of different fields, including biochemistry, molecular biology, microfabrication, microfluidics, materials chemistry, and cell and tissue biology.

###

Sia was named one of the world’s top young innovators for 2010 by MIT’s Technology Review for his work in biotechnology and medicine, and by NASA as one of 10 innovators in human health and sustainability. In 2008, he received a CAREER award from the National Science Foundation that included a $400,000 grant to support his other research specialty in three-dimensional tissue engineering. A recipient of the Walter H. Coulter Early Career Award in 2008, Sia participated in the National Academy of Engineering’s U.S. Frontiers of Engineering symposium for the nation’s brightest young engineers in 2007. He earned his B.Sc. in biochemistry from the University of Alberta, and his Ph.D. in biophysics from Harvard University, where he was also a postdoctoral fellow in chemistry and chemical biology.

The mChip project has been supported by funding from the National Institutes of Health and Wallace Coulter Foundation.

Columbia Engineering

Columbia University’s Fu Foundation School of Engineering and Applied Science, founded in 1864, offers programs in nine departments to both undergraduate and graduate students. With facilities specifically designed and equipped to meet the laboratory and research needs of faculty and students, Columbia Engineering is home to NSF-NIH funded centers in genomic science, molecular nanostructures, materials science, and energy, as well as one of the world’s leading programs in financial engineering. These interdisciplinary centers are leading the way in their respective fields while individual groups of engineers and scientists collaborate to solve some of society’s more vexing challenges. www.engineering.columbia.edu/

Contact: Holly Evarts holly@engineering.columbia.edu 212-854-3206 Columbia University

Despite their initial focus on national economic competitiveness, the nanotechnology research initiatives now funded by more than 60 countries have become increasingly collaborative, with nearly a quarter of all papers co-authored by researchers across borders.

Researchers from the two leading producers of nanotechnology papers – China and the United States – have become each nation’s most frequent international co-authors. Though Chinese and U.S. researchers now publish roughly the same number of nanotechnology papers, the U.S. retains a lead in the quality of publications – as measured by the number of early citations.

“Despite ten years of emphasis by governments on national nanotechnology initiatives, we find that patterns of nanotechnology research collaboration and funding transcend country boundaries,” said Phillip Shapira, study co-author and a professor in the School of Public Policy at the Georgia Institute of Technology. “For example, we found that U.S. and Chinese researchers have developed a relatively high level of collaboration in nanotechnology research. Each country is the other’s leading collaborator in nanotechnology R&D.;”

Caption: Researcher Phillip Shapira is co-author of a study assessing the increasingly collaborative nature of the worldwide nanotechnology research effort. Credit: Georgia Tech. Usage Restrictions: None.

The findings were part of a new study of nanotechnology publishing reported Dec. 2 in the online edition of the journal Nature. The research was sponsored by the National Science Foundation-supported Center for Nanotechnology in Society at Arizona State University (CNS-ASU). Sparked by programs such as the National Nanotechnology Initiative (NNI) in the United States, leading industrial nations have launched nanotechnology research programs that invested more than $8 billion in public funds in 2008 alone. China, Germany, Japan and Korea are among the many countries that have launched major governmental programs to develop their national nanotechnology capabilities as part of efforts to boost future economic growth. “There is widespread anticipation that nanotechnology will be a critical component in addressing global challenges in such areas as energy, environment, health care, security and sustainability,” explained Shapira, who is also a professor of innovation at the University of Manchester.

“At the same time, nanotechnology may be a key driver in the next wave of technology-led economic growth and investment. Governments around the world are hoping that their often massive investments in nanotechnology R&D; will lead not only to economic, but also to significant societal returns.”

Though the revolutionary advances that nanotechnology promises are still off into the future, Shapira noted that the investments made so far have led to “a noticeable shift toward innovation in the past few years as companies are beginning to market a wide range of products and devices whose performance has been enhanced by nanoscale science and engineering.”

The study was conducted by Shapira and collaborator Jue Wang, an assistant professor at Florida International University. It used data mining techniques to study funding acknowledgements that have been available since 2008 in the Web of Science – one of the leading international databases of scientific publications. Shapira and Wang analyzed more than 91,000 papers published worldwide between August 2008 and July 2009.

They found that although researchers from 152 nations were represented in the survey, just 15 countries represented 90 percent of the papers. The top four countries by author affiliation were the United States (23 percent), China (22 percent), Germany (8 percent) and Japan (8 percent). Papers authored by researchers from more than one nation – which constituted 23 percent of those examined – were assigned to more than one country.

Though the United States and China now produce approximately the same number of papers, the U.S. maintains significant advantages.

“Compared with Chinese counterparts, papers authored by U.S. researchers still have a substantial lead in terms of citation quality and U.S. corporate activity in nanotechnology innovation remains rather larger,” Shapira said. “However, Chinese quality is improving and an increasing number of Chinese companies are becoming engaged in developing and commercializing nano-enabled products.”

The study analyzed the funding sources cited in a sub-set of 61,300 papers that were supported by grants. The National Natural Science Foundation of China was the top funder, with more than 10,200 publications representing 16.7 percent of all sponsored papers. Second was the U.S. National Science Foundation with 6,700 publications. Rounding out the top five were the Ministry of Science and Technology of China, the European Union’s R&D; programs, and the U.S. Department of Health and Human Services – which includes the National Institutes of Health.

Eight sponsors saw at least 10 percent of the papers they funded garner five or more citations within a year of publication – the study’s definition of an “early-citation” paper. This group is led by four U.S. agencies: the National Institutes of Health, the National Science Foundation, the Department of Energy, and the Department of Defense.

About three percent of U.S. papers reported co-funding from the Chinese National Natural Science Foundation, while a similar proportion of Chinese papers report co-funding from the U.S. National Science Foundation.

“Although these numbers are still low relative to purely nationally-funded papers, they signal a significant trend as China has taken over from European countries as America’s leading international collaborator by volume in nanotechnology research,” Shapira explained. “China’s scientific relationships do, of course, extend beyond the United States, and China has emerged as the hub for nanotechnology research collaboration in Asia.”

The study also found that sponsors concentrating their funding in fewer institutions had lower research impact as measured by early citation counts.

“Our starting hypothesis is that when groups from multiple institutions vie for funding, there is increased competition, review processes are less partial, and there are more opportunities to select the most improving projects,” Shapira explained.

With increasing budget pressures, growth in nanotechnology funding appears unlikely. How should countries invest their limited funding for greatest benefit?

“One way would be to foster more high-quality international collaborations, perhaps by opening funding competitions to international researchers and by offering travel and mobility awards for domestic researchers to increase alliances with colleagues in other countries,” the researchers suggested in their paper. ###

Contact: John Toon jtoon@gatech.edu 404-894-6986 Georgia Institute of Technology Research News

OAK RIDGE, Tenn., — Thin layers of oxide materials and their interfaces have been observed in atomic resolution during growth for the first time by researchers at the Center for Nanophase Materials Sciences at the Department of Energy’s Oak Ridge National Laboratory, providing new insight into the complicated link between their structure and properties.

“Imagine you suddenly had the ability to see in color, or in 3-D,” said the CNMS’s Sergei Kalinin. “That is how close we have been able to look at these very small interfaces.”

The paper was published online in ACS Nano with ORNL’s Junsoo Shin as lead author.

A component of magnetoelectronics and spintronics, oxide interfaces have the potential to replace silicon-based microelectronic devices and improve the power and memory retention of other electronic technologies.

A new scanning tunneling microscopy and low energy electron diffraction technique developed at Oak Ridge National Laboratory captured this 50 nm x 50 nm image of an oxide surface. Each bright dot is a single atom of material.

However, oxide interfaces are difficult to analyze at the atomic scale because once the oxides are removed from their growth chamber they become contaminated. To circumvent this problem, ORNL researchers led by Art Baddorf built a unique system that allows scanning tunneling microscopy and low energy electron diffraction to capture images of the top layer of the oxide while in situ, or still in the vacuum chamber where the materials were grown by powerful laser pulses. Many studies of similar oxide interfaces utilize a look from the side, typically achieved by aberration corrected scanning transmission electron microscopy (STEM). The ORNL team has used these cross-sectional images to map the oxide organization.

However, like a sandwich, oxide interfaces may be more than what they appear from the side. In order to observe the interactive layer of the top and bottom oxide, the group has used scanning tunneling microscopy to get an atomically resolved view of the surface of the oxide, and observed its evolution during the growth of a second oxide film on top.

“Instead of seeing a perfectly flat, square lattice that scientists thought these interfaces were before, we found a different and very complicated atomic ordering,” said Baddorf. “We really need to reassess what we know about these materials.”

Oxides can be used in different combinations to produce unique results. For instance, isolated, two oxides may be insulators but together the interface may become conductive. By viewing the atomic structure of one oxide, scientists can more effectively couple oxides to perform optimally in advanced technological applications such as transistors.

Kalinin says the correct application of these interface-based materials may open new pathways for development of computer processors and energy storage and conversion devices, as well as understanding basic physics controlling these materials.

“In the last 10 years, there has been only limited progress in developing beyond-silicon information technologies,” Kalinin said. “Silicon has limitations that have been reached, and this has motivated people to explore other options.”

Atomic resolution of interface structures during oxide growth will better enable scientists to identify defects of certain popular oxide combinations and could help narrow selections of oxides to spur new or more efficient commercial applications.

This research is supported by the U.S. Department of Energy, Office of Science.

The Center for Nanophase Materials Sciences at ORNL is one of the five DOE Nanoscale Science Research Centers supported by the DOE Office of Science, premier national user facilities for interdisciplinary research at the nanoscale. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE’s Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos national laboratories. For more information about the DOE NSRCs, please visit nano.energy.gov.

ORNL is managed by UT-Battelle for the Department of Energy’s Office of Science.

Contact: Katie Freeman freemanke@ornl.gov 865-574-4160 DOE/Oak Ridge National Laboratory