Mchip Diagnoses Infectious Diseases Like HIV And Syphilis At Patients' Bedsides; New Device Could Streamline Blood Testing Worldwide

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.

Contacts and sources:

Holly Evarts
Columbia University 

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. http://www.engineering.columbia.edu/

Remnants of 19th-Century Village Beneath Central Park

Columbia University archaeologist Nan Rothschild walks her dog in Central Park each morning, not far from where William G. Wilson used to live—more than 150 years ago.

Archaeologist Nan Rothschild talks about the Seneca Village Project. (2:32)

Credit: Columbia University

Rothschild has unearthed what is left of Wilson’s home, as well as other remnants of Seneca Village, the first community of African American property owners in New York City. The village existed from the 1820s until 1857, when its inhabitants were evicted to make way for the creation of Central Park.

“Seneca Village was autonomous,” said Rothschild, director of museum studies at Columbia and research professor at Barnard College. “It had its own institutions, so its residents could live free from the everyday burdens of racism. It was a refuge. In a way, it was both in the city and out of the city—located about three miles from the densely settled portion of Manhattan.”

Seneca Village was located within New York’s famous grid street system between 81st and 89th Streets and 7th and 8th Avenues, in what is now a portion of Central Park just east of Central Park West.

The Seneca Village Project, started in 1999, is managed by Rothschild and her co-directors, Diana Wall, of City College of New York and CUNY Graduate Center, and Cynthia Copeland, of New York University. Preliminary work included research of historical documents and soil analysis. Excavation, which began two months ago, is being conducted by the three scholars, as well as 10 undergraduates from colleges across New York City. The excavation portion of their research will conclude on July 29, but research of the artifacts will continue.


The team utilized ground-penetrating radar to study the area long before the dig. In fact, the radar showed them what they thought were artifacts concentrated in one place. They later learned that the radar had, in fact, found the walls of Wilson’s home. The discovery of his 19-foot by 21-foot home was, according to Rothschild, an accident. After indentifying the walls of the structure, the team excavated metal roofing, a stoneware beer bottle, kitchen utensils and clothing remnants from Wilson’s home. They also discovered ceramics and butchered animal bones near the home of another villager named Nancy Moore.

“Seneca Village was a middle-class African American community,” said Rothschild. “Our notions of what African Americans were like in the 19th century do not usually include class variations. In time, the village came to include Irish immigrants, which is counter to our ideas about how these two groups got along in that era.”

During its more than three decades, Seneca Village grew into a community of nearly 300 people. Two-thirds of its villagers were of African descent, while the rest were predominantly of Irish descent. The community included a school, as well as three churches—one of which was racially integrated.

“We know a great deal about Seneca Village from historic documents, but the archaeology gives us evidence of the fabric of peoples’ lives,” said Rothschild. “What foods—meat especially—they ate, what dishes they chose for their homes, how their homes were built. These are all details that are completely missing from the historical record and are really important in understanding, for example, how expressions of class—so visible in the purchase of home furnishings—were manifest in the village.”

The research would not have been possible without the extensive support of the New York City Department of Parks and Recreation and the Central Park Conservancy.

The excavation and identification of artifacts was funded by the National Science Foundation, National Geographic, the Durst Foundation, PSC-CUNY, the Richard Gilder Foundation and private contributions.

Contacts and sources:
Columbia University

Engineers Develop Material That Could Speed Telecommunications

Researchers at Columbia Engineering School have demonstrated that light can travel on an artificial material without leaving a trace under certain conditions, technology that would have many applications from the military to telecommunications.

In this illustration, light hits Kocaman’s and Wong’s specially engineered material without leaving a trace. The actual material is no thicker than one hundredth of the diameter of a strand of hair.

Credit: Columbia Engineering School

In a study published July 10 on Nature Photonics’s website, Serdar Kocaman, an electrical engineering Ph.D. candidate, and Chee Wei Wong, associate professor of mechanical engineering, demonstrated how an optical nanostructure can be built that controls the way light bounces off it.

When light travels, it bends—in technical terms, it disperses and incurs “phase,” an oscillating curve that leaves a trail of information behind it. Those oscillations show an object’s properties, such as shape and size, which can identify it. However, light hits Kocaman’s and Wong’s specially engineered material without leaving a trace.

Every natural known material has a positive refractive index: when light hits it, the light bends or refracts. The researchers engineered a structure in which they etched tiny holes, creating a material known as a “photonic crystal” which behaves as though it has zero index—light can travel with an ultrafast velocity in this environment. The material, a coating no thicker than one hundredth of the diameter of a strand of hair, has properties that don’t occur in nature.

“We’re very excited about this. We’ve engineered and observed a metamaterial with zero refractive index,” said Kocaman. “Even in a vacuum, light propagates with a phase advancement. With the zero phase advancement, what we’ve seen is that the light travels through the material as if the entire space is missing.”

“We can now control the flow of light, the fastest thing known to us,” Wong said. “This can enable self-focusing light beams, highly directive antennas, and even potentially an approach to hide objects, at least in the small scale or a narrow band of frequencies.”

The zero-index material was based on a negative refractive index material and a superlattice material demonstrated consecutively in 2008 and 2009 by the scientists. In the new paper Kocaman and Wong, together with colleagues, demonstrate that the optical phase advancement can be controlled and even eliminated under certain conditions.

The study was led by Wong and Kocaman, in collaboration with scientists at the University College of London, Brookhaven National Laboratory, and the Institute of Microelectronics of Singapore. It is the first time phase and zero-index observations have been made on both a photonic chip scale and at infrared wavelengths. These photonic chip circuits can be helpful in fiberoptic networks.

This research was supported by grants from the National Science Foundation and the Defense Advanced Research Projects Agency.

Contacts and sources:

Columbia University