Paper Strip Test Developed for Ebola, Other Diseases

Paper strip test to detect Ebola and other viruses. On the left is the unused device, opened to reveal the contents inside. On the right, the device has been used for diagnosis; the colored bands show positive tests. (Massachusetts Institute of Technology)

25 February 2015. Biological and engineering researchers at Massachusetts Institute of Technology designed a simple device that can test in the field for several viral diseases at once, including Ebola. The team from the labs of microbiologist Lee Gehrke and engineering professor Kimberly Hamad-Schifferli described the device earlier this month in the journal Lab on a Chip (registration required).

The MIT researchers sought a quicker and easier method for clinical teams in remote locations to diagnose infectious diseases, which as seen in the current Ebola epidemic, can be devastating to entire communities. Testing for Ebola now requires taking blood samples and sending them to labs for analysis, which identify the presence of Ebola genetic material, but takes time, expensive equipment, and skilled staff. In limited resource regions, these lab facilities are often few and far between.

In addition, clinicians in the field are often confronted with symptoms associated with multiple diseases. “As we saw with the recent Ebola outbreak, sometimes people present with symptoms and it’s not clear what they have,” says Hamad-Schifferli in a university statement. “We wanted to come up with a rapid diagnostic that could differentiate between different diseases.”

For their device, the researchers adapted lateral flow technology, a process trapping the specimen sample in an absorbent paper or polymer plastic strip, which then flows with capillary action to active particles that change color when exposed to the targeted protein or pathogen. Probably the most well-known example of lateral flow technology is the home pregnancy test that indicates the presence of a hormone closely associated with pregnancy.

In this device, the MIT team devised a simple process to test for three infectious diseases at one time. The device uses a paper strip with silver nanoparticles colored red, orange, and green linked to antibodies associated with Ebola, yellow fever, and dengue fever respectively. A blood sample flowing through the paper strip comes in contact with the nanoparticles that react and change color if the targeted viral protein is present. The test takes about 10 minutes.

“When we run a patient sample through the strip, if you see an orange band you know they have yellow fever, if it shows up as a red band you know they have Ebola, and if it shows up green then we know that they have dengue,” notes Hamad-Schifferli.

The team is testing the device in the lab with synthetic viral proteins, as well as blood serum samples from infected animals. Their hope is to gain approval from the U.S. Food and Drug Administration to use the device in areas where the Ebola outbreak, while diminished overall, continues.

The researchers also believe the technology can be adapted to other infectious diseases. “There will undoubtedly be other viral outbreaks,” notes Gehrke. “It might be Sudan virus, it might be another hemorrhagic fever. What we’re trying to do is develop the antibodies needed to be ready for the next outbreak that’s going to happen.”

Read more:

• Biotech Licenses Cell Research for Ebola Treatments
• Project Aims to Boost Ebola Drug Production
• Ebola-Marburg Vaccine Development, Testing Contract Awarded
• FDA Exemption Sought for Ebola Blood Plasma Device
• Drug Screening Target Designed for All Ebola Types

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