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based test for Zika virus.
Purple dots indicate samples
infected with Zika, and yellow
dots indicate Zika-free samples.
Photo courtesy of the Wyss
Institute at Harvard University
A new paper-based test can diagnose Zika virus infection within a few hours, according to research published in Cell.
The test is based on technology previously developed to detect the Ebola virus.
In October 2014, researchers demonstrated that they could create synthetic gene networks and embed them on small discs of paper.
These gene networks can be programmed to detect a particular genetic sequence, which causes the paper to change color.
Upon learning about the Zika outbreak, the researchers decided to try adapting this technology to diagnose Zika.
“In a small number of weeks, we developed and validated a relatively rapid, inexpensive Zika diagnostic platform,” said study author James Collins, PhD, of the Massachusetts Institute of Technology in Cambridge.
Dr Collins and his colleagues developed sensors, embedded in the paper discs, that can detect 24 different RNA sequences found in the Zika viral genome. When the target RNA sequence is present, it initiates a series of interactions that turns the paper from yellow to purple.
This color change can be seen with the naked eye, but the researchers also developed an electronic reader that makes it easier to quantify the change, especially in cases where the sensor is detecting more than one RNA sequence.
All of the cellular components necessary for this process—including proteins, nucleic acids, and ribosomes—can be extracted from living cells and freeze-dried onto paper.
These paper discs can be stored at room temperature, making it easy to ship them to any location. Once rehydrated, all of the components function just as they would inside a living cell.
The researchers also incorporated a step that boosts the amount of viral RNA in the blood sample before exposing it to the sensor, using a system called nucleic acid sequence based amplification (NASBA). This amplification step, which takes 1 to 2 hours, increases the test’s sensitivity 1 million-fold.
The team tested this diagnostic platform using synthesized RNA sequences corresponding to the Zika genome, which were then added to human blood serum.
They found the test could detect very low viral RNA concentrations in those samples and could also distinguish Zika from dengue.
The researchers then tested samples taken from monkeys infected with the Zika virus. (Samples from humans affected by the current Zika outbreak were too difficult to obtain.)
The team found that, in these samples, the test could detect viral RNA concentrations as low as 2 or 3 parts per quadrillion.
The researchers believe this approach could also be adapted to other viruses that may emerge in the future. Dr Collins hopes to team up with other scientists to further develop the technology for diagnosing Zika.
“Here, we’ve done a nice proof-of-principle demonstration, but more work and additional testing would be needed to ensure safety and efficacy before actual deployment,” he said. “We’re not far off.” 
based test for Zika virus.
Purple dots indicate samples
infected with Zika, and yellow
dots indicate Zika-free samples.
Photo courtesy of the Wyss
Institute at Harvard University
A new paper-based test can diagnose Zika virus infection within a few hours, according to research published in Cell.
The test is based on technology previously developed to detect the Ebola virus.
In October 2014, researchers demonstrated that they could create synthetic gene networks and embed them on small discs of paper.
These gene networks can be programmed to detect a particular genetic sequence, which causes the paper to change color.
Upon learning about the Zika outbreak, the researchers decided to try adapting this technology to diagnose Zika.
“In a small number of weeks, we developed and validated a relatively rapid, inexpensive Zika diagnostic platform,” said study author James Collins, PhD, of the Massachusetts Institute of Technology in Cambridge.
Dr Collins and his colleagues developed sensors, embedded in the paper discs, that can detect 24 different RNA sequences found in the Zika viral genome. When the target RNA sequence is present, it initiates a series of interactions that turns the paper from yellow to purple.
This color change can be seen with the naked eye, but the researchers also developed an electronic reader that makes it easier to quantify the change, especially in cases where the sensor is detecting more than one RNA sequence.
All of the cellular components necessary for this process—including proteins, nucleic acids, and ribosomes—can be extracted from living cells and freeze-dried onto paper.
These paper discs can be stored at room temperature, making it easy to ship them to any location. Once rehydrated, all of the components function just as they would inside a living cell.
The researchers also incorporated a step that boosts the amount of viral RNA in the blood sample before exposing it to the sensor, using a system called nucleic acid sequence based amplification (NASBA). This amplification step, which takes 1 to 2 hours, increases the test’s sensitivity 1 million-fold.
The team tested this diagnostic platform using synthesized RNA sequences corresponding to the Zika genome, which were then added to human blood serum.
They found the test could detect very low viral RNA concentrations in those samples and could also distinguish Zika from dengue.
The researchers then tested samples taken from monkeys infected with the Zika virus. (Samples from humans affected by the current Zika outbreak were too difficult to obtain.)
The team found that, in these samples, the test could detect viral RNA concentrations as low as 2 or 3 parts per quadrillion.
The researchers believe this approach could also be adapted to other viruses that may emerge in the future. Dr Collins hopes to team up with other scientists to further develop the technology for diagnosing Zika.
“Here, we’ve done a nice proof-of-principle demonstration, but more work and additional testing would be needed to ensure safety and efficacy before actual deployment,” he said. “We’re not far off.”
based test for Zika virus.
Purple dots indicate samples
infected with Zika, and yellow
dots indicate Zika-free samples.
Photo courtesy of the Wyss
Institute at Harvard University
A new paper-based test can diagnose Zika virus infection within a few hours, according to research published in Cell.
The test is based on technology previously developed to detect the Ebola virus.
In October 2014, researchers demonstrated that they could create synthetic gene networks and embed them on small discs of paper.
These gene networks can be programmed to detect a particular genetic sequence, which causes the paper to change color.
Upon learning about the Zika outbreak, the researchers decided to try adapting this technology to diagnose Zika.
“In a small number of weeks, we developed and validated a relatively rapid, inexpensive Zika diagnostic platform,” said study author James Collins, PhD, of the Massachusetts Institute of Technology in Cambridge.
Dr Collins and his colleagues developed sensors, embedded in the paper discs, that can detect 24 different RNA sequences found in the Zika viral genome. When the target RNA sequence is present, it initiates a series of interactions that turns the paper from yellow to purple.
This color change can be seen with the naked eye, but the researchers also developed an electronic reader that makes it easier to quantify the change, especially in cases where the sensor is detecting more than one RNA sequence.
All of the cellular components necessary for this process—including proteins, nucleic acids, and ribosomes—can be extracted from living cells and freeze-dried onto paper.
These paper discs can be stored at room temperature, making it easy to ship them to any location. Once rehydrated, all of the components function just as they would inside a living cell.
The researchers also incorporated a step that boosts the amount of viral RNA in the blood sample before exposing it to the sensor, using a system called nucleic acid sequence based amplification (NASBA). This amplification step, which takes 1 to 2 hours, increases the test’s sensitivity 1 million-fold.
The team tested this diagnostic platform using synthesized RNA sequences corresponding to the Zika genome, which were then added to human blood serum.
They found the test could detect very low viral RNA concentrations in those samples and could also distinguish Zika from dengue.
The researchers then tested samples taken from monkeys infected with the Zika virus. (Samples from humans affected by the current Zika outbreak were too difficult to obtain.)
The team found that, in these samples, the test could detect viral RNA concentrations as low as 2 or 3 parts per quadrillion.
The researchers believe this approach could also be adapted to other viruses that may emerge in the future. Dr Collins hopes to team up with other scientists to further develop the technology for diagnosing Zika.
“Here, we’ve done a nice proof-of-principle demonstration, but more work and additional testing would be needed to ensure safety and efficacy before actual deployment,” he said. “We’re not far off.”