A new biochip – appropriately named SMART – can reliably and speedily detect the flu virus, can be carried in a first aid kit and can used as easily as an iPhone. The biochip, designed by Brown University researchers, zeroes in on the infected RNA sequence and separates it from the larger strand with the help of tiny magnets. SMART stands for “A Simple Method for Amplifying RNA Targets”. Physically, it is essentially a series of tubes with bulbs on the ends of each, etched like channels into the biochip, the Journal of Molecular Diagnostics reports. There are other pathogen-diagnostic detectors, notably the Polymerase Chain Reaction device (which targets DNA) and the Nucleic Acid Sequence Based Amplification (which also targets RNA), according to a Brown statement.
The SMART detector is unique in that the engineers use a DNA probe with base letters that match the code in the targeted sequence. This ensures the probe will latch on only to the specific RNA strand being assayed. The team inundates the sample with probes, to ensure that all RNA molecules bind to a probe. ”We wanted to make something simple. It’s a low-cost device for active, on-site detection, whether it’s influenza, HIV, or TB (tuberculosis),” said Anubhav Tripathi, study co-author at Brown.
“The device allows us to design probes that are both sensitive and specific,” said Tripathi, associate professor of engineering at Brown. Stephanie McCalla, who earned her doctorate at Brown last year and is now at the California Institute of Technology, led the study. In April 2009, the world took notice as reports surfaced of a virus in Mexico that had mutated from pigs and was being passed from human to human. The H1N1 “swine flu,” as the virus was named, killed more than 18,000 people globally, according to the World Health Organization.
The Centres for Disease Control and Prevention, US, said it was the first global pandemic in more than four decades. Swine flu will not be the last viral mutation to cause a worldwide stir. One way to contain the next outbreak is by administering tests at the infection’s source, pinpointing and tracking the pathogen’s spread in real time. But such efforts have been stymied by devices that are costly, unwieldy and unreliable, until the development of the Brown device.