Portable Biosensor Quickly Detects Dangerous Viruses

A simple diagnostic tool has been developed that can quickly identify dangerous viruses such as Ebolavirus and Marburgvirus. The small biosensor, which can detect viruses in a blood sample, could be used in developing nations, airports, and other places where natural or manmade outbreaks could erupt.

The biosensor detects intact viruses by exploiting plasmonic nanohole arrays, or arrays of apertures with diameters of about 200 nm to 350 nm on metallic films that transmit light more strongly at certain wavelengths. When a live virus in a sample solution, such as blood or serum, binds to the sensor surface, the refractive index in the close vicinity of the sensor changes, causing a detectable shift in the resonance frequency of the light transmitted through the nanoholes. The magnitude of that shift reveals the presence and concentration of the virus in the solution.

Traditional virus diagnostic tools such as enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) remain strong diagnostic options, but they require significant infrastructure and sample preparation time. A team of scientists from Boston University (Boston, MA, USA) introduced the novel biosensor that directly detects live viruses from biological media with little to no sample preparation.

Working in collaboration with the US Army Medical Research Institute for Infectious Diseases USAMRIID; Frederick, MD, USA), the team demonstrated reliable detection of hemorrhagic fever virus surrogates (i.e., for the Ebolavirus) and poxviruses (such as monkeypox or smallpox) in ordinary biological laboratory settings.

The new device is described in the November 5, 2010 online version of Nano Letters.

"By enabling ultraportable and fast detection, our technology can directly impact the course of our reaction against bioterrorism threats and dramatically improve our capability to confine viral outbreaks," said Assistant Prof. Hatice Altug of the Boston University College of Engineering, who co-led the team with Assistant Prof. John Connor of the Boston University School of Medicine.

The scientists are now working on highly portable version of the biosensor platform using microfluidic technology designed for use in the field with minimal human interference. They plan to subject the platform to initial tests on samples containing Ebolavirus, Marburgvirus, and other hemorrhagic fever viruses in the United States, followed by additional tests in resource-limited countries in Africa where outbreaks of hemorrhagic fever occur.

Related Links:
US Army Medical Research Institute for Infectious Diseases
Boston University
Boston University College of Engineering
Boston University School of Medicine