BU’s Photonics Center was chosen by the National Science Foundation earlier this year to set up an industry-university cooperative research center called the Center for Biopohotonic Sensors and Systems (CBSS). CBSS is a partnership between BU’s Photonics Center and the Center for Biophotonics Science and Technology at UC Davis. CBSS is tasked with developing portable, inexpensive tools that advance personalized medicine while lowering healthcare costs. The center fosters an environment of collaboration where industry and university researchers can exchange ideas and foster high quality fundamental research that is relevant to industry. Industry representatives come from a wide array of companies developing diagnostic, analytical, and monitoring devices used in the clinical setting and provide direct input into the direction of research at the center.
Two biosensor technologies being developed at CBSS aim to deliver on the promise of low cost, personalized medicine. The Interferometric Reflectance Imaging Sensor (called IRIS) was developed by Selim Ünlü (Professor of Electrical and Computer Engineering) and his group, in collaboration with Bennett Goldberg (Professor, Physics) and MITRE Corp. IRIS is a highly sensitive device that can identify single viral particles, as well as other pathogens and even antibodies, bound on the surface of a silicon dioxide-coated microarray. IRIS detects these particles in an accurate, fast, label-free, and low-cost manner. The device’s multi-wavelength LEDs serially probe bound nanoparticles on the microarray surface. The presence of bound nanoparticles “interferes” with the reflectance of light from the surface. The device detects this change in light reflectance, which is used to calculate particle size. IRIS has a small footprint (think shoe box), and is battery operated. IRIS can count and estimate the size of up to one million nanoparticles bound to the surface of a single microarray chip. To date, IRIS has detected the vesicular stomatitis virus (VSV) and H1N1, and can distinguish between immunoglobulins IgG and IgE. Immunoglobulin detection with IRIS could be developed into a highly specific point-of-care diagnostic test of the specific molecules causing allergies in a patient.
Hatice Altug (Assistant Professor of Electrical & Computer Engineering) and researchers in her lab have discovered a high-throughput, low-cost method of producing ultra-smooth surfaces on microarray chips that exhibit exquisite optical properties. The ultra-smooth surfaces allow the investigators to exploit surface plasmon resonances (SPR), in which light waves propagate parallel to the metal-dielectric interface. Nanohole arrays are arranged in multiple square patterns of 90 microns x 90 microns each on the smooth microarray surface. Specific binding agents on the microarray surface extract viruses or antibodies from solution. When these large biomolecules are bound, the plasmon resonance of a particular square nanohole array is extinguished. Surprisingly, the binding of specific viruses or antibodies onto a square nanohole array can be directly visualized with the naked eye, without the assistance of cameras or other devices. Altug’s biosensor is able to rapidly detect live viruses from biological samples with minimal sample prep. Collaborating with John Connor, the group was the first to detect live viruses (VSV in this case) using plasmonic nanohole arrays. She was recently awarded a 5-year, $5M grant to develop a prototype that is ready for clinical testing. This technology can be used as an ultrasensitive, low cost, and label-free point-of-care diagnostic for biodefense, airport security, and in resource-limited settings.
For more information about the Center for Biophotonic Sensors & Systems, please visit: http://www.bu.edu/cbss/
