UNDERSTANDING THE
PHYSICS OF A NEW TYPE
OF PHOTONIC BIOSENSOR
A whispering gallery mode (WGM) resonator is a miniature optical device that recirculates light. A biosensor can be made by functionalizing a WGM device and
looking for small changes in its resonance wavelengths due to binding events of
chemicals and biological agents. However, the device’s effectiveness is hampered
by its inability to detect very small concentrations of analytes.
ECE Associate Professor Lynford Goddard and his students have conducted
simulations to explain the fundamental physics of a new type of WGM biosensor that incorporates gold nanoparticles around the circumference of the WGM
waveguide. The nanoparticles form a plasmonic chain ring resonator (PCRR), a
structure that experiences a collective oscillation in the presence of light.
The integrated WGM-PCRR biosensor creates a wavelength shift that is a few orders of magnitude larger than the conventional WGM biosensor because of the
way that light is localized in the PCRR for specific sizes and spacings of nanoparticles. The enhanced sensitivity should enable the detection of a single binding
event of a small protein such as a Thyroglobulin cancer marker protein.
FACULTY AWARDS
MNTL FACULTY AFFILIATES ELECTED
TO NATIONAL ACADEMY OF SCIENCES
Chemistry Professor Catherine Murphy and Materials Science & Engineering Professor
John Rogers were elected to the National Academy of Sciences in 2015. Murphy, who
is associate director of the Frederick Seitz Materials Research Lab (MRL) on campus,
works to develop inorganic nanomaterials for applications in biology and technology.
Her group develops methods to manufacture tiny nanorods made of metals such as
gold, silver and copper, and she investigates their uses for imaging cells, chemical sensing and photothermal therapy. She also studies the environmental impact of nanoparticles and how their properties influence their behavior.
Rogers, who is the director of the Frederick Seitz MRL, is a pioneer of flexible, stretchable and transient electronics. He combines soft, stretchable materials with microscale
and nanoscale electronic components to create classes of devices with a wide range of
practical applications from medicine to sensing to solar energy.
MNTL FACULTY RESEARCHER ELECTED TO NAE
ECE Professor J. Gary Eden was elected to the National Academy of Engineering, one
of the highest professional honors an engineer can receive. Eden, who uses lasers to
study how visible and ultraviolet light interact with matter, was honored for development
and commercialization of micro-plasma technologies and excimer lasers. His work has
led to advances in multiple areas of application. For example, excimer lasers, a class of
ultraviolet lasers Eden developed, are used industrially in semiconductor manufacturing and clinically for eye surgeries. His work also has advanced such areas as ultrafast
spectroscopy, which uses laser pulses to study the interactions between atoms and molecules, and photochemical vapor deposition, which uses lasers to deposit thin films of
semiconductors and other materials on a surface.
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