"Plasmonic interferometric sensor arrays for high-performance
label-free biomolecular detection" that has been featured as a
cover article of the journal Lab on a Chip.
In this work, Professor Gan and co-authors demonstrate a
plasmonic interferometric biosensor that consists of arrays of
circular aperture–groove nanostructures patterned on a gold
film for phase-sensitive biomolecular detection. The phase and
amplitude of interfering surface plasmon polaritons (SPPs) in the
proposed device can be effectively engineered by structural tuning,
providing flexible and efficient control over the plasmon line
shape observed through SPP interference. Spectral fringes with high
contrast, narrow linewidth, and large amplitude have been
experimentally measured and permit the sensitive detection of
protein surface coverage as low as 0.4 pg mm. This sensor
resolution compares favorably with commercial prism-based surface
plasmon resonance systems (0.1 pg mm) but is achieved here using a
significantly simpler collinear transmission geometry, a
miniaturized sensor footprint, and a low-cost compact spectrometer.
Furthermore, superior sensor performance is demonstrated
using the intensity interrogation method, which can be combined
with CCD imaging to upscale our platform to high-throughput array
sensing. A novel low-background interferometric sensing scheme
yields a high sensing figure of merit (FOM*) of 146 in the visible
region, surpassing that of previous plasmonic biosensors and
facilitating ultrasensitive high-throughput detection.
More details can be found at:
"Plasmonic interferometric sensor arrays for high-performance label-free biomolecular detection"