185. NANOPARTICLE-POLYMER-NANOFIBER OPTICAL PROBE FOR BIOLOGICAL MECHANICAL MEASUREMENTS
Name: Qian Huang
Grad Year: 2016
Plasmonic nanoparticles embedded in the evanescent field of a nanofiber waveguide have scattering cross-sections that are extremely sensitive (~ 1Å) to distance changes normal to the propagation direction of light. This enhanced distance sensitivity is due to the strong plasmon-dielectric coupling effects near the fiber-nanoparticle interface coupled with the sharp decaying near-field of the waveguide. Here we demonstrate a new breed of ultrasensitive, single element force transducers that leverage thin compressible fiber claddings linked to plasmonic nanoparticles to provide mechanical feedback. The distance and force sensitivity of the probes are calibrated using a combined optical-AFM instrument equipped with tips that we controllably functionalize with single nanoparticles. The experiments demonstrate that sub-pN force responses can be attained from the probes and tuned based upon the mechanical properties of the cladding. The probes are also independently used to study the nanomechanical behavior of various systems including bacteria behavior in solution and cardiomyocyte mechanics in real time. Compared to other force transducers including optical traps and AFMs, our system is substantially more compact, can be easily multiplexed to allow a large number of force recordings to occur along a single fiber, and allows for straightforward embedded as well as intracellular measurements.
Industry Application Area(s)
Electronics/Photonics | Life Sciences/Medical Devices & Instruments | Materials