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Updated: Jul 5, 2026

Synthesis and Operation of Fluorescent-core Microcavities for Refractometric Sensing
Published on: March 13, 2013
Hybrid microgels photoresponsive in the near-infrared spectral range
Ivan Gorelikov1, Lora M Field, Eugenia Kumacheva
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M6S 3H6, Canada.
Abstract:
We report for the first time a photothermally responsive composite material based on polymer microgel particles doped with gold nanorods. We used the dependence of the longitudinal surface plasmon of the gold nanorods on their aspect ratio to synthesize nanoparticles with strong absorption in the near-IR spectral range (in the "water window"). The nanoparticles were incorporated in the interior of temperature-responsive poly(N-isopropylacrylamide-acrylic acid) microgels. Upon irradiation at lambda = 810 nm, hybrid microgel particles doped with Au nanorods underwent a strong deswelling phase transition. These photothermally responsive microgels can be used to carry and release small molecules (e.g., small protein molecules and drugs).
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