Open AccessMicrobubble resonators for scattering-free absorption spectroscopy of nanoparticles
Author(s) -
Gabriele Frigenti,
Lucia Cavigli,
Fulvio Ratto,
Sonia Centi,
Т. В. Мурзина,
Daniele Farnesi,
S. Pelli,
Silvia Soria,
G. Nunzi Conti
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.434868
Subject(s) - materials science , resonator , optics , absorbance , photothermal therapy , light scattering , scattering , nanorod , absorption (acoustics) , spectroscopy , plasmon , microfluidics , absorption spectroscopy , optoelectronics , nanoparticle , lab on a chip , nanotechnology , physics , quantum mechanics , composite material
We present a proof-of-concept experiment where the absorbance spectra of suspensions of plasmonic nanoparticles are accurately reconstructed through the photothermal conversion that they mediate in a microbubble resonator. This thermal detection produces spectra that are insensitive towards light scattering in the sample, as proved experimentally by comparing the spectra of acqueos gold nanorods suspensions in the presence or absence of milk powder. In addition, the microbubble system allows for the interrogation of small samples (below 40 nl) while using a low-intensity beam (around 20 µW) for their excitation. In perspective, this system could be implemented for the characterization of turbid biological fluids through their optical absorption, especially when considering that the microbubble resonator naturally interfaces to a microfluidic circuit and may easily fit within portable or on-chip devices.