Microbubble Resonators for All-Optical Photoacoustics of Flowing Contrast Agents

Sensors

Silvia Soria¹  Sonia Centi¹  Fulvio Ratto¹  Lucia Cavigli¹  Gabriele Frigenti²  Gualtiero Nunzi Conti²  Alberto Fernández-Bienes³  Tupak García-Fernández⁴ 

[1] CNR-IFAC, Istituto di Fisica Applicata “Nello Carrara”, Consiglio Nazionale delle Ricerche, via Madonna del Piano 10, I50019 Sesto Fiorentino (FI), Italy;Centro Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Compendio del Viminale, Piazza del Viminale 1, 00184 Rome, Italy;Facultad de Ingeniería, Universidad Nacional Autónoma de México (UNAM), Ciudad de México C.P. 04510, Mexico;Universidad Autónoma de la Ciudad de México (UACM), Prolongación San Isidro 151, Col. San Lorenzo Tezonco, México D.F. C.P. 09790, Mexico;

关键词: photoacoustics;    whispering gallery mode resonators;    microbubble resonators;    microfluidics;    characterization of nanoparticles;    flow cytometry;   

DOI  :  10.3390/s20061696

来源: DOAJ

【 摘 要 】

In this paper, we implement a Whispering Gallery mode microbubble resonator (MBR) as an optical transducer to detect the photoacoustic (PA) signal generated by plasmonic nanoparticles. We simulate a flow cytometry experiment by letting the nanoparticles run through the MBR during measurements and we estimate PA intensity by a Fourier analysis of the read-out signal. This method exploits the peaks associated with the MBR mechanical eigenmodes, allowing the PA response of the nanoparticles to be decoupled from the noise associated with the particle flow whilst also increasing the signal-to-noise ratio. The photostability curve of a known contrast agent is correctly reconstructed, validating the proposed analysis and proving quantitative PA detection. The experiment was run to demonstrate the feasible implementation of the MBR system in a flow cytometry application (e.g., the detection of venous thrombi or circulating tumor cells), particularly regarding wearable appliances. Indeed, these devices could also benefit from other MBR features, such as the extreme compactness, the direct implementation in a microfluidic circuit, and the absence of impedance-matching material.

【 授权许可】

Unknown