Ultraefficient thermoacoustic conversion through a split ring resonator

Abstract. Microwaves, which have a ∼10-cm wavelength, can penetrate deeper into tissue than photons, heralding exciting deep tissue applications such as modulation or imaging via the thermoacoustic effect. Thermoacoustic conversion efficiency is however very low, even with an exogenous contrast agent. We break this low-conversion limit, using a split ring resonator to effectively collect and confine the microwaves into a submillimeter hot spot for ultrasound emission and achieve a conversion efficiency over 2000 times higher than other reported thermoacoustic contrast agents. Importantly, the frequency of emitted ultrasound can be precisely tuned and multiplexed by modulation of the microwave pulses. Such performance is inaccessible by a piezoelectric-based transducer or a photoacoustic emitter and, therefore, split ring resonators open up new opportunities to study the frequency response of cells in ultrasonic biomodulation. For applications in deep tissue localization, a split ring resonator can be used as a wireless, battery-free ultrasound beacon placed under a breast phantom.

[1]  M Halliwell,et al.  Sonoporation, drug delivery, and gene therapy , 2010, Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine.

[2]  Zongfu Yu,et al.  Large single-molecule fluorescence enhancements produced by a bowtie nanoantenna , 2009 .

[3]  Mikhail G. Shapiro,et al.  Infrared light excites cells by changing their electrical capacitance , 2012, Nature Communications.

[4]  J. Pendry,et al.  Magnetism from conductors and enhanced nonlinear phenomena , 1999 .

[5]  Yusuf Tufail,et al.  Ultrasonic neuromodulation by brain stimulation with transcranial ultrasound , 2011, Nature Protocols.

[6]  William J Tyler,et al.  Ultrasonic modulation of neural circuit activity , 2018, Current Opinion in Neurobiology.

[7]  Olivier J. F. Martin,et al.  Electromagnetic resonances in individual and coupled split-ring resonators , 2002 .

[8]  Lihong V. Wang,et al.  Microwave‐induced thermoacoustic tomography through an adult human skull , 2019, Medical physics.

[9]  Kaiming Liu,et al.  A fiber optoacoustic guide with augmented reality for precision breast-conserving surgery , 2018, Light: Science & Applications.

[10]  Wei Shi,et al.  Optical resolution photoacoustic microscopy using novel high-repetition-rate passively Q-switched microchip and fiber lasers. , 2010, Journal of biomedical optics.

[11]  M. Green,et al.  Surface plasmon enhanced silicon solar cells , 2007 .

[12]  Handong Sun,et al.  Advances and Prospects for Whispering Gallery Mode Microcavities , 2015 .

[13]  Pablo Bianucci,et al.  Linking plasma formation in grapes to microwave resonances of aqueous dimers , 2019, Proceedings of the National Academy of Sciences.

[14]  Federico Capasso,et al.  Plasmonic laser antenna , 2006 .

[15]  Lihong V. Wang,et al.  Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain , 2003, Nature Biotechnology.

[16]  Ekaterina Shamonina,et al.  Analytical formulation for the resonant frequency of split rings , 2009 .

[17]  Paul Beard,et al.  Exogenous contrast agents for thermoacoustic imaging: an investigation into the underlying sources of contrast. , 2014, Medical physics.

[18]  Da Xing,et al.  Thermoacoustic molecular tomography with magnetic nanoparticle contrast agents for targeted tumor detection. , 2010, Medical physics.

[19]  Lihong V. Wang,et al.  Photoacoustic imaging of biological tissue with intensity-modulated continuous-wave laser. , 2008, Journal of biomedical optics.

[20]  K. Saraswat,et al.  Nanometre-scale germanium photodetector enhanced by a near-infrared dipole antenna , 2008 .

[21]  Swen Kortig,et al.  Foundations For Microwave Engineering , 2016 .

[22]  Ji-Xin Cheng,et al.  Semiconducting Polymer Nanoparticles for Centimeters‐Deep Photoacoustic Imaging in the Second Near‐Infrared Window , 2017, Advanced materials.

[23]  W. Newsome,et al.  Effective parameters for ultrasound-induced in vivo neurostimulation. , 2013, Ultrasound in medicine & biology.

[24]  V. Ntziachristos,et al.  Precision assessment of label-free psoriasis biomarkers with ultra-broadband optoacoustic mesoscopy , 2017, Nature Biomedical Engineering.

[25]  S. Semenov.  Microwave tomography: review of the progress towards clinical applications , 2009, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[26]  Matthew D Langer,et al.  Design and evaluation of a wearable self-applied therapeutic ultrasound device for chronic myofascial pain. , 2013, Ultrasound in medicine & biology.

[27]  Zhong Ji,et al.  A review of microwave-induced thermoacoustic imaging: Excitation source, data acquisition system and biomedical applications , 2017 .

[28]  Paul C. Beard,et al.  Generating photoacoustic signals using high-peak power pulsed laser diodes , 2005, SPIE BiOS.

[29]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[30]  R. Shelby,et al.  Experimental Verification of a Negative Index of Refraction , 2001, Science.

[31]  Zhen Xu,et al.  Carbon-Nanotube Optoacoustic Lens for Focused Ultrasound Generation and High-Precision Targeted Therapy , 2012, Scientific Reports.

[32]  Hyeon Jeong Lee,et al.  Optoacoustic brain stimulation at submillimeter spatial precision , 2020, Nature Communications.

[33]  Hao Li,et al.  A transparent broadband ultrasonic detector based on an optical micro-ring resonator for photoacoustic microscopy , 2014, Scientific Reports.

[34]  S. Ourselin,et al.  Through-needle all-optical ultrasound imaging in vivo: a preclinical swine study , 2017, Light: Science & Applications.

[35]  Lihong V. Wang,et al.  Functional photoacoustic microscopy for high-resolution and noninvasive in vivo imaging , 2006, Nature Biotechnology.

[36]  Lukas Novotny,et al.  Near-field optical microscopy and spectroscopy with pointed probes. , 2006, Annual review of physical chemistry.

[37]  Lihong V. Wang,et al.  A practical guide to photoacoustic tomography in the life sciences , 2016, Nature Methods.

[38]  Manojit Pramanik,et al.  Single-walled carbon nanotubes as a multimodal-thermoacoustic and photoacoustic-contrast agent. , 2009, Journal of biomedical optics.