Effects of optical attenuation, heat diffusion, and acoustic coherence in photoacoustic signals produced by nanoparticles

Alba-Rosales, J. E.; Ramos‐Ortíz, Gabriel; Escamilla-Herrera, L. F.; Reyes-Ramírez, B.; Polo‐Parada, Luis; Gutiérrez-Juárez, G.

doi:10.1063/1.5008873

Cited by 6 publications

(6 citation statements)

References 41 publications

(73 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This will be investigated in the next section. The velocity potential equation, (22), is solved for each medium with appropriate initial and boundary conditions. Zero velocity and acceleration are used for initial conditions, yielding zero velocity potential and its derivative at time t ¼ 0, i. e.,…”

Section: Resultsmentioning

confidence: 99%

“…Analogous to the temperature solution, the solution of the velocity potential equation with the initial and boundary conditions, Eqs. (22) and (25d), is sought by first writing the equations in a dimensionless form using a change of variable to a dimensionless velocity potential as…”

Section: Resultsmentioning

confidence: 99%

“…In addition to a single nanosphere, we also present estimates of the PA pressure signals arising from an aggregation of nanospheres in a suspension. For an aggregates of nanospheres, the PA signal can be estimated as superposition of the PAs from individual nanospheres, provided the optical and heating behaviors of nanospheres remain unchanged as they are brought together 21,22 .…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Photoacoustics of core–shell nanospheres using comprehensive modeling and analytical solution approach

et al. 2019

View full text Add to dashboard Cite

Photoacoustic visualization of nanoparticles is capable of high contrast imaging at depth greater than that of traditional optical imaging techniques. Identifying the impact of various parameters on the photoacoustic signal is crucial in the design of effective medical imaging and diagnostics. Here, we develop a complete model of Fourier heat conduction incorporating the interfacial thermal resistance and photoacoustic equation for core-shell nanospheres in a fluid under nanosecond pulsed laser illumination. An analytical solution is obtained, elucidating the contribution of each region (core, shell, or the fluid) in the generation of the photoacoustic signal. The model reveals that the sharper the laser pulse temporal waveform is, the higher the sensitivity of the generated photoacoustic signal will be to the interfacial thermal resistance, and, thus, the higher the possibility of photoacoustic signal amplification will be using silica-coating. The comprehensive model and adopted analytical solution reveal the underlying physics of the photoacoustic signal generation form core-shell nanosphere systems.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Photoacoustics of core–shell nanospheres using comprehensive modeling and analytical solution approach

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The above-described approaches are valid until non-linearities arise in the laser / PNP interaction, thereby influencing the photoacoustic signal [ 61 ]. This possibility has been described both theoretically [ 65 , 66 ] and experimentally [ 58 , 60 , [67] , [68] , [69] ]. Several adjustable experimental conditions determine signal non-linearities, including the laser pulse characteristics and PNP concentration.…”

Section: Photoacoustic Response Of Nanomaterialsmentioning

confidence: 99%

Optothermal properties of plasmonic inorganic nanoparticles for photoacoustic applications

Gellini

Feis

2021

Photoacoustics

View full text Add to dashboard Cite

Plasmonic systems are becoming a favourable alternative to dye molecules in the generation of photoacoustic signals for spectroscopy and imaging. In particular, inorganic nanoparticles are appealing because of their versatility. In fact, as the shape, size and chemical composition of nanoparticles are directly correlated with their plasmonic properties, the excitation wavelength can be tuned to their plasmon resonance by adjusting such traits. This feature enables an extensive spectral range to be covered. In addition, surface chemical modifications can be performed to provide the nanoparticles with designed functionalities, e.g., selective affinity for specific macromolecules. The efficiency of the conversion of absorbed photon energy into heat, which is the physical basis of the photoacoustic signal, can be accurately determined by photoacoustic methods. This review contrasts studies that evaluate photoconversion in various kinds of nanomaterials by different methods, with the objective of facilitating the researchers' choice of suitable plasmonic nanoparticles for photoacoustic applications.

show abstract

“…Comprehensive theoretical studies on photoacoustic generation have been reported in the literature . And recent theoretical studies can be found elsewhere …”

Section: Photoacoustic Generation—mechanism and General Considerationsmentioning

confidence: 99%

Efficient Photoacoustic Conversion in Optical Nanomaterials and Composites

Lee

Baac

et al. 2018

Advanced Optical Materials

View full text Add to dashboard Cite

approaches. While addressing the limitations of the electrical counterparts (e.g., massive amounts of radio frequency (RF) cabling and electromagnetic (EM) interference), a photoacoustic approach for gene rat ing high-amplitude ultrasound has created new opportunities.Active research on efficient photo acoustic materials has started with the development of photoacoustic contrast mediums (e.g., exogenous contrast particles) for contrast enhancement. [3][4][5] Recent advances in nanofabrication technologies have allowed to develop more efficient photoacoustic contrast mediums, [3] such as metal nanoparticles having enhanced optical absorption due to optical resonance. Later, by coating such nanoparticles on a flat substrate, layered structures were developed for generating high-amplitude ultrasound. Among many nanoparticles, gold nanoparticles were widely used owing to strong resonance. [6] In fact, these initial efforts to increase photoacoustic conversion were focused on increasing light absorption, while the critical role of thermal expansion for photoacoustic generation were often overlooked.To enhance thermal expansion for photoacoustic generation, researchers have started to fabricate composite materials, composed of light-absorbing materials mixed with polymers with high thermal expansion coefficients. These polymer-based composites significantly enhance photoacoustic conversion efficiency. Among many polymers, polydimethylsiloxane (PDMS) is exclusively used because of its high thermal expansion, optical transparency, and acoustic impedance comparable to that of water. [7][8][9][10][11] Photoacoustic pulses generated with PDMSbased composites have the characteristics of high amplitude and high frequency, which have enabled interesting applications such as cavitation-based therapy [12] and imaging. [13] For photoacoustic composites, there are a myriad of light-absorbing nanomaterials such as metal absorbers [6] and carbon nanomaterials (e.g., carbon black (CB), [14] carbon nanotube (CNT), [7,10] carbon nanofiber (CNF), [9] candle soot (CS), [8] and reduced graphene oxide (rGO) [15] ). These light-absorbing materials of nanometer sizes have an advantage over microscale absorbing materials [7] in facilitating heat transfer from the light absorbers into the surrounding mediums. Such facilitated heat transfer is another key factor that contributes to photoacoustic energy conversion.In this Review, we will start with general considerations of photoacoustic generation in nanomaterial composites. Various photoacoustic composites enabling interesting applications will be introduced. In addition, recent efforts will be reviewed from an application perspective. Also, we will discuss outlook and future directions.Photoacoustic pulses generated by pulsed laser irradiation have the characteristics of high frequency and wide bandwidth, which are desirable for imaging and sensing. Efficient photoacoustic composites have been developed for fabricating photoacoustic transmitters capable of generating highamplitude ultrasound....

show abstract

Effects of optical attenuation, heat diffusion, and acoustic coherence in photoacoustic signals produced by nanoparticles

Cited by 6 publications

References 41 publications

Photoacoustics of core–shell nanospheres using comprehensive modeling and analytical solution approach

Photoacoustics of core–shell nanospheres using comprehensive modeling and analytical solution approach

Optothermal properties of plasmonic inorganic nanoparticles for photoacoustic applications

Efficient Photoacoustic Conversion in Optical Nanomaterials and Composites

Contact Info

Product

Resources

About