1
|
Sojahrood AJ, Li Q, Haghi H, Karshafian R, Porter TM, Kolios MC. Probing the pressure dependence of sound speed and attenuation in bubbly media: Experimental observations, a theoretical model and numerical calculations. ULTRASONICS SONOCHEMISTRY 2023; 95:106319. [PMID: 36931196 DOI: 10.1016/j.ultsonch.2023.106319] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/18/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
The problem of attenuation and sound speed of bubbly media has remained partially unsolved. Comprehensive data regarding pressure-dependent changes of the attenuation and sound speed of a bubbly medium are not available. Our theoretical understanding of the problem is limited to linear or semi-linear theoretical models, which are not accurate in the regime of large amplitude bubble oscillations. Here, by controlling the size of the lipid coated bubbles (mean diameter of ≈5.4μm), we report the first time observation and characterization of the simultaneous pressure dependence of sound speed and attenuation in bubbly water below, at and above microbubbles resonance (frequency range between 1-3 MHz). With increasing acoustic pressure (between 12.5-100 kPa), the frequency of the peak attenuation and sound speed decreases while maximum and minimum amplitudes of the sound speed increase. We propose a nonlinear model for the estimation of the pressure dependent sound speed and attenuation with good agreement with the experiments. The model calculations are validated by comparing with the linear and semi-linear models predictions. One of the major challenges of the previously developed models is the significant overestimation of the attenuation at the bubble resonance at higher void fractions (e.g. 0.005). We addressed this problem by incorporating bubble-bubble interactions and comparing the results to experiments. Influence of the bubble-bubble interactions increases with increasing pressure. Within the examined exposure parameters, we numerically show that, even for low void fractions (e.g. 5.1×10-6) with increasing pressure the sound speed may become 4 times higher than the sound speed in the non-bubbly medium.
Collapse
Affiliation(s)
- A J Sojahrood
- Department of Physics, Toronto Metropolitan University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada.
| | - Q Li
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - H Haghi
- Department of Physics, Toronto Metropolitan University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada
| | - R Karshafian
- Department of Physics, Toronto Metropolitan University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada
| | - T M Porter
- Department of Biomedical Engineering, Boston University, Boston, MA, USA; Department of Biomedical Engineering, University of Texas at Austin, Texas, USA
| | - M C Kolios
- Department of Physics, Toronto Metropolitan University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada.
| |
Collapse
|
2
|
Lin CW, Fan CH, Yeh CK. The Impact of Surface Drug Distribution on the Acoustic Behavior of DOX-Loaded Microbubbles. Pharmaceutics 2021; 13:pharmaceutics13122080. [PMID: 34959362 PMCID: PMC8703561 DOI: 10.3390/pharmaceutics13122080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/28/2021] [Accepted: 11/30/2021] [Indexed: 11/22/2022] Open
Abstract
Previous studies have reported substantial improvement of microbubble (MB)-mediated drug delivery with ultrasound when drugs are loaded onto the MB shell compared with a physical mixture. However, drug loading may affect shell properties that determine the acoustic responsiveness of MBs, producing unpredictable outcomes. The aim of this study is to reveal how the surface loaded drug (doxorubicin, DOX) affects the acoustic properties of MBs. A suitable formulation of MBs for DOX loading was first identified by regulating the proportion of two lipid materials (1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-distearoyl-sn-glycero-3-phospho-rac-glycerol sodium salt (DSPG)) with distinct electrostatic properties. We found that the DOX loading capacity of MBs was determined by the proportion of DSPG, since there was an electrostatic interaction with DOX. The DOX payload reduced the lipid fluidity of MBs, although this effect was dependent on the spatial uniformity of DOX on the MB shell surface. Loading DOX onto MBs enhanced acoustic stability 1.5-fold, decreased the resonance frequency from 12–14 MHz to 5–7 MHz, and reduced stable cavitation dose by 1.5-fold, but did not affect the stable cavitation threshold (300 kPa). Our study demonstrated that the DOX reduces lipid fluidity and decreases the elasticity of the MB shell, thereby influencing the acoustic properties of MBs.
Collapse
Affiliation(s)
- Chia-Wei Lin
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Ching-Hsiang Fan
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan;
- Medical Device Innovation Center, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan
| | - Chih-Kuang Yeh
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan;
- Correspondence:
| |
Collapse
|
3
|
Sridharan A, Hwang M, Kutty S, McCarville MB, Paltiel HJ, Piskunowicz M, Shellikeri S, Silvestro E, Taylor GA, Didier RA. Translational research in pediatric contrast-enhanced ultrasound. Pediatr Radiol 2021; 51:2425-2436. [PMID: 33991196 DOI: 10.1007/s00247-021-05095-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/21/2021] [Accepted: 04/28/2021] [Indexed: 10/21/2022]
Abstract
The role of contrast-enhanced ultrasound (CEUS) imaging is being widely explored by various groups for its use in the pediatric population. Clinical implementation of new diagnostic or therapeutic techniques requires extensive and meticulous preclinical testing and evaluation. The impact of CEUS will be determined in part by the extent to which studies are oriented specifically toward a pediatric population. Rather than simply applying principles and techniques used in the adult population, these studies are expected to advance and augment preexisting knowledge with pediatric-specific information. To further develop this imaging modality for use in children, pediatric-focused preclinical research is essential. In this paper we describe the development and implementation of the pediatric-specific preclinical animal and phantom models that are being used to evaluate CEUS with the goal of clinical translation to children.
Collapse
Affiliation(s)
- Anush Sridharan
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA.
| | - Misun Hwang
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Shelby Kutty
- Taussig Heart Center, Johns Hopkins University, Baltimore, MD, USA
| | - M Beth McCarville
- Department of Diagnostic Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Harriet J Paltiel
- Department of Radiology, Boston Children's Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | - Sphoorti Shellikeri
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - Elizabeth Silvestro
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
| | - George A Taylor
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Harvard Medical School, Boston, MA, USA
| | - Ryne A Didier
- Department of Radiology, Children's Hospital of Philadelphia, 3401 Civic Center Blvd., Philadelphia, PA, 19104, USA
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
4
|
Pellow C, Cherin E, Abenojar EC, Exner AA, Zheng G, Demore CEM, Goertz DE. High-Frequency Array-Based Nanobubble Nonlinear Imaging in a Phantom and In Vivo. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:2059-2074. [PMID: 33513102 PMCID: PMC8296974 DOI: 10.1109/tuffc.2021.3055141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
There has been growing interest in nanobubbles (NBs) for vascular and extravascular ultrasound contrast imaging and therapeutic applications. Studies to date have generally utilized low frequencies (<12 MHz), high concentrations (>109 mL-1), and uncalibrated B-mode or contrast-mode on commercial systems without reporting investigations on NB signatures upon which the imaging protocols should be based. We recently demonstrated that low concentrations (106 mL-1) of porphyrin-lipid-encapsulated NBs scatter nonlinearly at low (2.5, 8 MHz) and high (12.5, 25, 30 MHz) frequencies in a pressure threshold-dependent manner that is advantageous for amplitude modulation (AM) imaging. Here, we implement pressure-calibrated AM at high frequency on a commercial preclinical array system to enhance sensitivity to nonlinear scattering of three phospholipid-based NB formulations. With this approach, improvements in contrast to tissue ratio relative to B-mode between 12.4 and 22.8 dB are demonstrated in a tissue-mimicking phantom, and between 6.7 and 14.8 dB in vivo.
Collapse
|
5
|
Liu Y, Zhou Y, Xu J, Luo H, Zhu Y, Zeng X, Dong F, Wei Z, Yan F, Zheng H. Ultrasound molecular imaging-guided tumor gene therapy through dual-targeted cationic microbubbles. Biomater Sci 2021; 9:2454-2466. [PMID: 33594996 DOI: 10.1039/d0bm01857k] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The success of gene therapy depends largely on the development of gene vectors and effective gene delivery systems. It has been demonstrated that cationic microbubbles can be loaded with negatively charged plasmid DNA and thus improve gene transfection efficiency. In this study, we developed dual-targeting cationic microbubbles conjugated with iRGD peptides(Cyclo(Cys-Arg-Gly-Asp-Lys-Gly-Pro-Asp-Cys)) and CCR2 (chemokine (C-C motif) receptor 2) antibodies (MBiRGD/CCR2) for ultrasound molecular imaging and targeted tumor gene therapy. The ultrasound molecular imaging experiments showed that there were significantly enhanced ultrasound molecular imaging signals in the tumor that received MBiRGD/CCR2, compared with those that received MBiRGD, MBCCR2, or MBcontrol. As a therapy plasmid, pGPU6/GFP/Neo-shAKT2, carrying an expression cassette for the human AKT2 RNA interference sequence, was used. Our results demonstrated that MBiRGD/CCR2 had a significantly higher gene transfection efficiency than MBiRGD, MBCCR2, or MBcontrol under ultrasound irradiation, resulting in much lower AKT2 protein expression and stronger tumor growth inhibition effects in vivo and in vitro. In conclusion, our study demonstrated a novel gene delivery system via MBiRGD/CCR2 for ultrasound molecular-imaging-guided gene therapy of breast cancer.
Collapse
Affiliation(s)
- Yingying Liu
- Shenzhen Medical Ultrasound Engineering Center, Department of Ultrasonography, Shenzhen People's Hospital, Second Clinical Medical College of Jinan University, First Clinical Medical College of Southern University of Science and Technology, Shenzhen 518020, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Sojahrood AJ, Haghi H, Karshafian R, Kolios MC. Nonlinear dynamics and bifurcation structure of ultrasonically excited lipid coated microbubbles. ULTRASONICS SONOCHEMISTRY 2021; 72:105405. [PMID: 33360533 PMCID: PMC7803687 DOI: 10.1016/j.ultsonch.2020.105405] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 11/08/2020] [Accepted: 11/09/2020] [Indexed: 05/04/2023]
Abstract
In many applications, microbubbles (MBs) are encapsulated by a lipid coating to increase their stability. However, the complex behavior of the lipid coating including buckling and rupture sophisticates the dynamics of the MBs and as a result the dynamics of the lipid coated MBs (LCMBs) are not well understood. Here, we investigate the nonlinear behavior of the LCMBs by analyzing their bifurcation structure as a function of acoustic pressure. We show that, the LC can enhance the generation of period 2 (P2), P3, higher order subharmonics (SH), superharmonics and chaos at very low excitation pressures (e.g. 1 kPa). For LCMBs sonicated by their SH resonance frequency and in line with experimental observations with increasing pressure, P2 oscillations exhibit three stages: generation at low acoustic pressures, disappearance and re-generation. Within non-destructive oscillation regimes and by pressure amplitude increase, LCMBs can also exhibit two saddle node (SN) bifurcations resulting in possible abrupt enhancement of the scattered pressure. The first SN resembles the pressure dependent resonance phenomenon in uncoated MBs and the second SN resembles the pressure dependent SH resonance. Depending on the initial surface tension of the LCMBs, the nonlinear behavior may also be suppressed for a wide range of excitation pressures.
Collapse
Affiliation(s)
- A J Sojahrood
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Michael's Hospital, Toronto, Ontario, Canada.
| | - H Haghi
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Michael's Hospital, Toronto, Ontario, Canada
| | - R Karshafian
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Michael's Hospital, Toronto, Ontario, Canada
| | - M C Kolios
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Michael's Hospital, Toronto, Ontario, Canada
| |
Collapse
|
7
|
Chabouh G, Dollet B, Quilliet C, Coupier G. Spherical oscillations of encapsulated microbubbles: Effect of shell compressibility and anisotropy. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:1240. [PMID: 33639825 DOI: 10.1121/10.0003500] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
We introduce a model that describes spherical oscillations of encapsulated microbubbles in an unbounded surrounding fluid. A Rayleigh-Plesset-like equation is derived by coupling the Navier-Stokes equation that describes fluid dynamics with the Navier equation that describes solid dynamics via the internal/external boundary conditions. While previous models were restricted to incompressible isotropic shells, the solid shell is modeled here as a compressible viscoelastic isotropic material and then generalized to an anisotropic material. The exact value of the resonance frequency is calculated analytically, and the damping constant is computed in the approximation of weak damping. A correction of the widely used Church model for incompressible shells is evidenced, and the effects of shell compressibility and anisotropy are discussed.
Collapse
Affiliation(s)
- Georges Chabouh
- Université Grenoble Alpes, CNRS, LIPhy, F-38000 Grenoble, France
| | - Benjamin Dollet
- Université Grenoble Alpes, CNRS, LIPhy, F-38000 Grenoble, France
| | | | - Gwennou Coupier
- Université Grenoble Alpes, CNRS, LIPhy, F-38000 Grenoble, France
| |
Collapse
|
8
|
Pellow C, Tan J, Chérin E, Demore CEM, Zheng G, Goertz DE. High frequency ultrasound nonlinear scattering from porphyrin nanobubbles. ULTRASONICS 2021; 110:106245. [PMID: 32932144 DOI: 10.1016/j.ultras.2020.106245] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 08/14/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
Emerging contrast imaging studies have highlighted the potential of nanobubbles for both intravascular and extravascular applications. Reports to date on nanobubbles have generally utilized low frequencies (<12 MHz), high concentrations (>109 mL-1), and B-mode or contrast-mode on preclinical and clinical systems. However, none of these studies directly examined nanobubble acoustic signatures systematically to implement nonlinear imaging schemes in a methodical manner based on nanobubble behaviour. Here, nanobubble nonlinear behaviour is investigated at high frequencies (12.5, 25, 30 MHz) and low concentration (106 mL-1) in a channel phantom, with different pulse types in single- and multi-pulse sequences to examine behaviour under conditions relevant to high frequency imaging. Porphyrin nanobubbles are demonstrated to initiate nonlinear scattering at high frequencies in a pressure-threshold dependent manner, as previously observed at low frequencies. This threshold behaviour was then utilized to demonstrate enhanced nanobubble imaging with pulse inversion, amplitude modulation, and a combination of the two, progressing towards the improved sensitivity and expanded utility of these ultrasound contrast agents.
Collapse
Affiliation(s)
- Carly Pellow
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada; Princess Margaret Cancer Research Centre, 101 College St., Toronto, ON M5G 0A3, Canada; Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada.
| | - Josephine Tan
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada; Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Emmanuel Chérin
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Christine E M Demore
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada; Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Gang Zheng
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada; Princess Margaret Cancer Research Centre, 101 College St., Toronto, ON M5G 0A3, Canada
| | - David E Goertz
- Department of Medical Biophysics, University of Toronto, Toronto, ON M5G 1L7, Canada; Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| |
Collapse
|
9
|
Sojahrood AJ, Haghi H, Karshafian R, Kolios MC. Critical corrections to models of nonlinear power dissipation of ultrasonically excited bubbles. ULTRASONICS SONOCHEMISTRY 2020; 66:105089. [PMID: 32252009 DOI: 10.1016/j.ultsonch.2020.105089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 03/16/2020] [Accepted: 03/22/2020] [Indexed: 05/25/2023]
Abstract
Current models for calculating nonlinear power dissipation during the oscillations of acoustically excited bubbles generate non-physical values for the radiation damping (Drd) term for some frequency and pressure regions that include near resonance oscillations. Moreover, the ratio of the dissipated powers significantly deviate from the values that are calculated by the linear model at low amplitude oscillations (acoustic excitation pressure of PA=1 kPa and expansion ratio of <≊1.01). In high amplitude oscillation regimes (Pa⩾20 kPa), the dissipated power due to Drd deviates largely from the dissipated power as calculated by the widely accepted approach that uses the scattered power by the bubbles. We provide critical corrections to the present models. The validity of the results was examined in regimes of low amplitude oscillations and high amplitude oscillations. In the low amplitude regime, the ratio of the dissipated powers as calculated by the current and proposed model were compared with the linear model predictions. At higher amplitude oscillations, the dissipated power by radiation loss as calculated by the current and the proposed models were compared with the dissipated power calculated using the scattered power by the bubbles. We show that non-physical values are absent in the proposed model. Moreover, predictions of the proposed approach are identical to the predictions of the linear model and the dissipated power estimated using the scattered pressure by the bubble. We show that damping due to thermal effects, liquid viscosity and radiation heavily depend on the excitation pressure and that the linear model estimations are not valid even at pressures as low as 20 kPa.
Collapse
Affiliation(s)
- A J Sojahrood
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada.
| | - H Haghi
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada
| | - R Karshafian
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada
| | - M C Kolios
- Department of Physics, Ryerson University, Toronto, Canada; Institute for Biomedical Engineering, Science and Technology (IBEST) a partnership between Ryerson University and St. Mike's Hospital, Toronto, Ontario, Canada
| |
Collapse
|
10
|
Helfield B. A Review of Phospholipid Encapsulated Ultrasound Contrast Agent Microbubble Physics. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:282-300. [PMID: 30413335 DOI: 10.1016/j.ultrasmedbio.2018.09.020] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/11/2018] [Accepted: 09/20/2018] [Indexed: 06/08/2023]
Abstract
Ultrasound contrast agent microbubbles have expanded the utility of biomedical ultrasound from anatomic imaging to the assessment of microvascular blood flow characteristics and ultrasound-assisted therapeutic applications. Central to their effectiveness in these applications is their resonant and non-linear oscillation behaviour. This article reviews the salient physics of an oscillating microbubble in an ultrasound field, with particular emphasis on phospholipid-coated agents. Both the theoretical underpinnings of bubble vibration and the experimental evidence of non-linear encapsulated bubble dynamics and scattering are discussed and placed within the context of current and emerging applications.
Collapse
Affiliation(s)
- Brandon Helfield
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
| |
Collapse
|
11
|
Pellow C, Acconcia C, Zheng G, Goertz DE. Threshold-dependent nonlinear scattering from porphyrin nanobubbles for vascular and extravascular applications. ACTA ACUST UNITED AC 2018; 63:215001. [DOI: 10.1088/1361-6560/aae571] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
12
|
Liu HC, Li Y, Chen R, Jung H, Shung KK. Single-Beam Acoustic Trapping of Red Blood Cells and Polystyrene Microspheres in Flowing Red Blood Cell Saline and Plasma Suspensions. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:852-859. [PMID: 28236533 DOI: 10.1016/j.ultrasmedbio.2016.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 12/01/2016] [Accepted: 12/09/2016] [Indexed: 06/06/2023]
Abstract
Single-beam acoustic tweezers (SBATs) represent a new technology for particle and cell trapping. The advantages of SBATs are their deep penetration into tissues, reduction of tissue damage and ease of application to in vivo studies. The use of these tools for applications in drug delivery in vivo must meet the following conditions: large penetration depth, strong trapping force and tissue safety. A reasonable penetration depth for SBATs in the development of in vivo applications was established in a previous study conducted in water with zero velocity. However, capturing objects in flowing fluid can provide more meaningful results. In this study, we investigated the capability of SBATs to trap red blood cells (RBCs) and polystyrene microspheres in flowing RBC suspensions. Two different types of RBC suspension were prepared in this work: an RBC phosphate-buffered saline (PBS) suspension and an RBC plasma suspension. The results indicated that SBATs successfully trapped RBCs and polystyrene microspheres in a flowing RBC PBS suspension with an average steady velocity of 1.6 cm/s in a 2-mm-diameter polyimide. Furthermore, SBATs were found able to trap RBCs in a flowing RBC PBS suspension at speeds as high as 7.9 cm/s in a polyimide tube, which is higher than the velocity in capillaries (0.03 cm/s) and approaches the velocity in arterioles and venules. Moreover, the results also indicated that polystyrene microspheres can be trapped in an RBC plasma suspension, where aggregation is observed. This work represents a step forward in using this tool in actual in vivo experimentation.
Collapse
Affiliation(s)
- Hsiao-Chuan Liu
- Department of Biomedical Engineering and NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, California, USA; Hematology and Oncology, Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Ying Li
- Department of Biomedical Engineering and NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, California, USA.
| | - Ruimin Chen
- Department of Biomedical Engineering and NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, California, USA
| | - Hayong Jung
- Department of Biomedical Engineering and NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, California, USA
| | - K Kirk Shung
- Department of Biomedical Engineering and NIH Ultrasonic Transducer Resource Center, University of Southern California, Los Angeles, California, USA.
| |
Collapse
|
13
|
Daeichin V, van Rooij T, Skachkov I, Ergin B, Specht PAC, Lima A, Ince C, Bosch JG, van der Steen AFW, de Jong N, Kooiman K. Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging: In Vitro and In Vivo Evaluation. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2017; 64:555-567. [PMID: 28113312 DOI: 10.1109/tuffc.2016.2640342] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Although high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited commercially available UCAs for high-frequency CEUS (hfCEUS) is largely unknown, while shell properties have been shown to be an important factor for their performance. The aim of our study was to produce UCAs in-house for hfCEUS. Twelve different UCA formulations A-L were made by either sonication or mechanical agitation. The gas core consisted of C4F10 and the main coating lipid was either 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC; A-F formulation) or 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC; G-L formulation). Mechanical agitation resulted in UCAs with smaller microbubbles (number weighted mean diameter ~1 [Formula: see text]) than sonication (number weighted mean diameter ~2 [Formula: see text]). UCA formulations with similar size distributions but different main lipid components showed that the DPPC-based UCA formulations had higher nonlinear responses at both the fundamental and subharmonic frequencies in vitro for hfCEUS using the Vevo2100 high-frequency preclinical scanner (FUJIFILM VisualSonics, Inc.). In addition, UCA formulations F (DSPC-based) and L (DPPC-based) that were made by mechanical agitation performed similar in vitro to the commercially available Target-Ready MicroMarker (FUJIFILM VisualSonics, Inc.). UCA formulation F also performed similar to Target-Ready MicroMarker in vivo in pigs with similar mean contrast intensity within the kidney ( n = 7 ), but formulation L did not. This is likely due to the lower stability of formulation L in vivo. Our study shows that DSPC-based microbubbles produced by mechanical agitation resulted in small microbubbles with high nonlinear responses suitable for hfCEUS imaging.
Collapse
|
14
|
Helfield B, Chen X, Qin B, Villanueva FS. Individual lipid encapsulated microbubble radial oscillations: Effects of fluid viscosity. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2016; 139:204-14. [PMID: 26827018 PMCID: PMC4714991 DOI: 10.1121/1.4939123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Ultrasound-stimulated microbubble dynamics have been shown to be dependent on intrinsic bubble properties, including size and shell characteristics. The effect of the surrounding environment on microbubble response, however, has been less investigated. In particular, microbubble optimization studies are generally conducted in water/saline, characterized by a 1 cP viscosity, for application in the vasculature (i.e., 4 cP). In this study, ultra-high speed microscopy was employed to investigate fluid viscosity effects on phospholipid encapsulated microbubble oscillations at 1 MHz, using a single, eight-cycle pulse at peak negative pressures of 100 and 250 kPa. Microbubble oscillations were shown to be affected by fluid viscosity in a size- and pressure-dependent manner. In general, the oscillation amplitudes exhibited by microbubbles between 3 and 6 μm in 1 cP fluid were larger than in 4 cP fluid, reaching a maximum of 1.7-fold at 100 kPa for microbubbles 3.8 μm in diameter and 1.35-fold at 250 kPa for microbubbles 4.8 μm in diameter. Simulation results were in broad agreement at 250 kPa, however generally underestimated the effect of fluid viscosity at 100 kPa. This is the first experimental demonstration documenting the effects of surrounding fluid viscosity on microbubble oscillations, resulting in behavior not entirely predicted by current microbubble models.
Collapse
Affiliation(s)
- Brandon Helfield
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213, USA
| | - Xucai Chen
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213, USA
| | - Bin Qin
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213, USA
| | - Flordeliza S Villanueva
- Center for Ultrasound Molecular Imaging and Therapeutics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15213, USA
| |
Collapse
|
15
|
Raymond JL, Luan Y, van Rooij T, Kooiman K, Huang SL, McPherson DD, Versluis M, de Jong N, Holland CK. Impulse response method for characterization of echogenic liposomes. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2015; 137:1693-703. [PMID: 25920822 PMCID: PMC4417017 DOI: 10.1121/1.4916277] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 03/04/2015] [Accepted: 03/05/2015] [Indexed: 05/21/2023]
Abstract
An optical characterization method is presented based on the use of the impulse response to characterize the damping imparted by the shell of an air-filled ultrasound contrast agent (UCA). The interfacial shell viscosity was estimated based on the unforced decaying response of individual echogenic liposomes (ELIP) exposed to a broadband acoustic impulse excitation. Radius versus time response was measured optically based on recordings acquired using an ultra-high-speed camera. The method provided an efficient approach that enabled statistical measurements on 106 individual ELIP. A decrease in shell viscosity, from 2.1 × 10(-8) to 2.5 × 10(-9) kg/s, was observed with increasing dilatation rate, from 0.5 × 10(6) to 1 × 10(7) s(-1). This nonlinear behavior has been reported in other studies of lipid-shelled UCAs and is consistent with rheological shear-thinning. The measured shell viscosity for the ELIP formulation used in this study [κs = (2.1 ± 1.0) × 10(-8) kg/s] was in quantitative agreement with previously reported values on a population of ELIP and is consistent with other lipid-shelled UCAs. The acoustic response of ELIP therefore is similar to other lipid-shelled UCAs despite loading with air instead of perfluorocarbon gas. The methods described here can provide an accurate estimate of the shell viscosity and damping for individual UCA microbubbles.
Collapse
Affiliation(s)
- Jason L Raymond
- Biomedical Engineering Program, University of Cincinnati, Cardiovascular Center 3940, 231 Albert Sabin Way, Cincinnati, Ohio 45267-0586
| | - Ying Luan
- Department of Biomedical Engineering, Thoraxcenter, Erasmus Medical Center, P.O. Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Tom van Rooij
- Department of Biomedical Engineering, Thoraxcenter, Erasmus Medical Center, P.O. Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Klazina Kooiman
- Department of Biomedical Engineering, Thoraxcenter, Erasmus Medical Center, P.O. Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Shao-Ling Huang
- Department of Internal Medicine, Division of Cardiology, University of Texas Health Science Center, Houston, Texas 77030
| | - David D McPherson
- Department of Internal Medicine, Division of Cardiology, University of Texas Health Science Center, Houston, Texas 77030
| | - Michel Versluis
- Physics of Fluids Group, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500 AE, Enschede, Netherlands
| | - Nico de Jong
- Department of Biomedical Engineering, Thoraxcenter, Erasmus Medical Center, P.O. Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Christy K Holland
- Department of Internal Medicine, Division of Cardiovascular Health and Disease and Biomedical Engineering Program, University of Cincinnati, Cardiovascular Center 3935, 231 Albert Sabin Way, Cincinnati, Ohio 45267-0586
| |
Collapse
|