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Liao M, Zhang Q, Huang J, Huang X, Cheng C, Tu J, Zhang D, Lu Q, Ma L. Near-infrared and ultrasound triggered Pt/Pd-engineered cluster bombs for the treatment of solid tumors. J Control Release 2024; 375:331-345. [PMID: 39278358 DOI: 10.1016/j.jconrel.2024.09.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2024] [Revised: 09/10/2024] [Accepted: 09/11/2024] [Indexed: 09/18/2024]
Abstract
Owing to the dense extracellular matrix and high interstitial fluid pressure in the tumor microenvironment, methods which enhance the permeation and retention of nano drugs into liver tumors remain unsatisfactory for successful tumor treatment. We designed a near-infrared (NIR)- and ultrasound (US)-triggered Pt/Pd-engineered "cluster bomb" (Pt/Pd-CB) which actively penetrates liver cancer cell membranes and achieves photothermal and sonodynamic therapy (SDT). The physical forces generated by the fast expansion and collapse of perfluoropentane nanodroplets eject "sub bombs" (Pt/Pd nanoalloys) into liver cancer cells upon activation by NIR and US. Pt/Pd nanoalloys can then convert H2O2 into O2 to alleviate hypoxia and boost SDT efficiency while exhibiting a highly efficient photothermal response under NIR irradiation. Our findings might especially be promising for the treatment of solid tumors.
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Affiliation(s)
- Min Liao
- Department of Medical Ultrasound, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Qi Zhang
- School of Physics, Nanjing University, Nanjing 210093, China
| | - Jianbo Huang
- Department of Medical Ultrasound, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Xiaotong Huang
- Department of Medical Ultrasound, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Chong Cheng
- College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
| | - Juan Tu
- School of Physics, Nanjing University, Nanjing 210093, China
| | - Dong Zhang
- School of Physics, Nanjing University, Nanjing 210093, China.
| | - Qiang Lu
- Department of Medical Ultrasound, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China.
| | - Lang Ma
- Department of Medical Ultrasound, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China.
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Riaz R, Shafiq S, Fatima M, Siddique MA, Shah S, Abbas SR. Contrast efficacy of novel phase convertible nanodroplets for safe CEUS imaging. Sci Rep 2024; 14:16126. [PMID: 38997313 PMCID: PMC11245480 DOI: 10.1038/s41598-024-66163-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 06/27/2024] [Indexed: 07/14/2024] Open
Abstract
Microbubble contrast agents in ultrasound/echocardiography are used to increase the echogenicity of the target tissues, thereby raising the contrast resolution of the resultant image. Recently, the trend has shifted toward the development of phase-convertible nanodroplets as ultrasound contrast agents due to their promising theragnostic potential by switching capability at the active site. Herein, we fabricated pre-PGS- perfluoropentane phase convertible nanodroplets and checked their in vitro and in vivo enhancement and safety profile. For this, we performed experiments on 20 male Wistar rats and 2 dogs. Biochemical assays of both rats and dogs included complete blood profiles, liver function tests, and renal function tests. For rat vitals, monitoring and histopathological analysis were also performed. Converted nanodroplets showed excellent contrast enhancement, better than Sonovue upon in vitro testing, with an enhancement time of up to 14 min. In vivo, experiments showed comparable opacification of the ventricles of both rats and dogs. All biochemical assays remained within the normal range during the study period. The histopathological analysis did not show any signs of drug-induced toxicity, showing the safety of these nanodroplets. Pre-PGS-PFP nanodroplets hold great potential for use in echocardiography and abdominal imaging in both human and veterinary applications after clinical trials.
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Affiliation(s)
- R Riaz
- Department of Microbiology and Industrial Biotechnology, Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan
- Medical Imaging Technology, FRAHS, Riphah International University, Islamabad, Pakistan
- Biosensors and Therapeutics Lab, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - S Shafiq
- Department of Microbiology and Industrial Biotechnology, Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - M Fatima
- Department of Microbiology and Industrial Biotechnology, Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan
- Biosensors and Therapeutics Lab, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - M A Siddique
- Faculty of Veterinary & Animal Sciences, PMAS UAAR; Maaz Pet Hospital, Rawalpindi, Pakistan
| | - S Shah
- Shifa International Hospital, Islamabad, Pakistan
| | - S R Abbas
- Department of Microbiology and Industrial Biotechnology, Atta ur Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan.
- Biosensors and Therapeutics Lab, School of Interdisciplinary Engineering and Sciences (SINES), National University of Sciences and Technology (NUST), Islamabad, Pakistan.
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3
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Melich R, Emmel P, Vivien A, Sechaud F, Mandaroux C, Mhedhbi S, Bussat P, Tardy I, Cherkaoui S. In Vitro and In Vivo Behavioral Evaluation of Condensed Lipid-Coated Perfluorocarbon Nanodroplets. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:1010-1019. [PMID: 38637170 DOI: 10.1016/j.ultrasmedbio.2024.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 03/08/2024] [Accepted: 03/21/2024] [Indexed: 04/20/2024]
Abstract
OBJECTIVE Phase-shift contrast agents consist of a liquid perfluorocarbon core that can be vaporized by ultrasound to generate echogenic contrast with excellent spatiotemporal control. The purpose of the present work was to evaluate the in vitro and in vivo behavior of condensed lipid-shelled nanodroplets (NDs) using different analytical procedures. METHODS Perfluorobutane NDs were prepared by condensation of precursor fluorescently labeled lipid-shelled microbubbles (MBs) and were characterized in terms of size distribution, gas core content and in vitro stability in blood, as well as for their acoustic vaporization behavior using a custom-made setup. In particular, the in vivo behavior of the NDs was thoroughly investigated after intravenous bolus injection in rats. To this end, we report, for the first time, the efficient use of three complementary detection procedures to assess the in vivo persistence of NDs: (i) ultrasound contrast imaging of vaporized NDs, (ii) gas chromatography-mass spectrometry to determine the perfluorobutane core content and (iii) fluorescence intensity measurement in the collected blood samples. RESULTS The Coulter Counter Multisizer results confirmed the size distribution shift post-condensation. Furthermore, similar PFB concentrations from MB and ND suspensions were obtained, indicating an exceptionally low rate of MB breakage and spontaneous nanodroplet vaporization. As expected, these nanoscale droplets have longer circulation times compared with clinically approved MBs, and only slight variations in half-life were observed between the three monitoring procedures. Finally, echogenic signal observed in focal areas of the liver and spleen after vaporization was confirmed by accumulation of fluorescent nanodroplets in these organs. CONCLUSION These results further contribute to our understanding of both the in vitro and in vivo behavior of sono-responsive nanodroplets, which is key to enabling efficient clinical translation.
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Hallam KA, Nikolai RJ, Jhunjhunwala A, Emelianov SY. Laser-activated perfluorocarbon nanodroplets for intracerebral delivery and imaging via blood-brain barrier opening and contrast-enhanced imaging. J Nanobiotechnology 2024; 22:356. [PMID: 38902773 PMCID: PMC11191388 DOI: 10.1186/s12951-024-02601-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 05/28/2024] [Indexed: 06/22/2024] Open
Abstract
BACKGROUND Ultrasound and photoacoustic (US/PA) imaging is a promising tool for in vivo visualization and assessment of drug delivery. However, the acoustic properties of the skull limit the practical application of US/PA imaging in the brain. To address the challenges in targeted drug delivery to the brain and transcranial US/PA imaging, we introduce and evaluate an intracerebral delivery and imaging strategy based on the use of laser-activated perfluorocarbon nanodroplets (PFCnDs). METHODS Two specialized PFCnDs were developed to facilitate blood‒brain barrier (BBB) opening and contrast-enhanced US/PA imaging. In mice, PFCnDs were delivered to brain tissue via PFCnD-induced BBB opening to the right side of the brain. In vivo, transcranial US/PA imaging was performed to evaluate the utility of PFCnDs for contrast-enhanced imaging through the skull. Ex vivo, volumetric US/PA imaging was used to characterize the spatial distribution of PFCnDs that entered brain tissue. Immunohistochemical analysis was performed to confirm the spatial extent of BBB opening and the accuracy of the imaging results. RESULTS In vivo, transcranial US/PA imaging revealed localized photoacoustic (PA) contrast associated with delivered PFCnDs. In addition, contrast-enhanced ultrasound (CEUS) imaging confirmed the presence of nanodroplets within the same area. Ex vivo, volumetric US/PA imaging revealed PA contrast localized to the area of the brain where PFCnD-induced BBB opening had been performed. Immunohistochemical analysis revealed that the spatial distribution of immunoglobulin (IgG) extravasation into the brain closely matched the imaging results. CONCLUSIONS Using our intracerebral delivery and imaging strategy, PFCnDs were successfully delivered to a targeted area of the brain, and they enabled contrast-enhanced US/PA imaging through the skull. Ex vivo imaging, and immunohistochemistry confirmed the accuracy and precision of the approach.
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Affiliation(s)
- Kristina A Hallam
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Robert J Nikolai
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
| | - Anamik Jhunjhunwala
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
| | - Stanislav Y Emelianov
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA.
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
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Carlier B, Heymans SV, Nooijens S, Collado-Lara G, Toumia Y, Delombaerde L, Paradossi G, D’hooge J, Van Den Abeele K, Sterpin E, Himmelreich U. A Preliminary Investigation of Radiation-Sensitive Ultrasound Contrast Agents for Photon Dosimetry. Pharmaceuticals (Basel) 2024; 17:629. [PMID: 38794199 PMCID: PMC11125270 DOI: 10.3390/ph17050629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/28/2024] [Accepted: 04/30/2024] [Indexed: 05/26/2024] Open
Abstract
Radiotherapy treatment plans have become highly conformal, posing additional constraints on the accuracy of treatment delivery. Here, we explore the use of radiation-sensitive ultrasound contrast agents (superheated phase-change nanodroplets) as dosimetric radiation sensors. In a series of experiments, we irradiated perfluorobutane nanodroplets dispersed in gel phantoms at various temperatures and assessed the radiation-induced nanodroplet vaporization events using offline or online ultrasound imaging. At 25 °C and 37 °C, the nanodroplet response was only present at higher photon energies (≥10 MV) and limited to <2 vaporization events per cm2 per Gy. A strong response (~2000 vaporizations per cm2 per Gy) was observed at 65 °C, suggesting radiation-induced nucleation of the droplet core at a sufficiently high degree of superheat. These results emphasize the need for alternative nanodroplet formulations, with a more volatile perfluorocarbon core, to enable in vivo photon dosimetry. The current nanodroplet formulation carries potential as an innovative gel dosimeter if an appropriate gel matrix can be found to ensure reproducibility. Eventually, the proposed technology might unlock unprecedented temporal and spatial resolution in image-based dosimetry, thanks to the combination of high-frame-rate ultrasound imaging and the detection of individual vaporization events, thereby addressing some of the burning challenges of new radiotherapy innovations.
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Affiliation(s)
- Bram Carlier
- Department of Oncology, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (B.C.); (L.D.); (E.S.)
- Department of Imaging and Pathology, KU Leuven-University of Leuven, 3000 Leuven, Belgium
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven-University of Leuven, 3000 Leuven, Belgium
| | - Sophie V. Heymans
- Department of Physics, KU Leuven Campus Kortrijk—KULAK, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium; (S.V.H.); (K.V.D.A.)
- Department of Cardiovascular Sciences, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (S.N.); (J.D.)
| | - Sjoerd Nooijens
- Department of Cardiovascular Sciences, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (S.N.); (J.D.)
| | - Gonzalo Collado-Lara
- Department of Cardiology, Erasmus MC University Medical Center, 3015 GD Rotterdam, The Netherlands;
| | - Yosra Toumia
- National Institute for Nuclear Physics, INFN Sezione di Roma Tor Vergata, 00133 Rome, Italy;
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, 00133 Rome, Italy;
| | - Laurence Delombaerde
- Department of Oncology, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (B.C.); (L.D.); (E.S.)
- Department of Radiotherapy, UH Leuven, 3000 Leuven, Belgium
| | - Gaio Paradossi
- Department of Chemical Science and Technologies, University of Rome Tor Vergata, 00133 Rome, Italy;
| | - Jan D’hooge
- Department of Cardiovascular Sciences, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (S.N.); (J.D.)
| | - Koen Van Den Abeele
- Department of Physics, KU Leuven Campus Kortrijk—KULAK, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium; (S.V.H.); (K.V.D.A.)
| | - Edmond Sterpin
- Department of Oncology, KU Leuven-University of Leuven, 3000 Leuven, Belgium; (B.C.); (L.D.); (E.S.)
- Particle Therapy Interuniversity Center Leuven—PARTICLE, 3000 Leuven, Belgium
| | - Uwe Himmelreich
- Department of Imaging and Pathology, KU Leuven-University of Leuven, 3000 Leuven, Belgium
- Molecular Small Animal Imaging Center (MoSAIC), KU Leuven-University of Leuven, 3000 Leuven, Belgium
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Ji Y, Zheng J, Geng Z, Wang X, Hou Y, Tian J, Hu J, Zhang Y, Zhang L. Fluorocarbon Nanodroplets: Their Formation and Stability in Complex Solution Systems. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:9108-9119. [PMID: 38632937 DOI: 10.1021/acs.langmuir.4c00475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Perfluorocarbon (PFC) nanodroplets (NDs) are expanding in a wide range of applications in biotechnology and nanotechnology. Their efficacy in biological systems is significantly influenced by their size uniformity and stability within bioelectrolyte contexts. Presently, methods for creating monodisperse, highly concentrated, and well-stabilized PFC NDs under harsh conditions using low energy consumption methods have not been thoroughly developed, and their stability has not been sufficiently explored. This gap restricts their applicability for advanced medical interventions in tissues with high pH levels and various electrolytic conditions. To tackle these challenges and to circumvent potential toxicity from surface stabilizers, we have conducted an in-depth investigation into the formation and stability of uncoated perfluorohexane (PFH) NDs, which were synthesized by using a low-energy consumption solvent exchange technique, across complex electrolyte compositions or a broad spectrum of pH levels. The results indicated that low concentrations of low-valent electrolyte ions facilitate the nucleation of NDs and consistently accelerate Ostwald ripening over an extended period. Conversely, high concentrations of highly valent electrolyte ions inhibit nucleation and decelerate the ripening process over time. Given the similarities between the properties of NDs and nanobubbles, we propose a potential stabilization mechanism. Electrolytes influence the Ostwald ripening of NDs by adjusting the adsorption and distribution of ions on the NDs' surface, modifying the thickness of the electric double layer, and fine-tuning the energy barrier between droplets. These insights enable precise control over the stability of PFC NDs through the meticulous adjustment of the surrounding electrolyte composition. This offers an effective preparation method and a theoretical foundation for employing bare PFC NDs in physiological settings.
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Affiliation(s)
- Yuwen Ji
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jin Zheng
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhanli Geng
- Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, Qinghai 810008, China
- Qinghai Provincial Key Laboratory of Resources and Chemistry of Salt Lakes, Xining, Qinghai 810008, China
| | - Xingya Wang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yangqian Hou
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiakun Tian
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Hu
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
- Institute of Materiobiology, College of Science, Shanghai University, Shanghai 200444, China
- Xiangfu Laboratory, Jiashan 314102, China
| | - Yi Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lijuan Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Pellow C, Jafari Sojahrood A, Zhao X, Kolios MC, Exner AA, Goertz DE. Synchronous Intravital Imaging and Cavitation Monitoring of Antivascular Focused Ultrasound in Tumor Microvasculature Using Monodisperse Low Boiling Point Nanodroplets. ACS NANO 2024; 18:410-427. [PMID: 38147452 PMCID: PMC10786165 DOI: 10.1021/acsnano.3c07711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 12/18/2023] [Accepted: 12/20/2023] [Indexed: 12/28/2023]
Abstract
Focused ultrasound-stimulated microbubbles can induce blood flow shutdown and ischemic necrosis at higher pressures in an approach termed antivascular ultrasound. Combined with conventional therapies of chemotherapy, immunotherapy, and radiation therapy, this approach has demonstrated tumor growth inhibition and profound synergistic antitumor effects. However, the lower cavitation threshold of microbubbles can potentially yield off-target damage that the polydispersity of clinical agent may further exacerbate. Here we investigate the use of a monodisperse nanodroplet formulation for achieving antivascular effects in tumors. We first develop stable low boiling point monodisperse lipid nanodroplets and examine them as an alternative agent to mediate antivascular ultrasound. With synchronous intravital imaging and ultrasound monitoring of focused ultrasound-stimulated nanodroplets in tumor microvasculature, we show that nanodroplets can trigger blood flow shutdown and do so with a sharper pressure threshold and with fewer additional events than conventionally used microbubbles. We further leverage the smaller size and prolonged pharmacokinetic profile of nanodroplets to allow for potential passive accumulation in tumor tissue prior to antivascular ultrasound, which may be a means by which to promote selective tumor targeting. We find that vascular shutdown is accompanied by inertial cavitation and complex-order sub- and ultraharmonic acoustic signatures, presenting an opportunity for effective feedback control of antivascular ultrasound.
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Affiliation(s)
- Carly Pellow
- Sunnybrook Research Institute, Toronto M4N 3M5, Canada
| | - Amin Jafari Sojahrood
- Sunnybrook Research Institute, Toronto M4N 3M5, Canada
- Department of Physics, Toronto Metropolitan University, Toronto M5B 2K3, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), a partnership between St. Michael's Hospital, a site of Unity Health Toronto and Toronto Metropolitan University, Toronto M5B 1T8, Canada
| | - Xiaoxiao Zhao
- Sunnybrook Research Institute, Toronto M4N 3M5, Canada
- Department of Medical Biophysics, University of Toronto, Toronto M5G 1L7, Canada
| | - Michael C Kolios
- Department of Physics, Toronto Metropolitan University, Toronto M5B 2K3, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), a partnership between St. Michael's Hospital, a site of Unity Health Toronto and Toronto Metropolitan University, Toronto M5B 1T8, Canada
| | - Agata A Exner
- Department of Radiology, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - David E Goertz
- Sunnybrook Research Institute, Toronto M4N 3M5, Canada
- Department of Medical Biophysics, University of Toronto, Toronto M5G 1L7, Canada
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Purohit MP, Roy KS, Xiang Y, Yu BJ, Azadian MM, Muwanga G, Hart AR, Taoube AK, Lopez DG, Airan RD. Acoustomechanically activatable liposomes for ultrasonic drug uncaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.23.563690. [PMID: 37961368 PMCID: PMC10634775 DOI: 10.1101/2023.10.23.563690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Ultrasound-activatable drug-loaded nanocarriers enable noninvasive and spatiotemporally-precise on-demand drug delivery throughout the body. However, most systems for ultrasonic drug uncaging utilize cavitation or heating as the drug release mechanism and often incorporate relatively exotic excipients into the formulation that together limit the drug-loading potential, stability, and clinical translatability and applicability of these systems. Here we describe an alternate strategy for the design of such systems in which the acoustic impedance and osmolarity of the internal liquid phase of a drug-loaded particle is tuned to maximize ultrasound-induced drug release. No gas phase, cavitation, or medium heating is necessary for the drug release mechanism. Instead, a non-cavitation-based mechanical response to ultrasound mediates the drug release. Importantly, this strategy can be implemented with relatively common pharmaceutical excipients, as we demonstrate here by implementing this mechanism with the inclusion of a few percent sucrose into the internal buffer of a liposome. Further, the ultrasound protocols sufficient for in vivo drug uncaging with this system are achievable with current clinical therapeutic ultrasound systems and with intensities that are within FDA and society guidelines for safe transcranial ultrasound application. Finally, this current implementation of this mechanism should be versatile and effective for the loading and uncaging of any therapeutic that may be loaded into a liposome, as we demonstrate for four different drugs in vitro, and two in vivo. These acoustomechanically activatable liposomes formulated with common pharmaceutical excipients promise a system with high clinical translational potential for ultrasonic drug uncaging of myriad drugs of clinical interest.
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Affiliation(s)
| | - Kanchan Sinha Roy
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
| | - Yun Xiang
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
| | - Brenda J. Yu
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Biophysics Program, Stanford University, Stanford, CA, 94305 USA
| | - Matine M. Azadian
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Neurosciences Program, Stanford University, Stanford, CA, 94305 USA
| | - Gabriella Muwanga
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Neurosciences Program, Stanford University, Stanford, CA, 94305 USA
| | - Alex R. Hart
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Department of Chemistry, Stanford University, Stanford, CA, 94305 USA
| | - Ali K. Taoube
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
| | - Diego Gomez Lopez
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Department of Medicine, Health, and Society, Vanderbilt University, Nashville, TN 37235 USA
| | - Raag D. Airan
- Department of Radiology, Stanford University, Stanford, CA, 94305 USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, 94305 USA
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305 USA
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9
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Zhang W, Metzger H, Vlatakis S, Claxton A, Carbajal MA, Fung LF, Mason J, Chan KLA, Pouliopoulos AN, Fleck RA, Prentice P, Thanou M. Characterising the chemical and physical properties of phase-change nanodroplets. ULTRASONICS SONOCHEMISTRY 2023; 97:106445. [PMID: 37257208 PMCID: PMC10241977 DOI: 10.1016/j.ultsonch.2023.106445] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 06/02/2023]
Abstract
Phase-change nanodroplets have attracted increasing interest in recent years as ultrasound theranostic nanoparticles. They are smaller compared to microbubbles and they may distribute better in tissues (e.g. in tumours). They are composed of a stabilising shell and a perfluorocarbon core. Nanodroplets can vaporise into echogenic microbubbles forming cavitation nuclei when exposed to ultrasound. Their perfluorocarbon core phase-change is responsible for the acoustic droplet vaporisation. However, methods to quantify the perfluorocarbon core in nanodroplets are lacking. This is an important feature that can help explain nanodroplet phase change characteristics. In this study, we fabricated nanodroplets using lipids shell and perfluorocarbons. To assess the amount of perfluorocarbon in the core we used two methods, 19F NMR and FTIR. To assess the cavitation after vaporisation we used an ultrasound transducer (1.1 MHz) and a high-speed camera. The 19F NMR based method showed that the fluorine signal correlated accurately with the perfluorocarbon concentration. Using this correlation, we were able to quantify the perfluorocarbon core of nanodroplets. This method was used to assess the content of the perfluorocarbon of the nanodroplets in solutions over time. It was found that perfluoropentane nanodroplets lost their content faster and at higher ratio compared to perfluorohexane nanodroplets. The high-speed imaging indicates that the nanodroplets generate cavitation comparable to that from commercial contrast agent microbubbles. Nanodroplet characterisation should include perfluorocarbon concentration assessment as critical information for their development.
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Affiliation(s)
- Weiqi Zhang
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom
| | - Hilde Metzger
- School of Engineering, University of Glasgow, United Kingdom
| | - Stavros Vlatakis
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom
| | - Amelia Claxton
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom
| | | | - Leong Fan Fung
- Department of Surgical & Interventional Engineering, King's College London, United Kingdom
| | - James Mason
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom
| | - K L Andrew Chan
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom
| | | | - Roland A Fleck
- Centre for Ultrastructural Imaging, King's College London, United Kingdom
| | - Paul Prentice
- School of Engineering, University of Glasgow, United Kingdom
| | - Maya Thanou
- Institute of Cancer & Pharmaceutical Sciences, King's College London, United Kingdom.
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10
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Bautista KJB, Kim J, Xu Z, Jiang X, Dayton PA. Current Status of Sub-micron Cavitation-Enhancing Agents for Sonothrombolysis. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:1049-1057. [PMID: 36868959 DOI: 10.1016/j.ultrasmedbio.2023.01.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/11/2023] [Accepted: 01/23/2023] [Indexed: 05/11/2023]
Abstract
Thrombosis in cardiovascular disease is an urgent global issue, but treatment progress is limited by the risks of current antithrombotic approaches. The cavitation effect in ultrasound-mediated thrombolysis offers a promising mechanical alternative for clot lysis. Further addition of microbubble contrast agents introduces artificial cavitation nuclei that can enhance the mechanical disruption induced by ultrasound. Recent studies have proposed sub-micron particles as novel sonothrombolysis agents with increased spatial specificity, safety and stability for thrombus disruption. In this article, the applications of different sub-micron particles for sonothrombolysis are discussed. Also reviewed are in vitro and in vivo studies that apply these particles as cavitation agents and as adjuvants to thrombolytic drugs. Finally, perspectives on future developments in sub-micron agents for cavitation-enhanced sonothrombolysis are shared.
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Affiliation(s)
- Kathlyne Jayne B Bautista
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC, USA
| | - Jinwook Kim
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC, USA
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Xiaoning Jiang
- Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC, USA
| | - Paul A Dayton
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, NC, USA.
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11
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Microbubbles for human diagnosis and therapy. Biomaterials 2023; 294:122025. [PMID: 36716588 DOI: 10.1016/j.biomaterials.2023.122025] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/17/2023] [Accepted: 01/24/2023] [Indexed: 01/26/2023]
Abstract
Microbubbles (MBs) were observed for the first time in vivo as a curious consequence of quick saline injection during ultrasound (US) imaging of the aortic root, more than 50 years ago. From this serendipitous event, MBs are now widely used as contrast enhancers for US imaging. Their intrinsic properties described in this review, allow a multitude of designs, from shell to gas composition but also from grafting targeting agents to drug payload encapsulation. Indeed, the versatile MBs are deeply studied for their dual potential in imaging and therapy. As presented in this paper, new generations of MBs now opens perspectives for targeted molecular imaging along with the development of new US imaging systems. This review also presents an overview of the different therapeutic strategies with US and MBs for cancer, cardiovascular diseases, and inflammation. The overall aim is to overlap those fields in order to find similarities in the MBs application for treatment enhancement associated with US. To conclude, this review explores the new scales of MBs technologies with nanobubbles development, and along concurrent advances in the US imaging field. This review ends by discussing perspectives for the booming future uses of MBs.
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12
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Collado-Lara G, Heymans SV, Rovituso M, Sterpin E, D'hooge J, Vos HJ, Abeele KVD, de Jong N. Analytic prediction of droplet vaporization events to estimate the precision of ultrasound-based proton range verification. Med Phys 2023. [PMID: 36856326 DOI: 10.1002/mp.16327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 02/14/2023] [Accepted: 02/20/2023] [Indexed: 03/02/2023] Open
Abstract
BACKGROUND The safety and efficacy of proton therapy is currently hampered by range uncertainties. The combination of ultrasound imaging with injectable radiation-sensitive superheated nanodroplets was recently proposed for in vivo range verification. The proton range can be estimated from the distribution of nanodroplet vaporization events, which is stochastically related to the stopping distribution of protons, as nanodroplets are vaporized by protons reaching their maximal LET at the end of their range. PURPOSE Here, we aim to estimate the range estimation precision of this technique. As for any stochastic measurement, the precision will increase with the sample size, that is, the number of detected vaporizations. Thus, we first develop and validate a model to predict the number of vaporizations, which is then applied to estimate the range verification precision for a set of conditions (droplet size, droplet concentration, and proton beam parameters). METHODS Starting from the thermal spike theory, we derived a model that predicts the expected number of droplet vaporizations in an irradiated sample as a function of the droplet size, concentration, and number of protons. The model was validated by irradiating phantoms consisting of size-sorted perfluorobutane droplets dispersed in an aqueous matrix. The number of protons was counted with an ionization chamber, and the droplet vaporizations were recorded and counted individually using high frame rate ultrasound imaging. After validation, the range estimate precision was determined for different conditions using a Monte Carlo algorithm. RESULTS A good agreement between theory and experiments was observed for the number of vaporizations, especially for large (5.8 ± 2.2 µm) and medium (3.5 ± 1.1 µm) sized droplets. The number of events was lower than expected in phantoms with small droplets (2.0 ± 0.7 µm), but still within the same order of magnitude. The inter-phantom variability was considerably larger (up to 30x) than predicted by the model. The validated model was then combined with Monte Carlo simulations, which predicted a theoretical range retrieval precision improving with the square-root of the number of vaporizations, and degrading at high beam energies due to range straggling. For single pencil beams with energies between 70 and 240 MeV, a range verification precision below 1% of the range required perfluorocarbon concentrations in the order of 0.3-2.4 µM. CONCLUSION We proposed and experimentally validated a model to provide a quick estimate of the number of vaporizations for a given set of conditions (droplet size, droplet concentration, and proton beam parameters). From this model, promising range verification performances were predicted for realistic perfluorocarbon concentrations. These findings are an incentive to move towards preclinical studies, which are critical to assess the achievable droplet distribution in and around the tumor, and hence the in vivo range verification precision.
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Affiliation(s)
- Gonzalo Collado-Lara
- Biomedical Engineering, Department of Cardiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Sophie V Heymans
- Biomedical Engineering, Department of Cardiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.,Department of Physics, KU Leuven Campus Kulak, Kortrijk, Belgium.,Department of Cardiovascular Sciences, Leuven KU, Leuven, Belgium
| | | | - Edmond Sterpin
- Department of Oncology, Leuven KU, Leuven, Belgium.,Center of Molecular Imaging, Radiotherapy and Oncology, IREC Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Jan D'hooge
- Department of Cardiovascular Sciences, Leuven KU, Leuven, Belgium
| | - Hendrik J Vos
- Biomedical Engineering, Department of Cardiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | | | - Nico de Jong
- Biomedical Engineering, Department of Cardiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands
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13
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Recent progress in theranostic microbubbles. CHINESE CHEM LETT 2023. [DOI: 10.1016/j.cclet.2023.108137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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14
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Zhang G, Ye HR, Sun Y, Guo ZZ. Ultrasound Molecular Imaging and Its Applications in Cancer Diagnosis and Therapy. ACS Sens 2022; 7:2857-2864. [PMID: 36190830 DOI: 10.1021/acssensors.2c01468] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ultrasound imaging is regarded as a highly sensitive imaging modality used in routine clinical examinations. Over the last several decades, ultrasound contrast agents have been widely applied in ultrasound molecular cancer imaging to improve the detection, characterization, and quantification of tumors. To date, a few new potential preclinical and clinical applications regarding ultrasound molecular cancer imaging are being investigated. This review presents an overview of the various kinds of ultrasound contrast agents employed in ultrasound molecular imaging and advanced imaging techniques using these contrast agents. Additionally, we discuss the recent enormous development of ultrasound contrast agents in the relevant preclinical and clinical applications, highlight the recent challenges which need to be overcome to accelerate the clinical translation, and discuss the future perspective of ultrasound molecular cancer imaging using various contrast agents. As a highly promising and valuable tumor-specific imaging technique, it is believed that ultrasound molecular imaging will pave an accurate and efficient way for cancer diagnosis.
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Affiliation(s)
- Ge Zhang
- Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, China, 430070.,Department of Medical Ultrasound, China Resources and Wisco General Hospital, Wuhan University of Science and Technology, Wuhan, China, 430080
| | - Hua-Rong Ye
- Department of Medical Ultrasound, China Resources and Wisco General Hospital, Wuhan University of Science and Technology, Wuhan, China, 430080
| | - Yao Sun
- College of Chemistry, Central China Normal University, Wuhan, China, 430079
| | - Zhen-Zhong Guo
- Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Wuhan University of Science and Technology, Wuhan, China, 430070
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15
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Novel Magnetic Elastic Phase-Change Nanodroplets as Dual Mode Contrast Agent for Ultrasound and Magnetic Resonance Imaging. Polymers (Basel) 2022; 14:polym14142915. [PMID: 35890691 PMCID: PMC9318938 DOI: 10.3390/polym14142915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/05/2022] [Accepted: 06/08/2022] [Indexed: 01/25/2023] Open
Abstract
Recently, dual-mode imaging systems merging magnetic resonance imaging (MRI) and ultrasound (US) have been developed. Designing a dual-mode contrast agent is complex due to different mechanisms of enhancement. Herein, we describe novel phase change nanodroplets (PCNDs) with perfluoropentane encapsulated in a pre-polyglycerol sebacate (pre-PGS) shell loaded with polyethylene glycol (PEG)-coated iron oxide nanoparticles as having a dual-mode contrast agent effect. Iron oxide nanoparticles were prepared via the chemical co-precipitation method and PCNDs were prepared via the solvent displacement technique. PCNDs showed excellent enhancement in the in vitro US much more than Sonovue® microbubbles. Furthermore, they caused a susceptibility effect resulting in a reduction of signal intensity on MRI. An increase in the concentration of nanoparticles caused an increase in the MR contrast effect but a reduction in US intensity. The concentration of nanoparticles in a shell of PCNDs was optimized to obtain a dual-mode contrast effect. Biocompatibility, hemocompatibility, and immunogenicity assays showed that PCNDs were safe and non-immunogenic. Another finding was the dual-mode potential of unloaded PCNDs as T1 MR and US contrast agents. Results suggest the excellent potential of these PCNDs for use as dual-mode contrast agents for both MRI and US.
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16
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Jandhyala S, Van Namen A, Spatarelu CP, Luke GP. EGFR-Targeted Perfluorohexane Nanodroplets for Molecular Ultrasound Imaging. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2251. [PMID: 35808089 PMCID: PMC9268413 DOI: 10.3390/nano12132251] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 02/01/2023]
Abstract
Perfluorocarbon nanodroplets offer an alternative to gaseous microbubbles as contrast agents for ultrasound imaging. They can be acoustically activated to induce a liquid-to-gas phase transition and provide contrast in ultrasound images. In this study, we demonstrate a new strategy to synthesize antibody-conjugated perfluorohexane nanodroplet (PFHnD-Ab) ultrasound contrast agents that target cells overexpressing the epidermal growth factor receptor (EGFR). The perfluorohexane nanodroplets (PFHnD) containing a lipophilic DiD fluorescent dye were synthesized using a phospholipid shell. Antibodies were conjugated to the surface through a hydrazide-aldehyde reaction. Cellular binding was confirmed using fluorescence microscopy; the DiD fluorescence signal of the PFHnD-Ab was 5.63× and 6× greater than the fluorescence signal in the case of non-targeted PFHnDs and the EGFR blocking control, respectively. Cells were imaged in tissue-mimicking phantoms using a custom ultrasound imaging setup consisting of a high-intensity focused ultrasound transducer and linear array imaging transducer. Cells with conjugated PFHnD-Abs exhibited a significantly higher (p < 0.001) increase in ultrasound amplitude compared to cells with non-targeted PFHnDs and cells exposed to free antibody before the addition of PFHnD-Abs. The developed nanodroplets show potential to augment the use of ultrasound in molecular imaging cancer diagnostics.
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Affiliation(s)
- Sidhartha Jandhyala
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA; (S.J.); (A.V.N.); (C.-P.S.)
| | - Austin Van Namen
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA; (S.J.); (A.V.N.); (C.-P.S.)
| | - Catalina-Paula Spatarelu
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA; (S.J.); (A.V.N.); (C.-P.S.)
| | - Geoffrey P. Luke
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA; (S.J.); (A.V.N.); (C.-P.S.)
- Translational Engineering in Cancer Program, Dartmouth Cancer Center, Lebanon, NH 03756, USA
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17
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Heymans SV, Collado-Lara G, Rovituso M, Vos HJ, D'hooge J, de Jong N, Van Abeele KD. Acoustic Modulation Enables Proton Detection With Nanodroplets at Body Temperature. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:2028-2038. [PMID: 35385380 DOI: 10.1109/tuffc.2022.3164805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Superheated nanodroplet (ND) vaporization by proton radiation was recently demonstrated, opening the door to ultrasound-based in vivo proton range verification. However, at body temperature and physiological pressures, perfluorobutane nanodroplets (PFB-NDs), which offer a good compromise between stability and radiation sensitivity, are not directly sensitive to primary protons. Instead, they are vaporized by infrequent secondary particles, which limits the precision for range verification. The radiation-induced vaporization threshold (i.e., sensitization threshold) can be reduced by lowering the pressure in the droplet such that ND vaporization by primary protons can occur. Here, we propose to use an acoustic field to modulate the pressure, intermittently lowering the proton sensitization threshold of PFB-NDs during the rarefactional phase of the ultrasound wave. Simultaneous proton irradiation and sonication with a 1.1 MHz focused transducer, using increasing peak negative pressures (PNPs), were applied on a dilution of PFB-NDs flowing in a tube, while vaporization was acoustically monitored with a linear array. Sensitization to primary protons was achieved at temperatures between [Formula: see text] and 40 °C using acoustic PNPs of relatively low amplitude (from 800 to 200 kPa, respectively), while sonication alone did not lead to ND vaporization at those PNPs. Sensitization was also measured at the clinically relevant body temperature (i.e., 37 °C) using a PNP of 400 kPa. These findings confirm that acoustic modulation lowers the sensitization threshold of superheated NDs, enabling a direct proton response at body temperature.
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18
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Zhang W, Shi Y, Abd Shukor S, Vijayakumaran A, Vlatakis S, Wright M, Thanou M. Phase-shift nanodroplets as an emerging sonoresponsive nanomaterial for imaging and drug delivery applications. NANOSCALE 2022; 14:2943-2965. [PMID: 35166273 DOI: 10.1039/d1nr07882h] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Nanodroplets - emerging phase-changing sonoresponsive materials - have attracted substantial attention in biomedical applications for both tumour imaging and therapeutic purposes due to their unique response to ultrasound. As ultrasound is applied at different frequencies and powers, nanodroplets have been shown to cavitate by the process of acoustic droplet vapourisation (ADV), causing the development of mechanical forces which promote sonoporation through cellular membranes. This allows drugs to be delivered efficiently into deeper tissues where tumours are located. Recent reviews on nanodroplets are mostly focused on the mechanism of cavitation and their applications in biomedical fields. However, the chemistry of the nanodroplet components has not been discussed or reviewed yet. In this review, the commonly used materials and preparation methods of nanodroplets are summarised. More importantly, this review provides examples of variable chemistry components in nanodroplets which link them to their efficiency as ultrasound-multimodal imaging agents to image and monitor drug delivery. Finally, the drawbacks of current research, future development, and future direction of nanodroplets are discussed.
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Affiliation(s)
- Weiqi Zhang
- School of Cancer & Pharmaceutical Sciences, King's College London, UK.
| | - Yuhong Shi
- School of Cancer & Pharmaceutical Sciences, King's College London, UK.
| | | | | | - Stavros Vlatakis
- School of Cancer & Pharmaceutical Sciences, King's College London, UK.
| | - Michael Wright
- School of Cancer & Pharmaceutical Sciences, King's College London, UK.
| | - Maya Thanou
- School of Cancer & Pharmaceutical Sciences, King's College London, UK.
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19
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Namen AV, Jandhyala S, Jordan T, Luke GP. Repeated Acoustic Vaporization of Perfluorohexane Nanodroplets for Contrast-Enhanced Ultrasound Imaging. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:3497-3506. [PMID: 34191726 PMCID: PMC8667194 DOI: 10.1109/tuffc.2021.3093828] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Superheated perfluorocarbon nanodroplets are emerging ultrasound imaging contrast agents that boast biocompatible components, unique phase-change dynamics, and therapeutic loading capabilities. Upon exposure to a sufficiently high-intensity pulse of acoustic energy, the nanodroplet's perfluorocarbon core undergoes a liquid-to-gas phase change and becomes an echogenic microbubble, providing ultrasound contrast. The controllable activation leads to high-contrast images, while the small size of the nanodroplets promotes longer circulation times and better in vivo stability. One drawback, however, is that the nanodroplets can only be vaporized a single time, limiting their versatility. Recently, we and others have addressed this issue by using a perfluorohexane core, which has a boiling point above body temperature. Thus after vaporization, the microbubbles recondense back into their stable nanodroplet form. Previous work with perfluorohexane nanodroplets relied on optical activation via pulsed laser absorption of an encapsulated dye. This strategy limits the imaging depth and temporal resolution of the method. In this study, we overcome these limitations by demonstrating acoustic droplet vaporization with 1.1-MHz high-intensity focused ultrasound (HIFU). A short-duration, high-amplitude pulse of focused ultrasound provides a sufficiently strong peak negative pressure to initiate vaporization. A custom imaging sequence was developed to enable the synchronization of a HIFU transducer and a linear array imaging transducer. We show a visualization of repeated acoustic activation of perfluorohexane nanodroplets in polyacrylamide tissue-mimicking phantoms. We further demonstrate the detection of hundreds of vaporization events from individual nanodroplets with activation thresholds well below the tissue cavitation limit. Overall, this approach has the potential to result in reliable and repeatable contrast-enhanced ultrasound imaging at clinically relevant depths.
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20
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Le TNQ, Tran NN, Escribà-Gelonch M, Serra CA, Fisk I, McClements DJ, Hessel V. Microfluidic encapsulation for controlled release and its potential for nanofertilisers. Chem Soc Rev 2021; 50:11979-12012. [PMID: 34515721 DOI: 10.1039/d1cs00465d] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Nanotechnology is increasingly being utilized to create advanced materials with improved or new functional attributes. Converting fertilizers into a nanoparticle-form has been shown to improve their efficacy but the current procedures used to fabricate nanofertilisers often have poor reproducibility and flexibility. Microfluidic systems, on the other hand, have advantages over traditional nanoparticle fabrication methods in terms of energy and materials consumption, versatility, and controllability. The increased controllability can result in the formation of nanoparticles with precise and complex morphologies (e.g., tuneable sizes, low polydispersity, and multi-core structures). As a result, their functional performance can be tailored to specific applications. This paper reviews the principles, formation, and applications of nano-enabled delivery systems fabricated using microfluidic approaches for the encapsulation, protection, and release of fertilizers. Controlled release can be achieved using two main routes: (i) nutrients adsorbed on nanosupports and (ii) nutrients encapsulated inside nanostructures. We aim to highlight the opportunities for preparing a new generation of highly versatile nanofertilisers using microfluidic systems. We will explore several main characteristics of microfluidically prepared nanofertilisers, including droplet formation, shell fine-tuning, adsorbate fine-tuning, and sustained/triggered release behavior.
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Affiliation(s)
- Tu Nguyen Quang Le
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia. .,Faculty of Chemical Engineering, Ho Chi Minh City University of Technology, Ho Chi Minh City, Vietnam
| | - Nam Nghiep Tran
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia. .,School of Chemical Engineering, Can Tho University, Can Tho City, Vietnam
| | - Marc Escribà-Gelonch
- Higher Polytechnic Engineering School, University of Lleida, Igualada (Barcelona), 08700, Spain
| | - Christophe A Serra
- Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22, F-67000 Strasbourg, France
| | - Ian Fisk
- Division of Food, Nutrition and Dietetics, School of Biosciences, University of Nottingham, Loughborough, LE12 5RD, UK.,The University of Adelaide, North Terrace, Adelaide, South Australia, Australia
| | | | - Volker Hessel
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia. .,School of Engineering, University of Warwick, Library Rd, Coventry, UK
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21
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Dong F, An J, Zhang J, Yin J, Guo W, Wang D, Feng F, Huang S, Zhang J, Cheng H. Blinking Acoustic Nanodroplets Enable Fast Super-resolution Ultrasound Imaging. ACS NANO 2021; 15:16913-16923. [PMID: 34647449 DOI: 10.1021/acsnano.1c07896] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The advent of localization-based super-resolution ultrasound (SRUS) imaging creates a vista for precision vasculature and hemodynamic measurements in brain science, cardiovascular diseases, and cancer. As blinking fluorophores are crucial to super-resolution optical imaging, blinking acoustic contrast agents enabling ultrasound localization microscopy have been highly sought, but only with limited success. Here we report on the discovery and characterization of a type of blinking acoustic nanodroplets (BANDs) ideal for SRUS. BANDs of 200-500 nm diameters comprise a perfluorocarbon-filled core and a shell of DSPC, Pluronic F68, and DSPE-PEG2000. When driven by clinically safe acoustic pulses (MI < 1.9) provided by a diagnostic ultrasound transducer, BANDs underwent reversible vaporization and reliquefaction, manifesting as "blinks", at rates of up to 5 kHz. By sparse activation of perfluorohexane-filled BANDs-C6 at high concentrations, only 100 frames of ultrasound imaging were sufficient to reconstruct super-resolution images of a no-flow tube through either cumulative localization or temporal radiality autocorrelation. Furthermore, the use of high-density BANDs-C6-4 (1 × 108/mL) with a 1:9 admixture of perfluorohexane and perfluorobutane supported the fast SRUS imaging of muscle vasculature in live animals, at 64 μm resolution requiring only 100 frames per layer. We anticipate that the BANDs developed here will greatly boost the application of SRUS in both basic science and clinical settings.
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Affiliation(s)
- Feihong Dong
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- State Key Laboratory of Membrane Biology, National Biomedical Imaging Center, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Jian An
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Jiabin Zhang
- State Key Laboratory of Membrane Biology, National Biomedical Imaging Center, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Jingyi Yin
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Wenyu Guo
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Di Wang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Feng Feng
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Shuo Huang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Jue Zhang
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- College of Engineering, Peking University, Beijing 100871, China
- National Biomedical Imaging Center, Peking University, Beijing 100871, China
| | - Heping Cheng
- State Key Laboratory of Membrane Biology, National Biomedical Imaging Center, Peking-Tsinghua Center for Life Sciences, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
- National Biomedical Imaging Center, Peking University, Beijing 100871, China
- Research Unit of Mitochondria in Brain Diseases, Chinese Academy of Medical Sciences, PKU-Nanjing Institute of Translational Medicine, Nanjing 211899, China
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22
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Applications of Ultrasound-Mediated Drug Delivery and Gene Therapy. Int J Mol Sci 2021; 22:ijms222111491. [PMID: 34768922 PMCID: PMC8583720 DOI: 10.3390/ijms222111491] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/11/2021] [Accepted: 10/19/2021] [Indexed: 12/14/2022] Open
Abstract
Gene therapy has continuously evolved throughout the years since its first proposal to develop more specific and effective transfection, capable of treating a myriad of health conditions. Viral vectors are some of the most common and most efficient vehicles for gene transfer. However, the safe and effective delivery of gene therapy remains a major obstacle. Ultrasound contrast agents in the form of microbubbles have provided a unique solution to fulfill the need to shield the vectors from the host immune system and the need for site specific targeted therapy. Since the discovery of the biophysical and biological effects of microbubble sonification, multiple developments have been made to enhance its applicability in targeted drug delivery. The concurrent development of viral vectors and recent research on dual vector strategies have shown promising results. This review will explore the mechanisms and recent advancements in the knowledge of ultrasound-mediated microbubbles in targeting gene and drug therapy.
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23
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Detecting insulitis in type 1 diabetes with ultrasound phase-change contrast agents. Proc Natl Acad Sci U S A 2021; 118:2022523118. [PMID: 34607942 DOI: 10.1073/pnas.2022523118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2021] [Indexed: 11/18/2022] Open
Abstract
Type 1 diabetes (T1D) results from immune infiltration and destruction of insulin-producing β cells within the pancreatic islets of Langerhans (insulitis). Early diagnosis during presymptomatic T1D would allow for therapeutic intervention prior to substantial β-cell loss at onset. There are limited methods to track the progression of insulitis and β-cell mass decline. During insulitis, the islet microvasculature increases permeability, such that submicron-sized particles can extravasate and accumulate within the islet microenvironment. Ultrasound is a widely deployable and cost-effective clinical imaging modality. However, conventional microbubble contrast agents are restricted to the vasculature. Submicron nanodroplet (ND) phase-change agents can be vaporized into micron-sized bubbles, serving as a microbubble precursor. We tested whether NDs extravasate into the immune-infiltrated islet microenvironment. We performed ultrasound contrast-imaging following ND infusion in nonobese diabetic (NOD) mice and NOD;Rag1ko controls and tracked diabetes development. We measured the biodistribution of fluorescently labeled NDs, with histological analysis of insulitis. Ultrasound contrast signal was elevated in the pancreas of 10-wk-old NOD mice following ND infusion and vaporization but was absent in both the noninfiltrated kidney of NOD mice and the pancreas of Rag1ko controls. High-contrast elevation also correlated with rapid diabetes onset. Elevated contrast was also observed as early as 4 wk, prior to mouse insulin autoantibody detection. In the pancreata of NOD mice, infiltrated islets and nearby exocrine tissue were selectively labeled with fluorescent NDs. Thus, contrast ultrasound imaging with ND phase-change agents can detect insulitis prior to diabetes onset. This will be important for monitoring disease progression, to guide and assess preventative therapeutic interventions for T1D.
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Ultrasound and Photoacoustic Imaging of Laser-Activated Phase-Change Perfluorocarbon Nanodroplets. PHOTONICS 2021. [DOI: 10.3390/photonics8100405] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Laser-activated perfluorocarbon nanodroplets (PFCnDs) are emerging phase-change contrast agents that showed promising potential in ultrasound and photoacoustic (US/PA) imaging. Unlike monophase gaseous microbubbles, PFCnDs shift their state from liquid to gas via optical activation and can provide high US/PA contrast on demand. Depending on the choice of perfluorocarbon core, the vaporization and condensation dynamics of the PFCnDs are controllable. Therefore, these configurable properties of activation and deactivation of PFCnDs are employed to enable various imaging approaches, including contrast-enhanced imaging and super-resolution imaging. In addition, synchronous application of both acoustic and optical pulses showed a promising outcome vaporizing PFCnDs with lower activation thresholds. Furthermore, due to their sub-micrometer size, PFCnDs can be used for molecular imaging of extravascular tissue. PFCnDs can also be an effective therapeutic tool. As PFCnDs can carry therapeutic drugs or other particles, they can be used for drug delivery, as well as photothermal and photodynamic therapies. Blood barrier opening for neurological applications was recently demonstrated with optically-triggered PFCnDs. This paper specifically focuses on the activation and deactivation properties of laser-activated PFCnDs and associated US/PA imaging approaches, and briefly discusses their theranostic potential and future directions.
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Exner AA, Kolios MC. Bursting Microbubbles: How Nanobubble Contrast Agents Can Enable the Future of Medical Ultrasound Molecular Imaging and Image-Guided Therapy. Curr Opin Colloid Interface Sci 2021; 54:101463. [PMID: 34393610 PMCID: PMC8356903 DOI: 10.1016/j.cocis.2021.101463] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The field of medical ultrasound has undergone a significant evolution since the development of microbubbles as contrast agents. However, due to their size, microbubbles remain in the vasculature, and therefore have limited clinical applications. Building a better - and smaller - bubble can expand the applications of contrast-enhanced ultrasound by allowing bubbles to extravasate from blood vessels - creating new opportunities. In this review, we summarize recent research on the formulation and use of NBs as imaging agents and as therapeutic vehicles. We discuss the ongoing debates in the field and reluctance to accepting NBs as an acoustically active construct and a potentially impactful clinical tool that can help shape the future of medical ultrasound. We hope that the overview of key experimental and theoretical findings in the NB field presented in this paper provides a fundamental framework that will help clarify NB-ultrasound interactions and inspire engagement in the field.
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Affiliation(s)
- Agata A. Exner
- Departments of Radiology and Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
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Krafft MP, Riess JG. Therapeutic oxygen delivery by perfluorocarbon-based colloids. Adv Colloid Interface Sci 2021; 294:102407. [PMID: 34120037 DOI: 10.1016/j.cis.2021.102407] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 03/18/2021] [Accepted: 03/25/2021] [Indexed: 02/06/2023]
Abstract
After the protocol-related indecisive clinical trial of Oxygent, a perfluorooctylbromide/phospholipid nanoemulsion, in cardiac surgery, that often unduly assigned the observed untoward effects to the product, the development of perfluorocarbon (PFC)-based O2 nanoemulsions ("blood substitutes") has come to a low. Yet, significant further demonstrations of PFC O2-delivery efficacy have continuously been reported, such as relief of hypoxia after myocardial infarction or stroke; protection of vital organs during surgery; potentiation of O2-dependent cancer therapies, including radio-, photodynamic-, chemo- and immunotherapies; regeneration of damaged nerve, bone or cartilage; preservation of organ grafts destined for transplantation; and control of gas supply in tissue engineering and biotechnological productions. PFC colloids capable of augmenting O2 delivery include primarily injectable PFC nanoemulsions, microbubbles and phase-shift nanoemulsions. Careful selection of PFC and other colloid components is critical. The basics of O2 delivery by PFC nanoemulsions will be briefly reminded. Improved knowledge of O2 delivery mechanisms has been acquired. Advanced, size-adjustable O2-delivering nanoemulsions have been designed that have extended room-temperature shelf-stability. Alternate O2 delivery options are being investigated that rely on injectable PFC-stabilized microbubbles or phase-shift PFC nanoemulsions. The latter combine prolonged circulation in the vasculature, capacity for penetrating tumor tissues, and acute responsiveness to ultrasound and other external stimuli. Progress in microbubble and phase-shift emulsion engineering, control of phase-shift activation (vaporization), understanding and control of bubble/ultrasound/tissue interactions is discussed. Control of the phase-shift event and of microbubble size require utmost attention. Further PFC-based colloidal systems, including polymeric micelles, PFC-loaded organic or inorganic nanoparticles and scaffolds, have been devised that also carry substantial amounts of O2. Local, on-demand O2 delivery can be triggered by external stimuli, including focused ultrasound irradiation or tumor microenvironment. PFC colloid functionalization and targeting can help adjust their properties for specific indications, augment their efficacy, improve safety profiles, and expand the range of their indications. Many new medical and biotechnological applications involving fluorinated colloids are being assessed, including in the clinic. Further uses of PFC-based colloidal nanotherapeutics will be briefly mentioned that concern contrast diagnostic imaging, including molecular imaging and immune cell tracking; controlled delivery of therapeutic energy, as for noninvasive surgical ablation and sonothrombolysis; and delivery of drugs and genes, including across the blood-brain barrier. Even when the fluorinated colloids investigated are designed for other purposes than O2 supply, they will inevitably also carry and deliver a certain amount of O2, and may thus be considered for O2 delivery or co-delivery applications. Conversely, O2-carrying PFC nanoemulsions possess by nature a unique aptitude for 19F MR imaging, and hence, cell tracking, while PFC-stabilized microbubbles are ideal resonators for ultrasound contrast imaging and can undergo precise manipulation and on-demand destruction by ultrasound waves, thereby opening multiple theranostic opportunities.
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Affiliation(s)
- Marie Pierre Krafft
- University of Strasbourg, Institut Charles Sadron (CNRS), 23 rue du Loess, 67034 Strasbourg, France.
| | - Jean G Riess
- Harangoutte Institute, 68160 Ste Croix-aux-Mines, France
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Heymans SV, Carlier B, Toumia Y, Nooijens S, Ingram M, Giammanco A, d'Agostino E, Crijns W, Bertrand A, Paradossi G, Himmelreich U, D'hooge J, Sterpin E, Van Den Abeele K. Modulating ultrasound contrast generation from injectable nanodroplets for proton range verification by varying the degree of superheat. Med Phys 2021; 48:1983-1995. [PMID: 33587754 DOI: 10.1002/mp.14778] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 01/21/2021] [Accepted: 02/08/2021] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Despite the physical benefits of protons over conventional photon radiation in cancer treatment, range uncertainties impede the ability to harness the full potential of proton therapy. While monitoring the proton range in vivo could reduce the currently adopted safety margins, a routinely applicable range verification technique is still lacking. Recently, phase-change nanodroplets were proposed for proton range verification, demonstrating a reproducible relationship between the proton range and generated ultrasound contrast after radiation-induced vaporization at 25°C. In this study, previous findings are extended with proton irradiations at different temperatures, including the physiological temperature of 37°C, for a novel nanodroplet formulation. Moreover, the potential to modulate the linear energy transfer (LET) threshold for vaporization by varying the degree of superheat is investigated, where the aim is to demonstrate vaporization of nanodroplets directly by primary protons. METHODS Perfluorobutane nanodroplets with a shell made of polyvinyl alcohol (PVA-PFB) or 10,12-pentacosadyinoic acid (PCDA-PFB) were dispersed in polyacrylamide hydrogels and irradiated with 62 MeV passively scattered protons at temperatures of 37°C and 50°C. Nanodroplet transition into echogenic microbubbles was assessed using ultrasound imaging (gray value and attenuation analysis) and optical images. The proton range was measured independently and compared to the generated contrast. RESULTS Nanodroplet design proved crucial to ensure thermal stability, as PVA-shelled nanodroplets dramatically outperformed their PCDA-shelled counterpart. At body temperature, a uniform radiation response proximal to the Bragg peak is attributed to nuclear reaction products interacting with PVA-PFB nanodroplets, with the 50% drop in ultrasound contrast being 0.17 mm ± 0.20 mm (mean ± standard deviation) in front of the proton range. Also at 50°C, highly reproducible ultrasound contrast profiles were obtained with shifts of -0.74 mm ± 0.09 mm (gray value analysis), -0.86 mm ± 0.04 mm (attenuation analysis) and -0.64 mm ± 0.29 mm (optical analysis). Moreover, a strong contrast enhancement was observed near the Bragg peak, suggesting that nanodroplets were sensitive to primary protons. CONCLUSIONS By varying the degree of superheat of the nanodroplets' core, one can modulate the intensity of the generated ultrasound contrast. Moreover, a submillimeter reproducible relationship between the ultrasound contrast and the proton range was obtained, either indirectly via the visualization of secondary reaction products or directly through the detection of primary protons, depending on the degree of superheat. The potential of PVA-PFB nanodroplets for in vivo proton range verification was confirmed by observing a reproducible radiation response at physiological temperature, and further studies aim to assess the nanodroplets' performance in a physiological environment. Ultimately, cost-effective online or offline ultrasound imaging of radiation-induced nanodroplet vaporization could facilitate the reduction of safety margins in treatment planning and enable adaptive proton therapy.
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Affiliation(s)
- Sophie V Heymans
- Department of Physics, KU Leuven Campus Kulak, Kortrijk, Belgium
| | - Bram Carlier
- Department of Oncology, KU Leuven, Leuven, Belgium.,Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium
| | - Yosra Toumia
- Department of Chemical Sciences and Technology, University of Rome Tor Vergata, Rome, Italy
| | - Sjoerd Nooijens
- Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - Marcus Ingram
- Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | | | | | | | | | - Gaio Paradossi
- Department of Chemical Sciences and Technology, University of Rome Tor Vergata, Rome, Italy
| | - Uwe Himmelreich
- Molecular Small Animal Imaging Center, KU Leuven, Leuven, Belgium.,Department of Imaging & Pathology, KU Leuven, Leuven, Belgium
| | - Jan D'hooge
- Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
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28
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Loskutova K, Nimander D, Gouwy I, Chen H, Ghorbani M, Svagan AJ, Grishenkov D. A Study on the Acoustic Response of Pickering Perfluoropentane Droplets in Different Media. ACS OMEGA 2021; 6:5670-5678. [PMID: 33681606 PMCID: PMC7931408 DOI: 10.1021/acsomega.0c06115] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 02/12/2021] [Indexed: 06/12/2023]
Abstract
Acoustic droplet vaporization (ADV) is the physical process of liquid-to-gas phase transition mediated by pressure variations in an ultrasound field. In this study, the acoustic response of novel particle-stabilized perfluoropentane droplets was studied in bulk and confined media. The oil/water interface was stabilized by cellulose nanofibers. First, their acoustic responses under idealized conditions were examined to assess their susceptibility to undergo ADV. Second, the droplets were studied in a more realistic setting and placed in a confined medium. Lastly, an imaging setup was developed and tested on the droplets. The acoustic response could be seen when the amplitude of the peak negative pressure (PNP) was above 200 kPa, suggesting that this is the vaporization pressure threshold for these droplets. Increasing the PNP resulted in a decrease in signal intensity over time, suggesting a more destructive behavior. The imaging setup was able to differentiate between the droplets and the surrounding tissue. Results obtained within this study suggest that these droplets have potential in terms of ultrasound-mediated diagnostics and therapy.
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Affiliation(s)
- Ksenia Loskutova
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
| | - Didrik Nimander
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
| | - Isabelle Gouwy
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
| | - Hongjian Chen
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
| | - Morteza Ghorbani
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
- Sabanci
University Nanotechnology Research and Application Center, Istanbul 34956, Turkey
| | - Anna J. Svagan
- Department
of Fibre and Polymer Technology, KTH Royal
Institute of Technology, Stockholm 10044, Sweden
| | - Dmitry Grishenkov
- Department
of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Stockholm 14157, Sweden
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29
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Thomas AN, Song KH, Upadhyay A, Papadopoulou V, Ramirez D, Benninger RKP, Lowerison M, Song P, Murray TW, Borden MA. Contrast-Enhanced Sonography with Biomimetic Lung Surfactant Nanodrops. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:2386-2396. [PMID: 33566623 PMCID: PMC8988746 DOI: 10.1021/acs.langmuir.0c03349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nanodrops comprising a perfluorocarbon liquid core can be acoustically vaporized into echogenic microbubbles for ultrasound imaging. Packaging the microbubble in its condensed liquid state provides some advantages, including in situ activation of the acoustic signal, longer circulation persistence, and the advent of expanded diagnostic and therapeutic applications in pathologies which exhibit compromised vasculature. One obstacle to clinical translation is the inability of the limited surfactant present on the nanodrop to encapsulate the greatly expanded microbubble interface, resulting in ephemeral microbubbles with limited utility. In this study, we examine a biomimetic approach to stabilize an expanding gas surface by employing the lung surfactant replacement, beractant. Lung surfactant contains a suite of lipids and proteins that provide efficient shuttling of material from bilayer folds to the monolayer surface. We hypothesized that beractant would improve stability of acoustically vaporized microbubbles. To test this hypothesis, we characterized beractant surface dilation mechanics and revealed a novel biophysical phenomenon of rapid interfacial melting, spreading, and resolidification. We then harnessed this unique functionality to increase the stability and echogenicity of microbubbles produced after acoustic droplet vaporization for in vivo ultrasound imaging. Such biomimetic lung surfactant-stabilized nanodrops may be useful for applications in ultrasound imaging and therapy.
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Affiliation(s)
- Alec N Thomas
- Department of Mechanical Engineering, University of Colorado, Boulder 80309, Colorado, United States
- Institute of Biomedical Engineering, Oxford University, Oxford OX3 7DQ, U.K
| | - Kang-Ho Song
- Department of Mechanical Engineering, University of Colorado, Boulder 80309, Colorado, United States
| | - Awaneesh Upadhyay
- Department of Mechanical Engineering, University of Colorado, Boulder 80309, Colorado, United States
| | - Virginie Papadopoulou
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill & North Carolina State University, Chapel Hill 27514, North Carolina, United States
| | - David Ramirez
- Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Boulder 80045, Colorado, United States
| | - Richard K P Benninger
- Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Boulder 80045, Colorado, United States
| | - Matthew Lowerison
- Department of Electrical and Computer Engineering, University of Illinois, Urbana-Champaign 61801, Colorado, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign 61801, Colorado, United States
| | - Pengfei Song
- Department of Electrical and Computer Engineering, University of Illinois, Urbana-Champaign 61801, Colorado, United States
- Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign 61801, Colorado, United States
| | - Todd W Murray
- Department of Mechanical Engineering, University of Colorado, Boulder 80309, Colorado, United States
- Department of Biomedical Engineering, University of Colorado, Boulder 80309, Colorado, United States
| | - Mark A Borden
- Department of Mechanical Engineering, University of Colorado, Boulder 80309, Colorado, United States
- Department of Biomedical Engineering, University of Colorado, Boulder 80309, Colorado, United States
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30
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Lawanprasert A, Chau A, Sloand JN, Hannifin S, Medina SH. Tuning the Interfacial Properties of Fluorous Colloids Toward Ultrasound Programmable Bioactivity. ACS APPLIED MATERIALS & INTERFACES 2021; 13:5989-5998. [PMID: 33522791 DOI: 10.1021/acsami.0c20352] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Liquid-in-liquid emulsions are kinetically stable colloids that undergo liquid-to-gas phase transitions in response to thermal or acoustic stimuli. Perfluorocarbons (PFCs) are preferred species as their highly fluorinated nature imparts unique properties that are unparalleled by nonfluorinated counterparts. However, traditional methods to prepare PFC emulsions lack the ability to precisely tune the thermodynamic stability of the fluorous-water interphase and consequently control their vaporization behavior. Here, we report a privileged fluoroalkanoic acid that undergoes concentration-dependent assembly on the surfaces of fluorous droplets to modulate interfacial tension. This allows for the rational formulation of orthogonal PFC droplets that can be programmed to vaporize at specified ultrasound powers. We exploit this behavior in two exemplary biomedical settings by developing emulsions that aid ultrasound-mediated hemostasis and enable bioorthogonal delivery of molecular sensors to mammalian cells. Mechanistic insights gained from these studies can be generalized to tune the thermodynamic interfacial equilibria of PFC emulsions toward designing controllable tools for precision medicine.
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Affiliation(s)
- Atip Lawanprasert
- Department of Biomedical Engineering, Penn State University, University Park, Pennsylvania 16802, United States
| | - Alda Chau
- Department of Biomedical Engineering, Penn State University, University Park, Pennsylvania 16802, United States
| | - Janna N Sloand
- Department of Biomedical Engineering, Penn State University, University Park, Pennsylvania 16802, United States
| | - Sean Hannifin
- Department of Biomedical Engineering, Penn State University, University Park, Pennsylvania 16802, United States
- Immunology Graduate Program, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Scott H Medina
- Department of Biomedical Engineering, Penn State University, University Park, Pennsylvania 16802, United States
- Huck Institutes of the Life Sciences, Penn State University, University Park, Pennsylvania 16802, United States
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32
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Borden MA, Shakya G, Upadhyay A, Song KH. Acoustic Nanodrops for Biomedical Applications. Curr Opin Colloid Interface Sci 2020; 50:101383. [PMID: 33100885 PMCID: PMC7581261 DOI: 10.1016/j.cocis.2020.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Acoustic nanodrops are designed to vaporize into ultrasound-responsive microbubbles, which presents certain challenges nonexistent for conventional nano-emulsions. The requirements of biocompatibility, vaporizability and colloidal stability has focused research on perfluorocarbons (PFCs). Shorter PFCs yield better vaporizability via their lower critical temperature, but they also dissolve more easily owing to their higher vapor pressure and solubility. Thus, acoustic nanodrops have required a tradeoff between vaporizability and colloidal stability in vivo. The recent advent of vaporizable endoskeletal droplets, which are both stable and vaporizable, may have solved this problem. The purpose of this review is to justify this premise by pointing out the beneficial properties of acoustic nanodrops, providing an analysis of vaporization and dissolution mechanisms, and reviewing current biomedical applications.
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Affiliation(s)
- Mark A. Borden
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Gazendra Shakya
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Awaneesh Upadhyay
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
| | - Kang-Ho Song
- Biomedical Engineering, Mechanical Engineering, University of Colorado, Boulder, USA
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33
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Recent Advances on Ultrasound Contrast Agents for Blood-Brain Barrier Opening with Focused Ultrasound. Pharmaceutics 2020; 12:pharmaceutics12111125. [PMID: 33233374 PMCID: PMC7700476 DOI: 10.3390/pharmaceutics12111125] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
The blood-brain barrier is the primary obstacle to efficient intracerebral drug delivery. Focused ultrasound, in conjunction with microbubbles, is a targeted and non-invasive way to disrupt the blood-brain barrier. Many commercially available ultrasound contrast agents and agents specifically designed for therapeutic purposes have been investigated in ultrasound-mediated blood-brain barrier opening studies. The new generation of sono-sensitive agents, such as liquid-core droplets, can also potentially disrupt the blood-brain barrier after their ultrasound-induced vaporization. In this review, we describe the different compositions of agents used for ultrasound-mediated blood-brain barrier opening in recent studies, and we discuss the challenges of the past five years related to the optimal formulation of agents.
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Hoogendijk E, Swider E, Staal AHJ, White PB, van Riessen NK, Glaßer G, Lieberwirth I, Musyanovych A, Serra CA, Srinivas M, Koshkina O. Continuous-Flow Production of Perfluorocarbon-Loaded Polymeric Nanoparticles: From the Bench to Clinic. ACS APPLIED MATERIALS & INTERFACES 2020; 12:49335-49345. [PMID: 33086007 PMCID: PMC7645868 DOI: 10.1021/acsami.0c12020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/08/2020] [Indexed: 05/05/2023]
Abstract
Perfluorocarbon-loaded nanoparticles are powerful theranostic agents, which are used in the therapy of cancer and stroke and as imaging agents for ultrasound and 19F magnetic resonance imaging (MRI). Scaling up the production of perfluorocarbon-loaded nanoparticles is essential for clinical translation. However, it represents a major challenge as perfluorocarbons are hydrophobic and lipophobic. We developed a method for continuous-flow production of perfluorocarbon-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles using a modular microfluidic system, with sufficient yields for clinical use. We combined two slit interdigital micromixers with a sonication flow cell to achieve efficient mixing of three phases: liquid perfluorocarbon, PLGA in organic solvent, and aqueous surfactant solution. The production rate was at least 30 times higher than with the conventional formulation. The characteristics of nanoparticles can be adjusted by changing the flow rates and type of solvent, resulting in a high PFC loading of 20-60 wt % and radii below 200 nm. The nanoparticles are nontoxic, suitable for 19F MRI and ultrasound imaging, and can dissolve oxygen. In vivo 19F MRI with perfluoro-15-crown-5 ether-loaded nanoparticles showed similar biodistribution as nanoparticles made with the conventional method and a fast clearance from the organs. Overall, we developed a continuous, modular method for scaled-up production of perfluorocarbon-loaded nanoparticles that can be potentially adapted for the production of other multiphase systems. Thus, it will facilitate the clinical translation of theranostic agents in the future.
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Affiliation(s)
- Esmee Hoogendijk
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
| | - Edyta Swider
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
| | - Alexander H. J. Staal
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
| | - Paul B. White
- Institute for Molecules and Materials, Radboud University, 6525
AJ Nijmegen, The Netherlands
| | - N. Koen van Riessen
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
| | - Gunnar Glaßer
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ingo Lieberwirth
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | | | - Christophe A. Serra
- Université de Strasbourg,
CNRS, Institut Charles Sadron, 23 rue du Loess, F-67000 Strasbourg, France
| | - Mangala Srinivas
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
| | - Olga Koshkina
- Department of Tumor
Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 26/28, 6525GA Nijmegen, The Netherlands
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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35
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Boerner P, Nevozhay D, Hatamimoslehabadi M, Chawla HS, Zvietcovich F, Aglyamov S, Larin KV, Sokolov KV. Repetitive optical coherence elastography measurements with blinking nanobombs. BIOMEDICAL OPTICS EXPRESS 2020; 11:6659-6673. [PMID: 33282515 PMCID: PMC7687956 DOI: 10.1364/boe.401734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/19/2020] [Accepted: 10/06/2020] [Indexed: 05/04/2023]
Abstract
Excitation of dye-loaded perfluorocarbon nanoparticles (nanobombs) can generate highly localized axially propagating longitudinal shear waves (LSW) that can be used to quantify tissue mechanical properties without transversal scanning of the imaging beam. In this study, we used repetitive excitations of dodecafluoropentane (C5) and tetradecafluorohexane (C6) nanobombs by a nanosecond-pulsed laser to produce multiple LSWs from a single spot in a phantom. A 1.5 MHz Fourier-domain mode-locked laser in combination with a phase correction algorithm was used to perform elastography. Multiple nanobomb activations were also monitored by detecting photoacoustic signals. Our results demonstrate that C6 nanobombs can be used for repetitive generation of LSW from a single spot for the purpose of material elasticity assessment. This study opens new avenues for continuous quantification of tissue mechanical properties using single delivery of the nanoparticles.
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Affiliation(s)
- Paul Boerner
- Department of Biomedical Engineering, University of Houston, Houston, Texas 77204, USA
- Equal contribution
| | - Dmitry Nevozhay
- Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
- Equal contribution
| | | | | | - Fernando Zvietcovich
- Department of Biomedical Engineering, University of Houston, Houston, Texas 77204, USA
| | - Salavat Aglyamov
- Department of Mechanical Engineering, University of Houston, Houston, Texas 77204, USA
| | - Kirill V Larin
- Department of Biomedical Engineering, University of Houston, Houston, Texas 77204, USA
| | - Konstantin V Sokolov
- Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA
- Department of Bioengineering, Rice University, Houston, Texas 77030, USA
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W Dean Keeton Street, Austin, Texas 78712, USA
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Sjöstrand S, Evertsson M, Jansson T. Magnetomotive Ultrasound Imaging Systems: Basic Principles and First Applications. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:2636-2650. [PMID: 32753288 DOI: 10.1016/j.ultrasmedbio.2020.06.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 04/29/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
This review discusses magnetomotive ultrasound, which is an emerging technique that uses superparamagnetic iron oxide nanoparticles as a contrast agent. The key advantage of using nanoparticle-based contrast agents is their ability to reach extravascular targets, whereas commercial contrast agents for ultrasound comprise microbubbles confined to the blood stream. This also extends possibilities for molecular imaging, where the contrast agent is labeled with specific targeting molecules (e.g., antibodies) so that pathologic tissue may be visualized directly. The principle of action is that an external time-varying magnetic field acts to displace the nanoparticles lodged in tissue and thereby their immediate surrounding. This movement is then detected with ultrasound using frequency- or time-domain analysis of echo data. As a contrast agent already approved for magnetic resonance imaging (MRI) by the US Food and Drug Administration, there is a shorter path to clinical translation, although safety studies of magnetomotion are necessary, especially if particle design is altered to affect biodistribution or signal strength. The external modulated magnetic field may be generated by electromagnets, permanent magnets, or a combination of the two. The induced nanoparticle motion may also reveal mechanical material properties of tissue, healthy or diseased, one of several interesting potential future aspects of the technique.
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Affiliation(s)
- Sandra Sjöstrand
- Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Maria Evertsson
- Department of Clinical Sciences Lund/Biomedical Engineering, Lund University, Lund, Sweden
| | - Tomas Jansson
- Department of Clinical Sciences Lund/Biomedical Engineering, Lund University, Lund, Sweden; Clinical Engineering Skåne, Digitalisering IT/MT, Region Skåne, Lund, Sweden.
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Pellow C, Abenojar EC, Exner AA, Zheng G, Goertz DE. Concurrent visual and acoustic tracking of passive and active delivery of nanobubbles to tumors. Am J Cancer Res 2020; 10:11690-11706. [PMID: 33052241 PMCID: PMC7545999 DOI: 10.7150/thno.51316] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/10/2020] [Indexed: 02/06/2023] Open
Abstract
Background: There has been growing interest in nanobubbles for their potential to extend bubble-mediated ultrasound approaches beyond that of their larger microbubble counterparts. In particular, the smaller scale of nanobubbles may enable them to access the tumor extravascular compartment for imaging and therapy in closer proximity to cancer cells. Compelling preliminary demonstrations of the imaging and therapeutic abilities of nanobubbles have thus emerged, with emphasis on their ability to extravasate. However, studies to date rely on indirect histologic evidence that cannot confirm whether the structures remain intact beyond the vasculature - leaving their extravascular potential largely untapped. Methods: Nanobubble acoustic scattering was assessed using a recently reported ultra-stable formulation at low concentration (106 mL-1) and frequency (1 MHz), over a range of pressures (100-1500 kPa) in a channel phantom. The pressure-dependent response was utilized as a basis for in vivo experiments where ultrasound transmitters and receivers were integrated into a window chamber for simultaneous intravital multiphoton microscopy and acoustic monitoring in tumor-affected microcirculation. Microscopy and acoustic data were utilized to assess passive and active delivery of nanobubbles and determine whether they remained intact beyond the vasculature. Results: Nanobubbles exhibit pressure-dependent nonlinear acoustic scattering. Nanobubbles are also found to have prolonged acoustic vascular pharmacokinetics, and passively extravasate intact into tumors. Ultrasound stimulation of nanobubbles is shown to actively enhance the delivery of both intact nanobubbles and shell material, increasing their spatial bioavailability deeper into the extravascular space. A range of acute vascular effects were also observed. Conclusion: This study presents the first direct evidence that nanobubbles passively and actively extravasate intact in tumor tissue, and is the first to directly capture acute vascular events from ultrasound-stimulation of nanobubbles. The insights gained here demonstrate an important step towards unlocking the potential of nanobubbles and extending ultrasound-based applications.
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Melich R, Zorgani A, Padilla F, Charcosset C. Preparation of perfluorocarbon emulsions by premix membrane emulsification for Acoustic Droplet Vaporization (ADV) in biomedical applications. Biomed Microdevices 2020; 22:62. [PMID: 32880712 DOI: 10.1007/s10544-020-00504-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Perfluorocarbon (PFC) droplets are used in acoustic droplet vaporization (ADV), a phenomenon where droplets vaporize into gas microbubbles under exposure to ultrasound. The size and the size distribution of a phase change contrast agent is an important factor in determining the ADV threshold and the biodistribution. Thus, high throughout manufacturing of uniform-sized droplets, required to maintain spatial control of the vaporization process, remains challenging. This work describes a parametric evaluation of a novel process using premix membrane emulsification (PME) to produce homogeneous PFC emulsions at high rate with moderate pressure using Shirasu Porous Glass (SPG) membranes. In this study, we investigated the effect of several process parameters on the resulting pressure and droplet size: membrane pore size, flow rate, and dispersed phase type. The functionality of the manufactured emulsions for ADV was also demonstrated. Vaporization of the PFC emulsions was obtained using an imaging ultrasound transducer at 7.813 MHz, and the ADV thresholds were determined. Here, the pressure threshold for ADV was determined to be 1.49 MPa for uniform-sized perfluorohexane (PFHex) droplets with a mean size of 1.51 μm and a sharp distribution (CV and span respectively of 20% and 0.6). Thus, a uniform-sized droplet showed a more homogeneous vaporization with a uniform response in the focal region of the transducer. Indeed, polydispersed droplets had a more diffuse response outside the focal region due to the presence of large droplets that vaporize at lower energies. The ADV threshold of uniform-sized PFC droplets was found to decrease with the droplet diameter and the bulk fluid temperature, and to increase with the boiling temperature of PFC and the presence of an oil layer surrounding the PFC core.
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Affiliation(s)
- Romain Melich
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, LAGEPP UMR 5007, 43 boulevard du 11 novembre 1918, F-69100, Villeurbanne, France
- LabTAU, INSERM, Centre Léon Bérard, Université Lyon 1, Univ-Lyon, F-69003, LYON, France
| | - Ali Zorgani
- LabTAU, INSERM, Centre Léon Bérard, Université Lyon 1, Univ-Lyon, F-69003, LYON, France
| | - Frédéric Padilla
- LabTAU, INSERM, Centre Léon Bérard, Université Lyon 1, Univ-Lyon, F-69003, LYON, France.
- Department of Radiology, University of Virginia School of Medicine, Charlottesville, VA, USA.
- Focused Ultrasound Foundation, 1230 Cedars Court, Suite 206, Charlottesville, VA, USA.
| | - Catherine Charcosset
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, LAGEPP UMR 5007, 43 boulevard du 11 novembre 1918, F-69100, Villeurbanne, France.
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Melich R, Bussat P, Morici L, Vivien A, Gaud E, Bettinger T, Cherkaoui S. Microfluidic preparation of various perfluorocarbon nanodroplets: Characterization and determination of acoustic droplet vaporization (ADV) threshold. Int J Pharm 2020; 587:119651. [DOI: 10.1016/j.ijpharm.2020.119651] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 12/16/2022]
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Jing B, Kashyap EP, Lindsey BD. Transcranial activation and imaging of low boiling point phase-change contrast agents through the temporal bone using an ultrafast interframe activation ultrasound sequence. Med Phys 2020; 47:4450-4464. [PMID: 32657429 DOI: 10.1002/mp.14390] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/08/2020] [Accepted: 07/07/2020] [Indexed: 12/14/2022] Open
Abstract
PURPOSE As a cavitation enhancer, low boiling point phase-change contrast agents (PCCA) offer potential for ultrasound-mediated drug delivery in applications including intracerebral hemorrhage or brain tumors. In addition to introducing cavitation, ultrasound imaging also has the ability to provide guidance and monitoring of the therapeutic process by localizing delivery events. However, the highly attenuating skull poses a challenge for achieving an image with useful contrast. In this study, the feasibility of transcranial activation and imaging of low boiling point PCCAs through the human temporal bone was investigated by using a low frequency ultrafast interframe activation ultrasound (UIAU) imaging sequence with singular value decomposition-based denoising. METHODS Lipid-shelled PCCAs filled with decafluorobutane were activated and imaged at 37°C in tissue-mimicking phantoms both without and with an ex vivo human skull using the new UIAU sequence and a low frequency diagnostic transducer array at frequencies from 1.5 to 3.5 MHz. A singular value decomposition-based denoising filter was developed and used to further enhance transcranial image contrast. The contrast-to-tissue ratio (CTR) and contrast enhancement (CE) of UIAU was quantitatively evaluated and compared with the amplitude modulation pulse inversion (AMPI) and vaporization detection imaging (VDI) approaches. RESULTS Image results demonstrate enhanced contrast in the phantom channel with suppressed background when the low boiling point PCCA was activated both without and with an ex vivo human skull using the UIAU sequence. Quantitative results show that without the skull, low frequency UIAU imaging provided significantly higher image contrast (CTR ≥ 18.56 dB and CE ≥ 18.66 dB) than that of AMPI and VDI (P < 0.05). Transcranial imaging results indicated that the CE of UIAU (≥18.80 dB) was significantly higher than AMPI for free-field activation pressures of 5 and 6 MPa. The CE of UIAU is also significantly higher than that of VDI when PCCAs were activated at 2.5 MHz and 3 MHz (P < 0.05). The CTR (23.30 [20.07-25.56] dB) of denoised UIAU increased by 12.58 dB relative to the non-denoised case and was significantly higher than that of AMPI at an activation pressure of 4 MPa (P < 0.05). CONCLUSIONS Results indicate that low boiling point PCCAs can be activated and imaged at low frequencies including imaging through the temporal bone using the UIAU sequence. The UIAU imaging approach provides higher contrast than AMPI and VDI, especially at lower activation pressures with additional removal of electronic noise.
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Affiliation(s)
- Bowen Jing
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
| | - Esha P Kashyap
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA
| | - Brooks D Lindsey
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30332, USA.,School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
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Carlier B, Heymans SV, Nooijens S, Toumia Y, Ingram M, Paradossi G, D’Agostino E, Himmelreich U, D’hooge J, Van Den Abeele K, Sterpin E. Proton range verification with ultrasound imaging using injectable radiation sensitive nanodroplets: a feasibility study. ACTA ACUST UNITED AC 2020; 65:065013. [DOI: 10.1088/1361-6560/ab7506] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Mercado-Shekhar KP, Su H, Kalaikadal DS, Lorenz JN, Manglik RM, Holland CK, Redington AN, Haworth KJ. Acoustic droplet vaporization-mediated dissolved oxygen scavenging in blood-mimicking fluids, plasma, and blood. ULTRASONICS SONOCHEMISTRY 2019; 56:114-124. [PMID: 31101245 PMCID: PMC6659737 DOI: 10.1016/j.ultsonch.2019.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/20/2018] [Accepted: 03/27/2019] [Indexed: 05/20/2023]
Abstract
Acoustic droplet vaporization (ADV) has been shown to reduce the partial pressure of oxygen (PO2) in a fluid. The goals of this study were three-fold: 1) to determine the ADV pressure amplitude threshold in fluids that had physiologically relevant values for surface tension, protein concentration, and viscosity; 2) to assess whether these parameters and fluid mixing affect ADV-mediated PO2 reduction; and 3) to assess the feasibility of ADV-mediated PO2 reduction in plasma and whole blood. In vitro ADV experiments were conducted using perfluoropentane droplets (number density: 5 × 106 ± 0.2 × 106/mL) dispersed in fluids (saline, polyvinylpyrrolidone solutions, porcine plasma, or porcine whole blood) that had a physiological range of surface tensions (62-68 mN/m), protein concentrations (0 and 68.7 mg/mL), and viscosities (0.7-4 cP). Droplets were exposed to pulsed ultrasound (5 MHz, 4.25 MPa peak negative pressure) while passing through a 37 °C flow system with inline PO2 sensors. In select experiments, the fluid also passed through mixing channels after ultrasound exposure. Our results revealed that the ADV pressure thresholds were the same for all fluids. Surface tension and protein concentration had no effect on PO2 reduction. Increasing viscosity attenuated PO2 reduction. However, the attenuated effect was absent after fluid mixing. Furthermore, ADV-mediated PO2 reduction in whole blood (30.8 ± 3.2 mmHg) was less than that in a polyvinylpyrrolidone solution (40.2 ± 2.1 mmHg) with equal viscosity. These findings should be considered when planning clinical studies of ADV-mediated PO2 reduction and other biomedical applications of ADV.
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Affiliation(s)
| | - Haili Su
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, USA
| | - Deepak S Kalaikadal
- Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, OH, USA
| | - John N Lorenz
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, USA
| | - Raj M Manglik
- Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, OH, USA
| | - Christy K Holland
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA
| | - Andrew N Redington
- Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Kevin J Haworth
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA; Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
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Toumia Y, Cerroni B, Domenici F, Lange H, Bianchi L, Cociorb M, Brasili F, Chiessi E, D'Agostino E, Van Den Abeele K, Heymans SV, D'Hooge J, Paradossi G. Phase Change Ultrasound Contrast Agents with a Photopolymerized Diacetylene Shell. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:10116-10127. [PMID: 31042396 DOI: 10.1021/acs.langmuir.9b01160] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Phase change contrast agents for ultrasound (US) imaging consist of nanodroplets (NDs) with a perfluorocarbon (PFC) liquid core stabilized with a lipid or a polymer shell. Liquid ↔ gas transition, occurring in the core, can be triggered by US to produce acoustically active microbubbles (MBs) in a process named acoustic droplet vaporization (ADV). MB shells containing polymerized diacetylene moiety were considered as a good trade off between the lipid MBs, showing optimal attenuation, and the polymeric ones, displaying enhanced stability. This work reports on novel perfluoropentane and perfluorobutane NDs stabilized with a monolayer of an amphiphilic fatty acid, i.e. 10,12-pentacosadiynoic acid (PCDA), cured with ultraviolet (UV) irradiation. The photopolymerization of the diacetylene groups, evidenced by the appearance of a blue color due to the conjugation of ene-yne sequences, exhibits a chromatic transition from the nonfluorescent blue color to a fluorescent red color when the NDs are heated or the pH of the suspension is basic. An estimate of the molecular weights reached by the polymerized PCDA in the shell, poly(PCDA), has been obtained using gel permeation chromatography and MALDI-TOF mass spectrometry. The poly(PCDA)/PFC NDs show good biocompatibility with fibroblast cells. ADV efficiency and acoustic properties before and after the transition were tested using a 1 MHz probe, revealing a resonance frequency between 1 and 2 MHz similar to other lipidic MBs. The surface of PCDA shelled NDs can be easily modified without influencing the stability and the acoustic performances of droplets. As a proof of concept we report on the conjugation of cyclic RGD and PEG chains of the particles to support targeting ability toward endothelial cells.
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Affiliation(s)
- Yosra Toumia
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Barbara Cerroni
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Fabio Domenici
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Heiko Lange
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Livia Bianchi
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Madalina Cociorb
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Francesco Brasili
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Ester Chiessi
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
| | - Emiliano D'Agostino
- DoseVue NV , Philips Open Manufacturing Campus , Slachthuisstraat 96 , B-2300 Turnhout , Belgium
| | | | - Sophie V Heymans
- Department of Physics , KU Leuven , Kulak, 8500 Kortrijk , Belgium
| | - Jan D'Hooge
- Medical Center , KU Leuven , 3000 Leuven , Belgium
| | - Gaio Paradossi
- Department of Chemical Sciences and Technologies , University of Rome Tor Vergata , Via della Ricerca Scientifica 1 , 00133 , Rome , Italy
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Loskutova K, Grishenkov D, Ghorbani M. Review on Acoustic Droplet Vaporization in Ultrasound Diagnostics and Therapeutics. BIOMED RESEARCH INTERNATIONAL 2019; 2019:9480193. [PMID: 31392217 PMCID: PMC6662494 DOI: 10.1155/2019/9480193] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/10/2019] [Accepted: 06/20/2019] [Indexed: 02/06/2023]
Abstract
Acoustic droplet vaporization (ADV) is the physical process in which liquid undergoes phase transition to gas after exposure to a pressure amplitude above a certain threshold. In recent years, new techniques in ultrasound diagnostics and therapeutics have been developed which utilize microformulations with various physical and chemical properties. The purpose of this review is to give the reader a general idea on how ADV can be implemented for the existing biomedical applications of droplet vaporization. In this regard, the recent developments in ultrasound therapy which shed light on the ADV are considered. Modern designs of capsules and nanodroplets (NDs) are shown, and the material choices and their implications for function are discussed. The influence of the physical properties of the induced acoustic field, the surrounding medium, and thermophysical effects on the vaporization are presented. Lastly, current challenges and potential future applications towards the implementation of the therapeutic droplets are discussed.
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Affiliation(s)
- Ksenia Loskutova
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, SE-141 57 Huddinge, Sweden
| | - Dmitry Grishenkov
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, SE-141 57 Huddinge, Sweden
| | - Morteza Ghorbani
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, SE-141 57 Huddinge, Sweden
- Mechatronics Engineering Program, Faculty of Engineering and Natural Science, Sabanci University, Istanbul 34956, Turkey
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Hallam KA, Emelianov SY. Toward optimization of blood brain barrier opening induced by laser-activated perfluorocarbon nanodroplets. BIOMEDICAL OPTICS EXPRESS 2019; 10:3139-3151. [PMID: 31360596 PMCID: PMC6640833 DOI: 10.1364/boe.10.003139] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/30/2019] [Accepted: 05/30/2019] [Indexed: 05/09/2023]
Abstract
The blood brain barrier (BBB), a component of the brain's natural defense system, is often a roadblock for the monitoring and treatment of neurological disorders. Recently, we introduced a technique to open the blood brain barrier through the use of laser-activated perfluorohexane nanodroplets (PFHnDs), a phase-change nanoagent that undergoes repeated vaporization and recondensation when excited by a pulsed laser. Laser-activated PFHnDs were shown to enable noninvasive and localized opening of the BBB, allowing extravasation of various sized agents into the brain tissue. In this current work, the laser-activated PFHnD-induced BBB opening is further explored. In particular, laser fluence and the number of laser pulses used for the PFHnD-induced BBB opening are examined and evaluated both qualitatively and quantitatively to determine the effect of these parameters on BBB opening. The results of these studies show trends between increased laser fluence and an increased BBB opening as well as between an increased number of laser pulses and an increased BBB opening, however, with limitations on the extent of the BBB opening after a certain number of pulses. Overall, the results of these studies serve as a guideline to choosing suitable laser parameters for safe and effective BBB opening.
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Affiliation(s)
- Kristina A. Hallam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Stanislav Y. Emelianov
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, GA, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA, USA
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Synchronized Optical and Acoustic Droplet Vaporization for Effective Sonoporation. Pharmaceutics 2019; 11:pharmaceutics11060279. [PMID: 31197090 PMCID: PMC6631315 DOI: 10.3390/pharmaceutics11060279] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/09/2019] [Accepted: 06/11/2019] [Indexed: 01/05/2023] Open
Abstract
Inertial cavitation-based sonoporation has been utilized to enhance treatment delivery efficacy. In our previous study, we demonstrated that tumor therapeutic efficacy can be enhanced through vaporization-assisted sonoporation with gold nanodroplets (AuNDs). Specifically, the AuNDs were vaporized both acoustically (i.e., acoustic droplet vaporization, ADV) and optically (i.e., optical droplet vaporization, ODV). A continuous wave (CW) laser was used for ODV in combination with an ultrasound pulse for ADV. Although effective for vaporization, the use of a CW laser is not energy efficient and may create unwanted heating and concomitant tissue damage. In this study, we propose the use of a pulsed wave (PW) laser to replace the CW laser. In addition, the PW laser was applied at the rarefaction phase of the ultrasound pulse so that the synergistic effects of ADV and ODV can be expected. Therefore, a significantly lower laser average power can be expected to achieve the vaporization threshold. Compared to the CW laser power at 2 W/cm2 from the previous approach, the PW laser power was reduced to only 0.2404 W/cm2. Furthermore, we also demonstrate in vitro that the sonoporation rate was increased when the PW laser was applied at the rarefaction phase. Specifically, the vaporization signal, the inertial cavitation signal, and the sonoporation rate all displayed a 1-µs period, which corresponded to the period of the 1-MHz acoustic wave used for ADV, as a function of the relative laser delay. The increased sonoporation rate indicates that this technique has the potential to enhance sonoporation-directed drug delivery and tumor therapy with a lower laser power while keeping the cell death rate at the minimum. Photoacoustic imaging can also be performed at the same time since a PW laser is used for the ODV.
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Zhang G, Lin S, Leow CH, Pang KT, Hernández-Gil J, Long NJ, Eckersley R, Matsunaga T, Tang MX. Quantification of Vaporised Targeted Nanodroplets Using High-Frame-Rate Ultrasound and Optics. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:1131-1142. [PMID: 30827708 DOI: 10.1016/j.ultrasmedbio.2019.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/08/2019] [Accepted: 01/11/2019] [Indexed: 06/09/2023]
Abstract
Molecular targeted nanodroplets that can extravasate beyond the vascular space have great potential to improve tumor detection and characterisation. High-frame-rate ultrasound, on the other hand, is an emerging tool for imaging at a frame rate one to two orders of magnitude higher than those of existing ultrasound systems. In this study, we used high-frame-rate ultrasound combined with optics to study the acoustic response and size distribution of folate receptor (FR)-targeted versus non-targeted (NT)-nanodroplets in vitro with MDA-MB-231 breast cancer cells immediately after ultrasound activation. A flow velocity mapping technique, Stokes' theory and optical microscopy were used to estimate the size of both floating and attached vaporised nanodroplets immediately after activation. The floating vaporised nanodroplets were on average more than seven times larger than vaporised nanodroplets attached to the cells. The results also indicated that the acoustic signal of vaporised FR-targeted-nanodroplets persisted after activation, with 70% of the acoustic signals still present 1 s after activation, compared with the vaporised NT-nanodroplets, for which only 40% of the acoustic signal remained. The optical microscopic images revealed on average six times more vaporised FR-targeted-nanodroplets generated with a wider range of diameters (from 4 to 68 µm) that were still attached to the cells, compared with vaporised NT-nanodroplets (from 1 to 7 µm) with non-specific binding after activation. The mean size of attached vaporised FR-targeted-nanodroplets was on average about threefold larger than that of attached vaporised NT-nanodroplets. Taking advantage of high-frame-rate contrast-enhanced ultrasound and optical microscopy, this study offers an improved understanding of the vaporisation of the targeted nanodroplets in terms of their size and acoustic response in comparison with NT-nanodroplets. Such understanding would help in the design of optimised methodology for imaging and therapeutic applications.
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Affiliation(s)
- Ge Zhang
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Shengtao Lin
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Chee Hao Leow
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Kuin Tian Pang
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore
| | | | - Nicholas J Long
- Department of Chemistry, Imperial College London, London, United Kingdom
| | - Robert Eckersley
- Division of Imaging Sciences & Biomedical Engineering Department, King's College London, United Kingdom
| | - Terry Matsunaga
- Department of Medical Imaging, University of Arizona, Tucson, Arizona, USA
| | - Meng-Xing Tang
- Department of Bioengineering, Imperial College London, London, United Kingdom.
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Martin AL, Homenick CM, Xiang Y, Gillies E, Matsuura N. Polyelectrolyte Coatings Can Control Charged Fluorocarbon Nanodroplet Stability and Their Interaction with Macrophage Cells. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4603-4612. [PMID: 30757902 DOI: 10.1021/acs.langmuir.8b04051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fluorocarbon nanodroplets, ∼100 to ∼400 nm in diameter, are of immense interest in a variety of medical applications including the imaging and therapy of cancer and inflammatory diseases. However, fluorocarbon molecules are both hydrophobic and lipophobic; therefore, it is challenging to synthesize fluorocarbon nanodroplets with the optimal stability and surface properties without the use of highly specialized surfactants. Here, we hypothesize that we can decouple the control of fluorocarbon nanodroplet size and stability from its surface properties. We use a simple, two-step procedure where standard, easily available anionic fluorosurfactants are used to first stabilize the fluorocarbon nanodroplets, followed by electrostatically attaching functionalized polyelectrolytes to the nanodroplet surfaces to independently control their surface properties. Herein, we demonstrate that PEGylated polyelectrolyte coatings can effectively alter the fluorocarbon nanodroplet surface properties to reduce coalescence and its uptake into phagocytic cells in comparison with non-PEGylated polyelectrolyte coatings and uncoated nanodroplets, as measured by flow cytometry and fluorescence microscopy. In this study, perfluorooctyl bromide (PFOB) was used as a representative fluorocarbon material, and PEGylated PFOB nanodroplets with diameters between 250 and 290 nm, depending on the poly(ethylene glycol) block length, were prepared. The PEGylated PFOB nanodroplets had superior size stability in comparison with uncoated and non-PEGylated polyelectrolyte nanodroplets in saline and within macrophage cells. Of significance, non-PEGylated nanodroplets were rapidly internalized by macrophage cells, whereas PEGylated nanodroplets were predominantly colocalized on the cell membrane. This suggests that the PEGylated-polyelectrolyte coating on the charged PFOB nanodroplets may afford adjustable shielding from cells of the reticuloendothelial system. This report shows that using the same fluorosurfactant as a base layer, modularly assembled PFOB nanodroplets tailored for a variety of end applications can be created by selecting different polyelectrolyte coatings depending on their unique requirements for stability and interaction with phagocytic cells.
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Affiliation(s)
- Amanda L Martin
- Physical Sciences , Sunnybrook Research Institute , Toronto , Ontario M4N 3M5 , Canada
| | - Christa M Homenick
- Department of Chemistry and Department of Chemical and Biochemical Engineering , The University of Western Ontario , London , Ontario N6A 5B7 , Canada
| | | | - Elizabeth Gillies
- Department of Chemistry and Department of Chemical and Biochemical Engineering , The University of Western Ontario , London , Ontario N6A 5B7 , Canada
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Xiang Y, Bernards N, Hoang B, Zheng J, Matsuura N. Perfluorocarbon nanodroplets can reoxygenate hypoxic tumors in vivo without carbogen breathing. Nanotheranostics 2019; 3:135-144. [PMID: 31008022 PMCID: PMC6470341 DOI: 10.7150/ntno.29908] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 02/08/2019] [Indexed: 12/15/2022] Open
Abstract
Nanoscale perfluorocarbon (PFC) droplets have enormous potential as clinical theranostic agents. They are biocompatible and are currently used in vivo as contrast agents for a variety of medical imaging modalities, including ultrasound, computed tomography, photoacoustic and 19F-magnetic resonance imaging. PFC nanodroplets can also carry molecular and nanoparticulate drugs and be activated in situ by ultrasound or light for targeted therapy. Recently, there has been renewed interest in using PFC nanodroplets for hypoxic tumor reoxygenation towards radiosensitization based on the high oxygen solubility of PFCs. Previous studies showed that tumor oxygenation using PFC agents only occurs in combination with enhanced oxygen breathing. However, recent studies suggest that PFC agents that accumulate in solid tumors can contribute to radiosensitization, presumably due to tumor reoxygenation without enhanced oxygen breathing. In this study, we quantify the impact of oxygenation due to PFC nanodroplet accumulation in tumors alone in comparison with other reoxygenation methodologies, in particular, carbogen breathing. Methods: Lipid-stabilized, PFC (i.e., perfluorooctyl bromide, CF3(CF2)7Br, PFOB) nanoscale droplets were synthesized and evaluated in xenograft prostate (DU145) tumors in male mice. Biodistribution assessment of the nanodroplets was achieved using a fluorescent lipophilic indocarbocyanine dye label (i.e., DiI dye) on the lipid shell in combination with fluorescence imaging in mice (n≥3 per group). Hypoxia reduction in tumors was measured using PET imaging and a known hypoxia radiotracer, [18F]FAZA (n≥ 3 per group). Results: Lipid-stabilized nanoscale PFOB emulsions (mean diameter of ~250 nm), accumulated in the xenograft prostate tumors in mice 24 hours post-injection. In vivo PET imaging with [18F]FAZA showed that the accumulation of the PFOB nanodroplets in the tumor tissues alone significantly reduced tumor hypoxia, without enhanced oxygen (i.e., carbogen) breathing. This reoxygenation effect was found to be comparable with carbogen breathing alone. Conclusion: Accumulation of nanoscale PFOB agents in solid tumors alone successfully reoxygenated hypoxic tumors to levels comparable with carbogen breathing alone, an established tumor oxygenation method. This study confirms that PFC agents can be used to reoxygenate hypoxic tumors in addition to their current applications as multifunctional theranostic agents.
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Affiliation(s)
- Yun Xiang
- Department of Medical Imaging, University of Toronto, Ontario, Canada
| | - Nicholas Bernards
- TECHNA Institute for the Advancement of Technology for Health, University Health Network, Toronto, Ontario, Canada
| | - Bryan Hoang
- Department of Medical Imaging, University of Toronto, Ontario, Canada
- TECHNA Institute for the Advancement of Technology for Health, University Health Network, Toronto, Ontario, Canada
| | - Jinzi Zheng
- TECHNA Institute for the Advancement of Technology for Health, University Health Network, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada
| | - Naomi Matsuura
- Department of Medical Imaging, University of Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada
- Department of Materials Science and Engineering, University of Toronto, Ontario, Canada
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