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Shakya G, Cattaneo M, Guerriero G, Prasanna A, Fiorini S, Supponen O. Ultrasound-responsive microbubbles and nanodroplets: A pathway to targeted drug delivery. Adv Drug Deliv Rev 2024; 206:115178. [PMID: 38199257 DOI: 10.1016/j.addr.2023.115178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/21/2023] [Accepted: 12/31/2023] [Indexed: 01/12/2024]
Abstract
Ultrasound-responsive agents have shown great potential as targeted drug delivery agents, effectively augmenting cell permeability and facilitating drug absorption. This review focuses on two specific agents, microbubbles and nanodroplets, and provides a sequential overview of their drug delivery process. Particular emphasis is given to the mechanical response of the agents under ultrasound, and the subsequent physical and biological effects on the cells. Finally, the state-of-the-art in their pre-clinical and clinical implementation are discussed. Throughout the review, major challenges that need to be overcome in order to accelerate their clinical translation are highlighted.
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Affiliation(s)
- Gazendra Shakya
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Marco Cattaneo
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Giulia Guerriero
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Anunay Prasanna
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Samuele Fiorini
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland
| | - Outi Supponen
- Institute of Fluid Dynamics, D-MAVT, Sonneggstrasse 3, ETH Zurich, Zurich, 8092, Switzerland.
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2
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Aliabouzar M, Kripfgans OD, Brian Fowlkes J, Fabiilli ML. Bubble nucleation and dynamics in acoustic droplet vaporization: a review of concepts, applications, and new directions. Z Med Phys 2023; 33:387-406. [PMID: 36775778 PMCID: PMC10517405 DOI: 10.1016/j.zemedi.2023.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 12/30/2022] [Accepted: 01/09/2023] [Indexed: 02/12/2023]
Abstract
The development of phase-shift droplets has broadened the scope of ultrasound-based biomedical applications. When subjected to sufficient acoustic pressures, the perfluorocarbon phase in phase-shift droplets undergoes a phase-transition to a gaseous state. This phenomenon, termed acoustic droplet vaporization (ADV), has been the subject of substantial research over the last two decades with great progress made in design of phase-shift droplets, fundamental physics of bubble nucleation and dynamics, and applications. Here, we review experimental approaches, carried out via high-speed microscopy, as well as theoretical models that have been proposed to study the fundamental physics of ADV including vapor nucleation and ADV-induced bubble dynamics. In addition, we highlight new developments of ADV in tissue regeneration, which is a relatively recently exploited application. We conclude this review with future opportunities of ADV for advanced applications such as in situ microrheology and pressure estimation.
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Affiliation(s)
- Mitra Aliabouzar
- Department of Radiology, University of Michigan, Ann Arbor, MI, USA; Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
| | - Oliver D Kripfgans
- Department of Radiology, University of Michigan, Ann Arbor, MI, USA; Applied Physics Program, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - J Brian Fowlkes
- Department of Radiology, University of Michigan, Ann Arbor, MI, USA; Applied Physics Program, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Mario L Fabiilli
- Department of Radiology, University of Michigan, Ann Arbor, MI, USA; Applied Physics Program, University of Michigan, Ann Arbor, MI, USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
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3
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Alcaraz PE, Davidson SJ, Shreeve E, Meuschke R, Romanowski M, Witte RS, Porter TR, Matsunaga TO. Thermal and Acoustic Stabilization Of Volatile Phase-Change Contrast Agents Via Layer-By-Layer Assembly. ULTRASOUND IN MEDICINE & BIOLOGY 2023; 49:1058-1069. [PMID: 36797095 PMCID: PMC10050125 DOI: 10.1016/j.ultrasmedbio.2022.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 05/11/2023]
Abstract
OBJECTIVE Phase-change contrast agents (PCCAs) are perfluorocarbon nanodroplets (NDs) that have been widely studied for ultrasound imaging in vitro, pre-clinical studies, and most recently incorporated a variant of PCCAs, namely a microbubble-conjugated microdroplet emulsion, into the first clinical studies. Their properties also make them attractive candidates for a variety of diagnostic and therapeutic applications including drug-delivery, diagnosis and treatment of cancerous and inflammatory diseases, as well as tumor-growth tracking. However, control over the thermal and acoustic stability of PCCAs both in vivo and in vitro has remained a challenge for expanding the potential utility of these agents in novel clinical applications. As such, our objective was to determine the stabilizing effects of layer-by-layer assemblies and its effect on both thermal and acoustic stability. METHODS We utilized layer-by-layer (LBL) assemblies to coat the outer PCCA membrane and characterized layering by measuring zeta potential and particle size. Stability studies were conducted by; 1) incubating the LBL-PCCAs at atmospheric pressure at 37∘C and 45∘C followed by; 2) ultrasound-mediated activation at 7.24 MHz and peak-negative pressures ranging from 0.71 - 5.48 MPa to ascertain nanodroplet activation and resultant microbubble persistence. The thermal and acoustic properties of decafluorobutane gas-condensed nanodroplets (DFB-NDs) layered with 6 and 10 layers of charge-alternating biopolymers, (LBL6NDs and LBL10NDs) respectively, were studied and compared to non-layered DFB-NDs. Half-life determinations were conducted at both 37∘C and 45∘C with acoustic droplet vaporization (ADV) measurements occurring at 23∘C. DISCUSSION Successful application of up to 10 layers of alternating positive and negatively charged biopolymers onto the surface membrane of DFB-NDs was demonstrated. Two major claims were substantiated in this study; namely, (1) biopolymeric layering of DFB-NDs imparts a thermal stability up to an extent; and, (2) both LBL6NDs and LBL10NDs did not appear to alter particle acoustic vaporization thresholds, suggesting that the thermal stability of the particle may not necessarily be coupled with particle acoustic vaporization thresholds. CONCLUSION Results demonstrate that the layered PCCAs had higher thermal stability, where the half-lifes of the LBLxNDs are significantly increased after incubation at 37∘C and 45∘C. Furthermore, the acoustic vaporization profiles the DFB-NDs, LBL6NDs, and LBL10NDs show that there is no statistically significant difference between the acoustic vaporization energy required to initiate acoustic droplet vaporization.
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Affiliation(s)
- Pedro Enrique Alcaraz
- College of Optical Sciences, University of Arizona, 1630 E University Blvd., Tucson, AZ 85721 United States; Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States; Department of Medical Imaging, University of Arizona, Tucson, AZ. 85719 United States
| | - Skylar J Davidson
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States
| | - Evan Shreeve
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States
| | - Rainee Meuschke
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States
| | - Marek Romanowski
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States; Department of Materials Science and Engineering, University of Arizona, Tucson, AZ 85719 United States
| | - Russell S Witte
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States; Department of Materials Science and Engineering, University of Arizona, Tucson, AZ 85719 United States; Department of Medical Imaging, University of Arizona, Tucson, AZ. 85719 United States
| | - Thomas R Porter
- Division of Cardiovascular Medicine, University of Nebraska Medical Center, Omaha, Nebraska
| | - Terry O Matsunaga
- Department of Biomedical Engineering, University of Arizona, Tucson, AZ 85719 United States; Department of Medical Imaging, University of Arizona, Tucson, AZ. 85719 United States.
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Loskutova K, Torras M, Zhao Y, Svagan AJ, Grishenkov D. Cellulose Nanofiber-Coated Perfluoropentane Droplets: Fabrication and Biocompatibility Study. Int J Nanomedicine 2023; 18:1835-1847. [PMID: 37051314 PMCID: PMC10085006 DOI: 10.2147/ijn.s397626] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 03/10/2023] [Indexed: 04/14/2023] Open
Abstract
Purpose To study the effect of cellulose nanofiber (CNF)-shelled perfluoropentane (PFP) droplets on the cell viability of 4T1 breast cancer cells with or without the addition of non-encapsulated paclitaxel. Methods The CNF-shelled PFP droplets were produced by mixing a CNF suspension and PFP using a homogenizer. The volume size distribution and concentration of CNF-shelled PFP droplets were estimated from images taken with an optical microscope and analyzed using Fiji software and an in-house Matlab script. The thermal stability was qualitatively assessed by comparing the size distribution and concentration of CNF-shelled PFP droplets at room temperature (~22°) and 37°C. The cell viability of 4T1 cells was measured using a 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Additionally, a hemolysis assay was performed to assess blood compatibility of CNF-shelled PFP droplets. Results The droplet diameter and concentration of CNF-shelled PFP droplets decreased after 48 hours at both room temperature and 37°C. In addition, the decrease in concentration was more significant at 37°C, from 3.50 ± 0.64×106 droplets/mL to 1.94 ± 0.10×106 droplets/mL, than at room temperature, from 3.65 ± 0.29×106 droplets/mL to 2.56 ± 0.22×106 droplets/mL. The 4T1 cell viability decreased with increased exposure time and concentration of paclitaxel, but it was not affected by the presence of CNF-shelled PFP droplets. No hemolysis was observed at any concentration of CNF-shelled PFP droplets. Conclusion CNF-shelled PFP droplets have the potential to be applied as drug carriers in ultrasound-mediated therapy.
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Affiliation(s)
- Ksenia Loskutova
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge, SE-141 57, Sweden
- Correspondence: Ksenia Loskutova, Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Hälsovägen 11C, Huddinge, SE-14157, Sweden, Tel +46 707 26 76 77, Email
| | - Mar Torras
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge, SE-141 57, Sweden
| | - Ying Zhao
- Department of Laboratory Medicine, Karolinska Institute, Huddinge, SE-141 57, Sweden
| | - Anna J Svagan
- Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Dmitry Grishenkov
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, Huddinge, SE-141 57, Sweden
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Xu M, Long W, Ling X, Hu X, Hong H, Peng Y, Cai T. Multifunctional theragnostic ultrasmall gold nanodot-encapsuled perfluorocarbon nanodroplets for laser-focused ultrasound sequence irradiation (LFSI)-based enhanced tumor ablation. J Mater Chem B 2022; 10:9816-9829. [PMID: 36426923 DOI: 10.1039/d2tb01775j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Despite the substantial potential of focused ultrasound therapy, its efficacy in cancer therapy has been limited due to the high cavitation threshold and safety concerns regarding the use of high-intensity energy pulses. Here, ultrasmall Au nanodot-loaded PEG-modified perfluorocarbon nanodroplets (Au-PFCnDs) were prepared and used as a therapeutic enhancer. A LFSI method was designed to achieve enhanced tumor ablation at a mild focused ultrasound (FUS) energy pulse with the assistance of the instinct photothermal effect of intratumor-permeable ultrasmall Au nanodots under 808 nm NIR laser irradiation. In addition to their therapeutic function, Au-PFCnDs can also generate multimodal images to provide information for tumor surveillance and treatment guidance. The experimental results also showed that the cRGD-targeted Au-PFCnDs could be more efficiently delivered into the tumor and selectively destroy tumors with no observable side effects on normal tissue under LFSI treatment.
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Affiliation(s)
- Menghan Xu
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
| | - Wei Long
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
| | - Xiang Ling
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
| | - Xiongwei Hu
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
| | - Hao Hong
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Medical School of Nanjing University, Nanjing 210093, China
| | - Yayun Peng
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
| | - Ting Cai
- State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing 210009, China.
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Chu J, Metcalfe P, Linford HV, Zhao S, Goycoolea FM, Chen S, Ye X, Holmes M, Orfila C. Short-time acoustic and hydrodynamic cavitation improves dispersibility and functionality of pectin-rich biopolymers from citrus waste. JOURNAL OF CLEANER PRODUCTION 2022; 330:129789. [PMID: 35095219 PMCID: PMC8783060 DOI: 10.1016/j.jclepro.2021.129789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 11/19/2021] [Accepted: 11/20/2021] [Indexed: 05/05/2023]
Abstract
Pectin is a valuable biopolymer used as a natural, clean label additive for thickening and gelling. However, industry faces issues with dispersibility and stability of pectin formulations. To address these issues, the effect of short processing time (30-180 s) with hydrodynamic (HC) and acoustic cavitation (AC) on the dispersibility and gelling functionality of mandarin pectin-rich polysaccharide (M-PRP) was investigated. Short-time processing with HC and AC did not affect polymer composition. HC, but not AC, decreased polydispersity index (PDI) from 0.78 to 0.68 compared to the control. Electron and atomic force microscopy showed that HC and AC decreased aggregation of fibrous and matrix polymers. Both treatments increased apparent viscosity significantly from 0.059 Pa s to 0.30 Pa s at 10 -s. The pectin dispersions showed good gelling capacity upon addition of calcium (final conc. 35 mM). HC and AC treatments for 150 s led to gels that were 7 and 4 times stronger (as measured by peak force) than the control with more homogeneous, less porous structures. In conclusion, short-time HC and AC can improve the dispersibility and functionality of citrus pectin without affecting composition, and are promising technologies to facilitate the use of pectin in industry applications.
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Affiliation(s)
- Jin Chu
- School of Food Science and Nutrition, University of Leeds, Leeds, UK
| | | | | | - Siying Zhao
- School of Food Science and Nutrition, University of Leeds, Leeds, UK
| | | | - Shiguo Chen
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, China
| | - Xingqian Ye
- College of Biosystems Engineering and Food Science, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, Zhejiang University, Hangzhou, China
| | - Melvin Holmes
- School of Food Science and Nutrition, University of Leeds, Leeds, UK
| | - Caroline Orfila
- School of Food Science and Nutrition, University of Leeds, Leeds, UK
- Corresponding author.
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Loskutova K, Olofsson K, Hammarström B, Wiklund M, Svagan AJ, Grishenkov D. Measuring the Compressibility of Cellulose Nanofiber-Stabilized Microdroplets Using Acoustophoresis. MICROMACHINES 2021; 12:mi12121465. [PMID: 34945315 PMCID: PMC8707857 DOI: 10.3390/mi12121465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 11/24/2021] [Accepted: 11/25/2021] [Indexed: 11/16/2022]
Abstract
Droplets with a liquid perfluoropentane core and a cellulose nanofiber shell have the potential to be used as drug carriers in ultrasound-mediated drug delivery. However, it is necessary to understand their mechanical properties to develop ultrasound imaging sequences that enable in vivo imaging of the vaporization process to ensure optimized drug delivery. In this work, the compressibility of droplets stabilized with cellulose nanofibers was estimated using acoustophoresis at three different acoustic pressures. Polyamide particles of known size and material properties were used for calibration. The droplet compressibility was then used to estimate the cellulose nanofiber bulk modulus and compare it to experimentally determined values. The results showed that the acoustic contrast factor for these droplets was negative, as the droplets relocated to pressure antinodes during ultrasonic actuation. The droplet compressibility was 6.6–6.8 ×10−10 Pa−1, which is higher than for water (4.4×10−10 Pa−1) but lower than for pure perfluoropentane (2.7×10−9 Pa−1). The compressibility was constant across different droplet diameters, which was consistent with the idea that the shell thickness depends on the droplet size, rather than being constant.
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Affiliation(s)
- Ksenia Loskutova
- Department of Biomedical Engineering and Health Systems, Royal Institute of Technology, KTH-Flemingsberg, SE-141 57 Huddinge, Sweden;
- Correspondence:
| | - Karl Olofsson
- Department of Applied Physics, Royal Institute of Technology, KTH-Albanova, SE-106 91 Stockholm, Sweden; (K.O.); (B.H.); (M.W.)
| | - Björn Hammarström
- Department of Applied Physics, Royal Institute of Technology, KTH-Albanova, SE-106 91 Stockholm, Sweden; (K.O.); (B.H.); (M.W.)
| | - Martin Wiklund
- Department of Applied Physics, Royal Institute of Technology, KTH-Albanova, SE-106 91 Stockholm, Sweden; (K.O.); (B.H.); (M.W.)
| | - Anna J. Svagan
- Department of Fibre and Polymer Technology, Royal Institute of Technology, KTH-Valhallavägen, SE-114 28 Stockholm, Sweden;
| | - Dmitry Grishenkov
- Department of Biomedical Engineering and Health Systems, Royal Institute of Technology, KTH-Flemingsberg, SE-141 57 Huddinge, Sweden;
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Song X, Loskutova K, Chen H, Shen G, Grishenkov D. Deriving acoustic properties for perfluoropentane droplets with viscoelastic cellulose nanofiber shell via numerical simulations. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:1750. [PMID: 34598597 DOI: 10.1121/10.0006046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
Perfluoropentane droplets with cellulose nanofibers (CNF) shells have demonstrated better stability and easier surface modification as ultrasound contrast agents and drug delivery vehicles. This paper presents a theoretical model assuming a four-phase state "inverse antibubble," with the core filled with gas perfluoropentane surrounded by liquid perfluoropentane. A continuous, incompressible, and viscoelastic stabilizing layer separates the core from the surrounding water. A parametric study is performed to predict the frequency-dependent attenuation coefficient, the speed of sound, and the resonance frequency of the droplets which have a mean diameter of 2.47 ± 0.95 μm. Results reveal that the CNF-stabilized perfluoropentane droplets can be modeled in a Rayleigh-Plesset like equation. We conclude that the shell strongly influences the acoustic behavior of the droplets and the resonance frequency largely depends on the initial gas cavity radius. More specifically, the peak attenuation coefficient and peak-to-peak speed of sound decrease with increasing shear modulus, shear viscosity, and shell thickness, while they increase with increasing gas cavity radius and concentration. The resonance frequency increases as shear modulus and shell thickness increase, while it decreases as shear viscosity and gas cavity radius increase. It is worth mentioning that droplet concentration has no effect on the resonance frequency.
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Affiliation(s)
- Xue Song
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Ksenia Loskutova
- Department of Biomedical Engineering and Health System, KTH Royal Institute of Technology, Stockholm, 10044, Sweden
| | - Hongjian Chen
- Department of Ultrasound in Medicine, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China
| | - Guofeng Shen
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Dmitry Grishenkov
- Department of Biomedical Engineering and Health System, KTH Royal Institute of Technology, Stockholm, 10044, Sweden
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9
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Vidallon MLP, Giles LW, Crawford S, Bishop AI, Tabor RF, de Campo L, Teo BM. Exploring the transition of polydopamine-shelled perfluorohexane emulsion droplets into microbubbles using small- and ultra-small-angle neutron scattering. Phys Chem Chem Phys 2021; 23:9843-9850. [PMID: 33908524 DOI: 10.1039/d1cp01146d] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Perfluorocarbon emulsion droplets are interesting colloidal systems with applications, ranging from diagnostics and theranostics to drug delivery, due to their controllable phase transition into microbubbles via heat application or acoustic droplet vapourisation. This work highlights the application of small- and ultra-small-angle neutron scattering (SANS and USANS, respectively), in combination with contrast variation techniques, in observing the in situ phase transition of polydopamine-stabilised perfluorohexane (PDA/PFH) emulsion droplets into microbubbles during heating. Results show peak USANS intensities at temperatures around 90 °C, which indicates that the phase transition of PDA/PFH emulsion droplets occurs at significantly higher temperatures than the bulk boiling point of pure liquid PFH (56 °C). Analysis and model fitting of the SANS and USANS data allowed us to estimate droplet sizes and interfacial properties at different temperatures (20 °C, 90 °C, and 20 °C after cooling), giving valuable insights about the transformation of these polydisperse emulsion droplet systems.
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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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