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Navarro-Becerra JA, Castillo JI, Borden MA. Effect of Poly(ethylene glycol) Configuration on Microbubble Pharmacokinetics. ACS Biomater Sci Eng 2024; 10:3331-3342. [PMID: 38600786 DOI: 10.1021/acsbiomaterials.3c01764] [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] [Indexed: 04/12/2024]
Abstract
Microbubbles (MBs) hold substantial promise for medical imaging and therapy; nonetheless, knowledge gaps persist between composition, structure, and in vivo performance, especially with respect to pharmacokinetics. Of particular interest is the role of the poly(ethylene glycol) (PEG) layer, which is thought to shield the MB against opsonization and rapid clearance but is also known to cause an antibody response upon multiple injections. The goal of this study was, therefore, to elucidate the role of the PEG layer in circulation persistence of MBs in the naïve animal (prior to an adaptive immune response). Here, we directly observe the number and size of individual MBs obtained from blood samples, unifying size and concentration into the microbubble volume dose (MVD) parameter. This approach enables direct evaluation of the pharmacokinetics of intact MBs, comprising both the lipid shell and gaseous core, rather than separately assessing the lipid or gas components. We examined the in vivo circulation persistence of 3 μm diameter phospholipid-coated MBs with three different mPEG2000 content: 2 mol % (mushroom), 5 mol % (intermediate), and 10 mol % (brush). MB size and concentration in the blood were evaluated by a hemocytometer analysis over 30 min following intravenous injections of 20 and 40 μL/kg MVD in Sprague-Dawley rats. Interestingly, pharmacokinetic analysis demonstrated that increasing PEG concentration on the MB surface resulted in faster clearance. This was evidenced by a 1.6-fold reduction in half-life and area under the curve (AUC) (p < 0.05) in the central compartment. Conversely, the AUC in the peripheral compartment increased with PEG density, suggesting enhanced MB trapping by the mononuclear phagocyte system. This was supported by an in vitro assay, which showed a significant rise in complement C3a activation with a higher PEG content. In conclusion, a minimal PEG concentration on the MB shell (mushroom configuration) was found to prolong circulation and mitigate immunogenicity.
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Affiliation(s)
- J Angel Navarro-Becerra
- Mechanical Engineering Department, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Jair I Castillo
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Mark A Borden
- Mechanical Engineering Department, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309, United States
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2
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Cattaneo M, Supponen O. Shell viscosity estimation of lipid-coated microbubbles. SOFT MATTER 2023; 19:5925-5941. [PMID: 37490014 DOI: 10.1039/d3sm00871a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
Understanding the shell rheology of ultrasound contrast agent microbubbles is vital for anticipating their bioeffects in clinical practice. Past studies using sophisticated acoustic and optical techniques have made enormous progress in this direction, enabling the development of shell models that adequately reproduce the nonlinear behaviour of the coated microbubble under acoustic excitation. However, there have also been puzzling discrepancies and missing physical explanations for the dependency of shell viscosity on the equilibrium bubble radius, which demands further experimental investigations. In this study, we aim to unravel the cause of such behaviour by performing a refined characterisation of the shell viscosity. We use ultra-high-speed microscopy imaging, optical trapping and wide-field fluorescence to accurately record the individual microbubble response upon ultrasound driving across a range of bubble sizes. An advanced model of bubble dynamics is validated and employed to infer the shell viscosity of single bubbles from their radial time evolution. The resulting values reveal a prominent variability of the shell viscosity of about an order of magnitude and no dependency on the bubble size, which is contrary to previous studies. We find that the method called bubble spectroscopy, which has been used extensively in the past to determine the shell viscosity, is highly sensitive to methodology inaccuracies, and we demonstrate through analytical arguments that the previously reported unphysical trends are an artifact of these biases. We also show the importance of correct bubble sizing, as errors in this aspect can also lead to unphysical trends in shell viscosity, when estimated through a nonlinear fitting from the time response of the bubble.
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Affiliation(s)
- Marco Cattaneo
- Institute of Fluid Dynamics, Department of Mechanical and Process Engineering, ETH Zürich, Sonneggstrasse 3, 8092 Zürich, Switzerland.
| | - Outi Supponen
- Institute of Fluid Dynamics, Department of Mechanical and Process Engineering, ETH Zürich, Sonneggstrasse 3, 8092 Zürich, Switzerland.
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Navarro-Becerra JA, Borden MA. Targeted Microbubbles for Drug, Gene, and Cell Delivery in Therapy and Immunotherapy. Pharmaceutics 2023; 15:1625. [PMID: 37376072 DOI: 10.3390/pharmaceutics15061625] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/18/2023] [Accepted: 05/26/2023] [Indexed: 06/29/2023] Open
Abstract
Microbubbles are 1-10 μm diameter gas-filled acoustically-active particles, typically stabilized by a phospholipid monolayer shell. Microbubbles can be engineered through bioconjugation of a ligand, drug and/or cell. Since their inception a few decades ago, several targeted microbubble (tMB) formulations have been developed as ultrasound imaging probes and ultrasound-responsive carriers to promote the local delivery and uptake of a wide variety of drugs, genes, and cells in different therapeutic applications. The aim of this review is to summarize the state-of-the-art of current tMB formulations and their ultrasound-targeted delivery applications. We provide an overview of different carriers used to increase drug loading capacity and different targeting strategies that can be used to enhance local delivery, potentiate therapeutic efficacy, and minimize side effects. Additionally, future directions are proposed to improve the tMB performance in diagnostic and therapeutic applications.
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Affiliation(s)
| | - Mark A Borden
- Mechanical Engineering Department, University of Colorado Boulder, Boulder, CO 80309, USA
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, CO 80309, USA
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Navarro-Becerra JA, Castillo JI, Di Ruzza F, Borden MA. Monodispersity Increases Adhesion Efficiency and Specificity for Ultrasound-Targeted Microbubbles. ACS Biomater Sci Eng 2023; 9:991-1001. [PMID: 36153974 DOI: 10.1021/acsbiomaterials.2c00528] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ultrasound molecular imaging with targeted microbubbles (MBs) can be used to noninvasively diagnose, monitor, and study the progression of different endothelial-associated diseases. Acoustic radiation force (Frad) can initiate and enhance MB adhesion at the target site. The goal of this study was to elucidate the effects of various MB parameters on Frad targeting. Monodisperse or polydisperse MBs with the immune-stealth cloaked (buried)-ligand architecture were conjugated with targeting RGD or nonspecific isotype control RAD peptides and then pumped through an αvβ3 integrin-coated microvessel phantom at a wall shear stress of 3.5 dyn/cm2. Targeting was assessed by measuring MB attachment for varying Frad time and frequency, as well as MB concentration and size distribution. We first confirmed that primary Frad is necessary to target the cloaked-ligand MBs. MB targeting increased monotonically with αvβ3 integrin density and Frad time. MB attachment and, to a lesser extent specificity, also increased when driven by Frad near resonance. MB targeting increased with MB concentration, although a shift in behavior was observed with increasing MB-MB interactions and aggregations forming from secondary Frad effects as MB concentration was increased. These secondary Frad effects reduced targeting specificity. Finally, after having validated our approach by testing different parameters with the appropriate controls, we then determined the effects of monodispersity on adhesion efficiency and specific targeting. We observed that both MB targeting efficiency and specificity were greatly enhanced for monodisperse vs polydisperse MBs. Analysis of videomicroscopy images indicated that secondary Frad effects may have disproportionally inhibited targeting of polydisperse MBs. In conclusion, our in vitro results indicate that monodisperse MBs driven near resonance and at a low concentration (∼106 MB/mL) can be used to maximize the adhesion efficiency (up to 88%) and specificity of RGD-MB targeting.
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Affiliation(s)
- J Angel Navarro-Becerra
- Mechanical Engineering Department, University of Colorado Boulder, Boulder, Colorado 80309-0427, United States
| | - Jair I Castillo
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309-0427, United States
| | - Federico Di Ruzza
- Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309-0427, United States.,Chemical Science and Technology Department, University of Rome Tor Vergata, Roma 00133, Italy
| | - Mark A Borden
- Mechanical Engineering Department, University of Colorado Boulder, Boulder, Colorado 80309-0427, United States.,Biomedical Engineering Program, University of Colorado Boulder, Boulder, Colorado 80309-0427, United States
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Counil C, Abenojar E, Perera R, Exner AA. Extrusion: A New Method for Rapid Formulation of High-Yield, Monodisperse Nanobubbles. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2200810. [PMID: 35587613 PMCID: PMC9233137 DOI: 10.1002/smll.202200810] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/24/2022] [Indexed: 06/03/2023]
Abstract
Shell-stabilized gas microbubbles (MB) and nanobubbles (NB) are frequently used for biomedical ultrasound imaging and therapeutic applications. While it is widely recognized that monodisperse bubbles can be more effective in these applications, the efficient formulation of uniform bubbles at high concentrations is difficult to achieve. Here, it is demonstrated that a standard mini-extruder setup, commonly used to make vesicles or liposomes, can be used to quickly and efficiently generate monodisperse NBs with high yield. In this highly reproducible technique, the NBs obtained have an average diameter of 0.16 ± 0.05 µm and concentration of 6.2 ± 1.8 × 1010 NBs mL-1 compared to 0.32 ± 0.1 µm and 3.2 ± 0.7 × 1011 mL-1 for NBs made using mechanical agitation. Parameters affecting the extrusion and NB generation process including the temperature, concentration of the lipid solution, and the number of passages through the extruder are also examined. Moreover, it is demonstrated that extruded NBs show a strong acoustic response in vitro and a strong and persistent US signal enhancement under nonlinear contrast enhanced ultrasound imaging in mice. The extrusion process is a new, efficient, and scalable technique that can be used to easily produce high yield smaller monodispersed nanobubbles.
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Affiliation(s)
- Claire Counil
- Department of Radiology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-7207, USA
| | - Eric Abenojar
- Department of Radiology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-7207, USA
| | - Reshani Perera
- Department of Radiology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-7207, USA
| | - Agata A Exner
- Department of Radiology, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-7207, USA
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Hafez AA, Salimi A, Jamali Z, Shabani M, Sheikhghaderi H. Overview of the application of inorganic nanomaterials in breast cancer diagnosis. INORG NANO-MET CHEM 2022. [DOI: 10.1080/24701556.2021.2025085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Asghar Ashrafi Hafez
- Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ahmad Salimi
- Department of Pharmacology and Toxicology, School of Pharmacy, Ardabil University of Medical Sciences, Ardabil, Iran
- Traditional Medicine and Hydrotherapy Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Zhaleh Jamali
- Student Research Committee, School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Mohammad Shabani
- Student Research Committee, School of Pharmacy, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Hiva Sheikhghaderi
- Student Research Committee, School of Paramedical, Kermanshah University of Medical Sciences, Kermanshah, Iran
- Bukan Shahid Gholipour Hospital, Urmia University of Medical Sciences, Bukan, Iran
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7
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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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Deprez J, Lajoinie G, Engelen Y, De Smedt SC, Lentacker I. Opening doors with ultrasound and microbubbles: Beating biological barriers to promote drug delivery. Adv Drug Deliv Rev 2021; 172:9-36. [PMID: 33705877 DOI: 10.1016/j.addr.2021.02.015] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/01/2021] [Accepted: 02/17/2021] [Indexed: 12/13/2022]
Abstract
Apart from its clinical use in imaging, ultrasound has been thoroughly investigated as a tool to enhance drug delivery in a wide variety of applications. Therapeutic ultrasound, as such or combined with cavitating nuclei or microbubbles, has been explored to cross or permeabilize different biological barriers. This ability to access otherwise impermeable tissues in the body makes the combination of ultrasound and therapeutics very appealing to enhance drug delivery in situ. This review gives an overview of the most important biological barriers that can be tackled using ultrasound and aims to provide insight on how ultrasound has shown to improve accessibility as well as the biggest hurdles. In addition, we discuss the clinical applicability of therapeutic ultrasound with respect to the main challenges that must be addressed to enable the further progression of therapeutic ultrasound towards an effective, safe and easy-to-use treatment tailored for drug delivery in patients.
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Affiliation(s)
- J Deprez
- Ghent Research Group on Nanomedicines, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - G Lajoinie
- Physics of Fluids Group, MESA+ Institute for Nanotechnology and Technical Medical (TechMed) Center, University of Twente, P.O. Box 217, 7500 AE Enschede, Netherlands
| | - Y Engelen
- Ghent Research Group on Nanomedicines, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - S C De Smedt
- Ghent Research Group on Nanomedicines, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
| | - I Lentacker
- Ghent Research Group on Nanomedicines, Department of Pharmaceutics, Ghent University, Ottergemsesteenweg 460, 9000 Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium
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9
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Air-Filled Bubbles Stabilized by Gold Nanoparticle/Photodynamic Dye Hybrid Structures for Theranostics. NANOMATERIALS 2021; 11:nano11020415. [PMID: 33562017 PMCID: PMC7915581 DOI: 10.3390/nano11020415] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/27/2021] [Accepted: 02/03/2021] [Indexed: 12/22/2022]
Abstract
Microbubbles have already reached clinical practice as ultrasound contrast agents for angiography. However, modification of the bubbles’ shell is needed to produce probes for ultrasound and multimodal (fluorescence/photoacoustic) imaging methods in combination with theranostics (diagnostics and therapeutics). In the present work, hybrid structures based on microbubbles with an air core and a shell composed of bovine serum albumin, albumin-coated gold nanoparticles, and clinically available photodynamic dyes (zinc phthalocyanine, indocyanine green) were shown to achieve multimodal imaging for potential applications in photodynamic therapy. Microbubbles with an average size of 1.5 ± 0.3 μm and concentration up to 1.2 × 109 microbubbles/mL were obtained and characterized. The introduction of the dye into the system reduced the solution’s surface tension, leading to an increase in the concentration and stability of bubbles. The combination of gold nanoparticles and photodynamic dyes’ influence on the fluorescent signal and probes’ stability is described. The potential use of the obtained probes in biomedical applications was evaluated using fluorescence tomography, raster-scanning optoacoustic microscopy and ultrasound response measurements using a medical ultrasound device at the frequency of 33 MHz. The results demonstrate the impact of microbubbles’ stabilization using gold nanoparticle/photodynamic dye hybrid structures to achieve probe applications in theranostics.
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10
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11
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Ultrasound. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00018-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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12
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Deep Tumor Penetration of Doxorubicin-Loaded Glycol Chitosan Nanoparticles Using High-Intensity Focused Ultrasound. Pharmaceutics 2020; 12:pharmaceutics12100974. [PMID: 33076520 PMCID: PMC7650702 DOI: 10.3390/pharmaceutics12100974] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/11/2020] [Accepted: 10/14/2020] [Indexed: 12/13/2022] Open
Abstract
The dense extracellular matrix (ECM) in heterogeneous tumor tissues can prevent the deep tumor penetration of drug-loaded nanoparticles, resulting in a limited therapeutic efficacy in cancer treatment. Herein, we suggest that the deep tumor penetration of doxorubicin (DOX)-loaded glycol chitosan nanoparticles (CNPs) can be improved using high-intensity focused ultrasound (HIFU) technology. Firstly, we prepared amphiphilic glycol chitosan-5β-cholanic acid conjugates that can self-assemble to form stable nanoparticles with an average of 283.7 ± 5.3 nm. Next, the anticancer drug DOX was simply loaded into the CNPs via a dialysis method. DOX-loaded CNPs (DOX-CNPs) had stable nanoparticle structures with an average size of 265.9 ± 35.5 nm in aqueous condition. In cultured cells, HIFU-treated DOX-CNPs showed rapid drug release and enhanced cellular uptake in A549 cells, resulting in increased cytotoxicity, compared to untreated DOX-CNPs. In ECM-rich A549 tumor-bearing mice, the tumor-targeting efficacy of intravenously injected DOX-CNPs with HIFU treatment was 1.84 times higher than that of untreated DOX-CNPs. Furthermore, the deep tumor penetration of HIFU-treated DOX-CNPs was clearly observed at targeted tumor tissues, due to the destruction of the ECM structure via HIFU treatment. Finally, HIFU-treated DOX-CNPs greatly increased the therapeutic efficacy at ECM-rich A549 tumor-bearing mice, compared to free DOX and untreated DOX-CNPs. This deep penetration of drug-loaded nanoparticles via HIFU treatment is a promising strategy to treat heterogeneous tumors with dense ECM structures.
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Prusty D, Nap RJ, Szleifer I, Olvera de la Cruz M. Charge regulation mechanism in end-tethered weak polyampholytes. SOFT MATTER 2020; 16:8832-8847. [PMID: 32901638 DOI: 10.1039/d0sm01323d] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Weak polyampholytes, containing oppositely charged dissociable groups, are expected to be responsive to changes in ionic conditions. Here, we determine structural and thermodynamic properties, including the charged groups' degrees of dissociation, of end-tethered weak polyampholyte layers as a function of salt concentration, pH, and the solvent quality. For diblock weak polyampholytes grafted by their acidic blocks, we find that the acidic monomers increase their charge while the basic monomers decrease their charge with decreasing salt concentration for pH values less than the pKa value of both monomers and vice versa when the pH > pKa. This complex charge regulation occurs because the electrostatic attraction between oppositely charged blocks is stronger than the repulsion between monomers with the same charge in both good and poor solvents when the screening by salt ions is weak. This is evidenced by the retraction of the top block into the bottom layer. In the case of poor solvent conditions to the basic block (the top block), we find lateral segregation of basic monomers into micelles, forming a two-dimensional hexagonal pattern on the surface at intermediate and high pH values for monovalent salt concentrations from 0.01 to 0.1 M. When the solvent is poor to both blocks, we find lateral segregation of the grafted acidic block into lamellae with longitudinal undulations of low and high acidic monomer density. By exploiting weak block polyampholytes, our work expands the parameter space for creating responsive surfaces stable over a wide range of pH and salt concentration.
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Affiliation(s)
- D Prusty
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA.
| | - R J Nap
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208, USA and Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, USA
| | - I Szleifer
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208, USA and Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, USA and Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - M Olvera de la Cruz
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA. and Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA and Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA
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15
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Molecular Ultrasound Imaging. NANOMATERIALS 2020; 10:nano10101935. [PMID: 32998422 PMCID: PMC7601169 DOI: 10.3390/nano10101935] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 02/07/2023]
Abstract
In the last decade, molecular ultrasound imaging has been rapidly progressing. It has proven promising to diagnose angiogenesis, inflammation, and thrombosis, and many intravascular targets, such as VEGFR2, integrins, and selectins, have been successfully visualized in vivo. Furthermore, pre-clinical studies demonstrated that molecular ultrasound increased sensitivity and specificity in disease detection, classification, and therapy response monitoring compared to current clinically applied ultrasound technologies. Several techniques were developed to detect target-bound microbubbles comprising sensitive particle acoustic quantification (SPAQ), destruction-replenishment analysis, and dwelling time assessment. Moreover, some groups tried to assess microbubble binding by a change in their echogenicity after target binding. These techniques can be complemented by radiation force ultrasound improving target binding by pushing microbubbles to vessel walls. Two targeted microbubble formulations are already in clinical trials for tumor detection and liver lesion characterization, and further clinical scale targeted microbubbles are prepared for clinical translation. The recent enormous progress in the field of molecular ultrasound imaging is summarized in this review article by introducing the most relevant detection technologies, concepts for targeted nano- and micro-bubbles, as well as their applications to characterize various diseases. Finally, progress in clinical translation is highlighted, and roadblocks are discussed that currently slow the clinical translation.
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Stride E, Segers T, Lajoinie G, Cherkaoui S, Bettinger T, Versluis M, Borden M. Microbubble Agents: New Directions. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:1326-1343. [PMID: 32169397 DOI: 10.1016/j.ultrasmedbio.2020.01.027] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/09/2020] [Accepted: 01/26/2020] [Indexed: 05/24/2023]
Abstract
Microbubble ultrasound contrast agents have now been in use for several decades and their safety and efficacy in a wide range of diagnostic applications have been well established. Recent progress in imaging technology is facilitating exciting developments in techniques such as molecular, 3-D and super resolution imaging and new agents are now being developed to meet their specific requirements. In parallel, there have been significant advances in the therapeutic applications of microbubbles, with recent clinical trials demonstrating drug delivery across the blood-brain barrier and into solid tumours. New agents are similarly being tailored toward these applications, including nanoscale microbubble precursors offering superior circulation times and tissue penetration. The development of novel agents does, however, present several challenges, particularly regarding the regulatory framework. This article reviews the developments in agents for diagnostic, therapeutic and "theranostic" applications; novel manufacturing techniques; and the opportunities and challenges for their commercial and clinical translation.
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Affiliation(s)
- Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK.
| | - Tim Segers
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Guillaume Lajoinie
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Samir Cherkaoui
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Thierry Bettinger
- Bracco Suisse SA - Business Unit Imaging, Global R&D, Plan-les-Ouates, Switzerland
| | - Michel Versluis
- Physics of Fluids Group, Technical Medical (TechMed) Centre, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
| | - Mark Borden
- Mechanical Engineering Department, University of Colorado, Boulder, CO, USA
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Pouliopoulos AN, Jimenez DA, Frank A, Robertson A, Zhang L, Kline-Schoder AR, Bhaskar V, Harpale M, Caso E, Papapanou N, Anderson R, Li R, Konofagou EE. Temporal stability of lipid-shelled microbubbles during acoustically-mediated blood-brain barrier opening. FRONTIERS IN PHYSICS 2020; 8:137. [PMID: 32457896 PMCID: PMC7250395 DOI: 10.3389/fphy.2020.00137] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Non-invasive blood-brain barrier (BBB) opening using focused ultrasound (FUS) is being tested as a means to locally deliver drugs into the brain. Such FUS therapies require injection of preformed microbubbles, currently used as contrast agents in ultrasound imaging. Although their behavior during exposure to imaging sequences has been well described, our understanding of microbubble stability within a therapeutic field is still not complete. Here, we study the temporal stability of lipid-shelled microbubbles during therapeutic FUS exposure in two timescales: the short time scale (i.e., μs of low-frequency ultrasound exposure) and the long time scale (i.e., days post-activation). We first simulated the microbubble response to low-frequency sonication, and found a strong correlation between viscosity and fragmentation pressure. Activated microbubbles had a concentration decay constant of 0.02 d-1 but maintained a quasi-stable size distribution for up to 3 weeks (< 10% variation). Microbubbles flowing through a 4-mm vessel within a tissue-mimicking phantom (5% gelatin) were exposed to therapeutic pulses (fc: 0.5 MHz, peak-negative pressure: 300 kPa, pulse length: 1 ms, pulse repetition frequency: 1 Hz, n=10). We recorded and analyzed their acoustic emissions, focusing on emitted energy and its temporal evolution, alongside the frequency content. Measurements were repeated with concentration-matched samples (107 microbubbles/ml) on day 0, 7, 14, and 21 after activation. Temporal stability decreased while inertial cavitation response increased with storage time both in vitro and in vivo, possibly due to changes in the shell lipid content. Using the same parameters and timepoints, we performed BBB opening in a mouse model (n=3). BBB opening volume measured through T1-weighted contrast-enhanced MRI was equal to 19.1 ± 7.1 mm3, 21.8 ± 14 mm3, 29.3 ± 2.5 mm3, and 38 ± 20.1 mm3 on day 0, 7, 14, and 21, respectively, showing no significant difference over time (p-value: 0.49). Contrast enhancement was 24.9 ± 1.7 %, 23.7 ± 11.7 %, 28.9 ± 5.3 %, and 35 ± 13.4 %, respectively (p-value: 0.63). In conclusion, the in-house made microbubbles studied here maintain their capacity to produce similar therapeutic effects over a period of 3 weeks after activation, as long as the natural concentration decay is accounted for. Future work should focus on stability of commercially available microbubbles and tailoring microbubble shell properties towards therapeutic applications.
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Affiliation(s)
| | - Daniella A. Jimenez
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Alexander Frank
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Alexander Robertson
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Lin Zhang
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Alina R. Kline-Schoder
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Vividha Bhaskar
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Mitra Harpale
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Elizabeth Caso
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Nicholas Papapanou
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Rachel Anderson
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Rachel Li
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
| | - Elisa E. Konofagou
- Department of Biomedical Engineering, Columbia University, New York City, New York 10032, USA
- Department of Radiology, Columbia University, New York City, New York 10032, USA
- Correspondence: Elisa E. Konofagou 351 Engineering Terrace, 1210 Amsterdam Avenue Mail Code: 8904, New York, NY, USA 10027 Phone: 212-342-0863, 212-854-9661
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Khatik R, Wang Z, Zhi D, Kiran S, Dwivedi P, Liang G, Qiu B, Yang Q. Integrin α vβ 3 Receptor Overexpressing on Tumor-Targeted Positive MRI-Guided Chemotherapy. ACS APPLIED MATERIALS & INTERFACES 2020; 12:163-176. [PMID: 31805767 DOI: 10.1021/acsami.9b16648] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Multifunctional nanomaterials with targeted imaging and chemotherapy have high demand with great challenge. Herein, we rationally aimed to design multifunctional drug delivery systems by RGD-modified chitosan (CH)-coated nanoneedles (NDs) of gadolinium arsenate (RGD-CH-Gd-AsNDs). These NDs have multifunctionality for imaging and targeted therapy. NDs on intravenous administration demonstrated significant accumulation of As ions/species in tumor tissues, which was monitored by the change in T1-weighted magnetic resonance (MR) imaging. Moreover, NDs were well opsonized in cells with high specificity, subsequently inducing apoptosis to the HepG2 cells. Consequent to this, the in vivo results demonstrated biosafety, enhanced tumor targeting, and tumor regression in a subcutaneously transplanted xenograft model in nude mice. These RGD-CH-Gd-AsNDs have great potential, and we anticipate that they could serve as a novel platform for real-time T1-weighted MR diagnosis and chemotherapy.
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19
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de Leon A, Perera R, Hernandez C, Cooley M, Jung O, Jeganathan S, Abenojar E, Fishbein G, Sojahrood AJ, Emerson CC, Stewart PL, Kolios MC, Exner AA. Contrast enhanced ultrasound imaging by nature-inspired ultrastable echogenic nanobubbles. NANOSCALE 2019; 11:15647-15658. [PMID: 31408083 PMCID: PMC6716144 DOI: 10.1039/c9nr04828f] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Advancement of ultrasound molecular imaging applications requires not only a reduction in size of the ultrasound contrast agents (UCAs) but also a significant improvement in the in vivo stability of the shell-stabilized gas bubble. The transition from first generation to second generation UCAs was marked by an advancement in stability as air was replaced by a hydrophobic gas, such as perfluoropropane and sulfur hexafluoride. Further improvement can be realized by focusing on how well the UCAs shell can retain the encapsulated gas under extreme mechanical deformations. Here we report the next generation of UCAs for which we engineered the shell structure to impart much better stability under repeated prolonged oscillation due to ultrasound, and large changes in shear and turbulence as it circulates within the body. By adapting an architecture with two layers of contrasting elastic properties similar to bacterial cell envelopes, our ultrastable nanobubbles (NBs) withstand continuous in vitro exposure to ultrasound with minimal signal decay and have a significant delay on the onset of in vivo signal decay in kidney, liver, and tumor. Development of ultrastable NBs can potentially expand the role of ultrasound in molecular imaging, theranostics, and drug delivery.
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Affiliation(s)
- Al de Leon
- Department of Radiology, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Reshani Perera
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Christopher Hernandez
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Michaela Cooley
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Olive Jung
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Selva Jeganathan
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Eric Abenojar
- Department of Radiology, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Grace Fishbein
- Department of Physics, Ryerson University, Toronto, ON, Canada
| | | | - Corey C Emerson
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - Phoebe L Stewart
- Department of Pharmacology and Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | | | - Agata A Exner
- Department of Radiology, Case Western Reserve University, Cleveland, OH 44106, USA. and Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
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20
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Choi Y, Lim S, Yoon HY, Kim BS, Kwon IC, Kim K. Tumor-targeting glycol chitosan nanocarriers: overcoming the challenges posed by chemotherapeutics. Expert Opin Drug Deliv 2019; 16:835-846. [DOI: 10.1080/17425247.2019.1648426] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yongwhan Choi
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seongbuk-gu, Seoul, Republic of Korea
| | - Seungho Lim
- Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seongbuk-gu, Seoul, Republic of Korea
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Hong Yeol Yoon
- Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seongbuk-gu, Seoul, Republic of Korea
| | - Byung-Soo Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Ick Chan Kwon
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seongbuk-gu, Seoul, Republic of Korea
| | - Kwangmeyung Kim
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seongbuk-gu, Seoul, Republic of Korea
- Center for Theragnosis, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seongbuk-gu, Seoul, Republic of Korea
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21
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Upadhyay A, Dalvi SV. Microbubble Formulations: Synthesis, Stability, Modeling and Biomedical Applications. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:301-343. [PMID: 30527395 DOI: 10.1016/j.ultrasmedbio.2018.09.022] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 05/12/2023]
Abstract
Microbubbles are increasingly being used in biomedical applications such as ultrasonic imaging and targeted drug delivery. Microbubbles typically range from 0.1 to 10 µm in size and consist of a protective shell made of lipids or proteins. The shell encapsulates a gaseous core containing gases such as oxygen, sulfur hexafluoride or perfluorocarbons. This review is a consolidated account of information available in the literature on research related to microbubbles. Efforts have been made to present an overview of microbubble synthesis techniques; microbubble stability; microbubbles as contrast agents in ultrasonic imaging and drug delivery vehicles; and side effects related to microbubble administration in humans. Developments related to the modeling of microbubble dissolution and stability are also discussed.
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Affiliation(s)
- Awaneesh Upadhyay
- Chemical Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, India
| | - Sameer V Dalvi
- Chemical Engineering, Indian Institute of Technology Gandhinagar, Gandhinagar, India.
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22
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Biological active matter aggregates: Inspiration for smart colloidal materials. Adv Colloid Interface Sci 2019; 263:38-51. [PMID: 30504078 DOI: 10.1016/j.cis.2018.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/02/2018] [Accepted: 11/20/2018] [Indexed: 12/16/2022]
Abstract
Aggregations of social organisms exhibit a remarkable range of properties and functionalities. Multiple examples, such as fire ants or slime mold, show how a population of individuals is able to overcome an existential threat by gathering into a solid-like aggregate with emergent functionality. Surprisingly, these aggregates are driven by simple rules, and their mechanisms show great parallelism among species. At the same time, great effort has been made by the scientific community to develop active colloidal materials, such as microbubbles or Janus particles, which exhibit similar behaviors. However, a direct connection between these two realms is still not evident, and it would greatly benefit future studies. In this review, we first discuss the current understanding of living aggregates, point out the mechanisms in their formation and explore the vast range of emergent properties. Second, we review the current knowledge in aggregated colloidal systems, the methods used to achieve the aggregations and their potential functionalities. Based on this knowledge, we finally identify a set of over-arching principles commonly found in biological aggregations, and further suggest potential future directions for the creation of bio-inspired colloid aggregations.
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23
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Slagle CJ, Thamm DH, Randall EK, Borden MA. Click Conjugation of Cloaked Peptide Ligands to Microbubbles. Bioconjug Chem 2018; 29:1534-1543. [DOI: 10.1021/acs.bioconjchem.8b00084] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Connor J. Slagle
- Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
| | | | | | - Mark A. Borden
- Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
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24
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Jablonowski LJ, Conover D, Teraphongphom NT, Wheatley MA. Manipulating multifaceted microbubble shell composition to target both TRAIL-sensitive and resistant cells. J Biomed Mater Res A 2018. [PMID: 29521001 DOI: 10.1002/jbm.a.36389] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This study represents the first attempt to combine surface TRAIL expression and doxorubicin co-encapsulation in a single drug delivery agent in the form of ultrasound-responsive microbubbles that shatter into fragments, or nanoshards, in an ultrasound beam. We compare customized microbubbles of different polymeric shell compositions, and investigate the effect of both shell composition and incorporation of doxorubicin on action against TRAIL-sensitive MDA-MB-231 and TRAIL-resistant MCF7 human breast adenocarcinoma cells. Ligation of TRAIL only significantly impacted MDA-MB-231 cells predominantly by apoptosis, and had minimal effect on MCF12A (normal control) cells. For all shell types, nanoshards had a greater effect (apoptotic death ranging from approximately 25% for 1 wt % LipidPEG to 50% for 100% PLA), reflecting the greater surface area and larger number of particles that ultrasound generates. Encapsulation of doxorubicin generated necrosis in all cell lines, but PEGylation produced less effective necrosis in all cell lines. Co-encapsulation of doxorubicin within the contrast agent shell increased MDA-MB-231 cell death to approximately 40-80%, representing a marked increase over TRAIL alone, reflecting the dramatic effect of shell composition. Additionally, shells that co-encapsulated TRAIL and doxorubicin resulted in approximately 30-60% death in TRAIL-resistant MCF7 human breast adenocarcinoma cells, compared with little apoptotic response in these cells from shells encapsulating TRAIL alone, demonstrating the sensitization effect of the drug. This work has resulted in production of a library of effective ultrasound-triggered, minimally immunogenic, targeted drug delivery agents for potential use in cancer therapy, and represents a promising multifaceted treatment to better serve the population with solid tumors. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1903-1915, 2018.
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Affiliation(s)
- Lauren J Jablonowski
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania, 19104
| | - Dolores Conover
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania, 19104
| | - Nutte T Teraphongphom
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania, 19104
| | - Margaret A Wheatley
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania, 19104
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25
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Jablonowski LJ, Teraphongphom NT, Wheatley MA. Drug Delivery from a Multi-faceted Ultrasound Contrast Agent: Influence of Shell Composition. Mol Pharm 2017; 14:3448-3456. [DOI: 10.1021/acs.molpharmaceut.7b00451] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Lauren J. Jablonowski
- School
of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
| | - Nutte T. Teraphongphom
- School
of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
| | - Margaret A. Wheatley
- School
of Biomedical Engineering, Science, and Health Systems, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, United States
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26
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Jin Q, Lin CY, Kang ST, Chang YC, Zheng H, Yang CM, Yeh CK. Superhydrophobic silica nanoparticles as ultrasound contrast agents. ULTRASONICS SONOCHEMISTRY 2017; 36:262-269. [PMID: 28069209 DOI: 10.1016/j.ultsonch.2016.12.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/30/2016] [Accepted: 12/01/2016] [Indexed: 06/06/2023]
Abstract
Microbubbles have been widely studied as ultrasound contrast agents for diagnosis and as drug/gene carriers for therapy. However, their size and stability (lifetime of 5-12min) limited their applications. The development of stable nanoscale ultrasound contrast agents would therefore benefit both. Generating bubbles persistently in situ would be one of the promising solutions to the problem of short lifetime. We hypothesized that bubbles could be generated in situ by providing stable air nuclei since it has been found that the interfacial nanobubbles on a hydrophobic surface have a much longer lifetime (orders of days). Mesoporous silica nanoparticles (MSNs) with large surface areas and different levels of hydrophobicity were prepared to test our hypothesis. It is clear that the superhydrophobic and porous nanoparticles exhibited a significant and strong contrast intensity compared with other nanoparticles. The bubbles generated from superhydrophobic nanoparticles sustained for at least 30min at a MI of 1.0, while lipid microbubble lasted for about 5min at the same settings. In summary MSNs have been transformed into reliable bubble precursors by making simple superhydrophobic modification, and made into a promising contrast agent with the potentials to serve as theranostic agents that are sensitive to ultrasound stimulation.
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Affiliation(s)
- Qiaofeng Jin
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Yu Lin
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Shih-Tsung Kang
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Yuan-Chih Chang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Hairong Zheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen China
| | - Chia-Min Yang
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan.
| | - Chih-Kuang Yeh
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.
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27
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Lin WW, Hsieh YC, Cheng YA, Chuang KH, Huang CC, Chuang CH, Chen IJ, Cheng KW, Lu YC, Cheng TC, Wang YT, Roffler SR, Cheng TL. Optimization of an Anti-poly(ethylene glycol) (anti-PEG) Cell-Based Capture System To Quantify PEG and PEGylated Molecules. Anal Chem 2016; 88:12371-12379. [DOI: 10.1021/acs.analchem.6b03614] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Wen-Wei Lin
- Institute
of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | | | | | - Kuo-Hsiang Chuang
- Graduate
Institute of Pharmacognosy, Taipei Medical University, Taipei, Taiwan
| | | | | | | | - Kai-Wen Cheng
- Institute
of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
| | | | | | | | - Steve R. Roffler
- Institute
of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Tian-Lu Cheng
- Institute
of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
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28
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Jablonowski LJ, Alfego D, Andorko JI, Eisenbrey JR, Teraphongphom N, Wheatley MA. Balancing stealth and echogenic properties in an ultrasound contrast agent with drug delivery potential. Biomaterials 2016; 103:197-206. [DOI: 10.1016/j.biomaterials.2016.06.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 06/09/2016] [Accepted: 06/17/2016] [Indexed: 12/16/2022]
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29
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Upadhyay A, Dalvi SV. Synthesis, characterization and stability of BSA-encapsulated microbubbles. RSC Adv 2016. [DOI: 10.1039/c5ra24304a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this work, we present an account of experimental studies performed for the synthesis, shelf stability andin vitrostability of microbubbles made from perfluorobutane (PFB) gas and coated in a shell of Bovine Serum Albumin (BSA).
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Affiliation(s)
- Awaneesh Upadhyay
- Chemical Engineering
- Indian Institute of Technology Gandhinagar
- Chandkheda 382424
- India
| | - Sameer V. Dalvi
- Chemical Engineering
- Indian Institute of Technology Gandhinagar
- Chandkheda 382424
- India
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30
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Design of Microbubbles for Gene/Drug Delivery. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:191-204. [PMID: 26486339 DOI: 10.1007/978-3-319-22536-4_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The role of ultrasound contrast agents (UCA) initially designed for diagnosis has evolved towards a therapeutic use. Ultrasound (US) for triggered drug delivery has many advantages. In particular, it enables a high spatial control of drug release, thus potentially allowing activation of drug delivery only in the targeted region, and not in surrounding healthy tissue. Moreover, UCA imaging can also be used firstly to precisely locate the target region to, and then used to monitor the drug delivery process by tracking the location of release occurrence. All these features make UCA and ultrasound attractive means to mediate drug delivery. The three main potential clinical indications for drug/gene US delivery are (i) the cardiovascular system, (ii) the central nervous system for small molecule delivery, and (iii) tumor therapy using cytotoxic drugs. Although promising results have been achieved in preclinical studies in various animal models, still very few examples of clinical use have been reported. In this chapter will be addressed the aspects pertaining to UCA formulation (chemical composition, mode of preparation, analytical methods…) and the requirement for a potential translation into the clinic following approval by regulatory authorities.
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31
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Drug-Loaded Perfluorocarbon Nanodroplets for Ultrasound-Mediated Drug Delivery. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:221-41. [DOI: 10.1007/978-3-319-22536-4_13] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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32
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Wu Y, Yang C, Lai Q, Zhang Q, Wang W, Yuan Z. Fabrication of thermo-sensitive complex micelles for reversible cell targeting. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2015; 26:255. [PMID: 26449445 DOI: 10.1007/s10856-015-5584-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Accepted: 09/25/2015] [Indexed: 06/05/2023]
Abstract
To ideally solve the contradiction between enhanced cellular uptake and prolonged blood circulation, reversible targeting polymeric micelles based on the expanding and shrinking behavior of a temperature-responsive polymer were developed. The micelle contained a hydrophobic PCL core and a mixed shell consisting of poly(N-isopropylacrylamide) (PNIPAAm) and biotin-terminated poly(ethylene glycol) (Biotin-PEG), and its targeting ability could be switched on/off by temperature. The cellular uptake of the complex polymeric micelles was studied. The results from a quantitative enzyme-linked immunosorbent assay (ELISA) indicated that the surface biotin content increased by as much as 11.6-fold when the temperature increased above the lower critical solution temperature (LCST). More importantly, the ELISA confirmed that biotin-mediated targeting on the surface was reversibly switched on and off for at least five cycles. In addition, the results from quantitative flow cytometry and confocal spectroscopy indicated that the cellular uptake of the targeted micelles at temperatures above the LCST was much higher than that at temperatures below the LCST. This complex polymeric micelle with reversible targeting property could be a promising alternative for drug delivery.
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Affiliation(s)
- Yukun Wu
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China
| | - Chengling Yang
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China
| | - Quanyong Lai
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China
| | - Qian Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China
| | - Wei Wang
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China
| | - Zhi Yuan
- Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry, Nankai University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300071, China.
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33
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Kheirolomoom A, Kim CW, Seo JW, Kumar S, Son DJ, Gagnon MKJ, Ingham ES, Ferrara KW, Jo H. Multifunctional Nanoparticles Facilitate Molecular Targeting and miRNA Delivery to Inhibit Atherosclerosis in ApoE(-/-) Mice. ACS NANO 2015; 9:8885-97. [PMID: 26308181 PMCID: PMC4581466 DOI: 10.1021/acsnano.5b02611] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/26/2015] [Indexed: 05/18/2023]
Abstract
The current study presents an effective and selective multifunctional nanoparticle used to deliver antiatherogenic therapeutics to inflamed pro-atherogenic regions without off-target changes in gene expression or particle-induced toxicities. MicroRNAs (miRNAs) regulate gene expression, playing a critical role in biology and disease including atherosclerosis. While anti-miRNA are emerging as therapeutics, numerous challenges remain due to their potential off-target effects, and therefore the development of carriers for selective delivery to diseased sites is important. Yet, co-optimization of multifunctional nanoparticles with high loading efficiency, a hidden cationic domain to facilitate lysosomal escape and a dense, stable incorporation of targeting moieties is challenging. Here, we create coated, cationic lipoparticles (CCLs), containing anti-miR-712 (∼1400 molecules, >95% loading efficiency) within the core and with a neutral coating, decorated with 5 mol % of peptide (VHPK) to target vascular cell adhesion molecule 1 (VCAM1). Optical imaging validated disease-specific accumulation as anti-miR-712 was efficiently delivered to inflamed mouse aortic endothelial cells in vitro and in vivo. As with the naked anti-miR-712, the delivery of VHPK-CCL-anti-miR-712 effectively downregulated the d-flow induced expression of miR-712 and also rescued the expression of its target genes tissue inhibitor of metalloproteinase 3 (TIMP3) and reversion-inducing-cysteine-rich protein with kazal motifs (RECK) in the endothelium, resulting in inhibition of metalloproteinase activity. Moreover, an 80% lower dose of VHPK-CCL-anti-miR-712 (1 mg/kg dose given twice a week), as compared with naked anti-miR-712, prevented atheroma formation in a mouse model of atherosclerosis. While delivery of naked anti-miR-712 alters expression in multiple organs, miR-712 expression in nontargeted organs was unchanged following VHPK-CCL-anti-miR-712 delivery.
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Affiliation(s)
- Azadeh Kheirolomoom
- Department of Biomedical Engineering, University of California, Davis, California 95616, United States
| | - Chan Woo Kim
- Wallace H. Coulter Department of Biomedical Engineering and Division of Cardiology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
| | - Jai Woong Seo
- Department of Biomedical Engineering, University of California, Davis, California 95616, United States
| | - Sandeep Kumar
- Wallace H. Coulter Department of Biomedical Engineering and Division of Cardiology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
| | - Dong Ju Son
- Wallace H. Coulter Department of Biomedical Engineering and Division of Cardiology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
| | - M. Karen J. Gagnon
- Department of Biomedical Engineering, University of California, Davis, California 95616, United States
| | - Elizabeth S. Ingham
- Department of Biomedical Engineering, University of California, Davis, California 95616, United States
| | - Katherine W. Ferrara
- Department of Biomedical Engineering, University of California, Davis, California 95616, United States
- Address correspondence to ,
| | - Hanjoong Jo
- Wallace H. Coulter Department of Biomedical Engineering and Division of Cardiology, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, United States
- Address correspondence to ,
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Ultrasound molecular imaging of tumor angiogenesis with a neuropilin-1-targeted microbubble. Biomaterials 2015; 56:104-13. [PMID: 25934284 DOI: 10.1016/j.biomaterials.2015.03.043] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/15/2015] [Accepted: 03/20/2015] [Indexed: 02/06/2023]
Abstract
Ultrasound molecular imaging has great potential to impact early disease diagnosis, evaluation of disease progression and the development of target-specific therapy. In this paper, two neuropilin-1 (NRP) targeted peptides, CRPPR and ATWLPPR, were conjugated onto the surface of lipid microbubbles (MBs) to evaluate molecular imaging of tumor angiogenesis in a breast cancer model. Development of a molecular imaging agent using CRPPR has particular importance due to the previously demonstrated internalizing capability of this and similar ligands. In vitro, CRPPR MBs bound to an NRP-expressing cell line 2.6 and 15.6 times more than ATWLPPR MBs and non-targeted (NT) MBs, respectively, and the binding was inhibited by pretreating the cells with an NRP antibody. In vivo, the backscattered intensity within the tumor, relative to nearby vasculature, increased over time during the ∼6 min circulation of the CRPPR-targeted contrast agents providing high contrast images of angiogenic tumors. Approximately 67% of the initial signal from CRPPR MBs remained bound after the majority of circulating MBs had cleared (8 min), 8 and 4.5 times greater than ATWLPPR and NT MBs, respectively. Finally, at 7-21 days after the first injection, we found that CRPPR MBs cleared faster from circulation and tumor accumulation was reduced likely due to a complement-mediated recognition of the targeted microbubble and a decrease in angiogenic vasculature, respectively. In summary, we find that CRPPR MBs specifically bind to NRP-expressing cells and provide an effective new agent for molecular imaging of angiogenesis.
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Dove JD, Mountford PA, Murray TW, Borden MA. Engineering optically triggered droplets for photoacoustic imaging and therapy. BIOMEDICAL OPTICS EXPRESS 2014; 5:4417-27. [PMID: 25574448 PMCID: PMC4285615 DOI: 10.1364/boe.5.004417] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 11/20/2014] [Accepted: 11/21/2014] [Indexed: 05/20/2023]
Abstract
Liquid perfluorocarbon (PFC) droplets incorporating optical absorbers can be vaporized through photothermal heating using a pulsed laser source. Here, we report on the effect of droplet core material on the optical fluence required to produce droplet vaporization. We fabricate gold nanoparticle templated microbubbles filled with various PFC gases (C3F8, C4F10, and C5F12) and apply pressure to condense them into droplets. The core material is found to have a strong effect on the threshold optical fluence, with lower boiling point droplets allowing for vaporization at lower laser fluence. The impact of droplet size on vaporization threshold is discussed, as well as a proposed mechanism for the relatively broad distribution of vaporization thresholds observed within a droplet population with the same core material. We propose that the control of optical vaporization threshold enabled by engineering the droplet core may find application in contrast enhanced photoacoustic imaging and therapy.
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Affiliation(s)
- Jacob D. Dove
- Department of Mechanical Engineering, University of Colorado Boulder, 427 UCB, Boulder, Colorado 80309,
USA
| | - Paul A. Mountford
- Department of Mechanical Engineering, University of Colorado Boulder, 427 UCB, Boulder, Colorado 80309,
USA
| | - Todd W. Murray
- Department of Mechanical Engineering, University of Colorado Boulder, 427 UCB, Boulder, Colorado 80309,
USA
| | - Mark A. Borden
- Department of Mechanical Engineering, University of Colorado Boulder, 427 UCB, Boulder, Colorado 80309,
USA
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36
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Multi-modal detection of colon malignancy by NIR-tagged recognition polymers and ultrasound contrast agents. Int J Pharm 2014; 478:504-16. [PMID: 25437110 DOI: 10.1016/j.ijpharm.2014.11.066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/27/2014] [Indexed: 12/14/2022]
Abstract
To increase colonoscopy capability to discriminate benign from malignant polyps, we suggest combining two imaging approaches based on targeted polymeric platforms. Water-soluble cationized polyacrylamide (CPAA) was tagged with the near infrared (NIR) dye IR-783-S-Ph-COOH to form Flu-CPAA. The recognition peptide VRPMPLQ (reported to bind specifically to CRC tissues) was then conjugated with the Flu-CPAA to form Flu-CPAA-Pep which was then incorporated into echogenic microbubbles (MBs) made of polylactic acid (PLA) that are highly responsive to ultrasound. The ultimate design includes intravenous administration combined with local ultrasound and intra-colon inspection at the NIR range. In this proof of principle study PLA MBs were prepared by the double emulsion technique and loaded with several types of Flu-CPAA-Pep polymers. After insonation the submicron PLA fragments (SPF)-containing Flu-CPAA-Pep were examined in vitro for their ability to attach to colon cancer cells and in vivo (DMH induced rat model) for their ability to attach to colon malignant tissues and compared to the specific attachment of the free Flu-CPAA-Pep. The generation of SPF-containing Flu-CPAA-Pep resulted in a tissue attachment similar to that of the free, unloaded Flu-CPAA-Pep. The addition of VRPMPLQ to the polymeric backbone of the Flu-CPAA reduced cytotoxicity and improved the specific binding.
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Chuang KH, Kao CH, Roffler SR, Lu SJ, Cheng TC, Wang YM, Chuang CH, Hsieh YC, Wang YT, Wang JY, Weng KY, Cheng TL. Development of an Anti-Methoxy Poly(ethylene glycol) (α-mPEG) Cell-Based Capture System to Measure mPEG and mPEGylated Molecules. Macromolecules 2014. [DOI: 10.1021/ma501156r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kuo-Hsiang Chuang
- Graduate
Institute of Pharmacognosy, Taipei Medical University, 250 Wuxing
Street, Taipei 11031, Taiwan
- Ph.D. Program
for Clinical Drug Discovery from Botanical Herbs, Taipei Medical University, 250 Wuxing Street, Taipei 11031, Taiwan
| | - Chien-Han Kao
- Graduate
Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Steve R. Roffler
- Institute
of Biomedical Sciences, Academia Sinica, 128 Academia Road, Section 2, Taipei 11529, Taiwan
| | - Ssu-Jung Lu
- Department
of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Ta-Chun Cheng
- Graduate
Institute of Pharmacognosy, Taipei Medical University, 250 Wuxing
Street, Taipei 11031, Taiwan
| | - Yun-Ming Wang
- Department
of Biological Science and Technology, National Chiao Tung University, 1001
University Road, Hsinchu 30010, Taiwan
| | - Chih-Hung Chuang
- Department
of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Yuan-Chin Hsieh
- Graduate
Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Yeng-Tseng Wang
- Department
of Biochemistry, College of Medicine, Kaohsiung Medical University, 100
Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Jaw-Yuan Wang
- Graduate
Institute of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
- Department
of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
| | - Kuo-Yi Weng
- Division
of Rheumatology, Ten Chan General Hospital, 155 Yanping Road, Chung-Li, Taoyuan 32043, Taiwan
| | - Tian-Lu Cheng
- Department
of Biomedical Science and Environmental Biology, Kaohsiung Medical University, 100 Shih-Chuan first Road, Kaohsiung 80708, Taiwan
- Institute
of Biomedical Sciences, National Sun Yat-Sen University, 70 Lienhai
Road, Kaohsiung 80424, Taiwan
- Center
for Biomarkers and Biotech Drugs, Kaohsiung Medical University, 100
Shih-Chuan first Road, Kaohsiung 80708, Taiwan
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Izamis ML, Efstathiades A, Keravnou C, Georgiadou S, Martins PN, Averkiou MA. Effects of air embolism size and location on porcine hepatic microcirculation in machine perfusion. Liver Transpl 2014; 20:601-11. [PMID: 24478135 DOI: 10.1002/lt.23838] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Accepted: 01/05/2014] [Indexed: 02/07/2023]
Abstract
The handling of donor organs frequently introduces air into the microvasculature, but little is known about the extent of the damage caused as a function of the embolism size and distribution. Here we introduced embolisms of different sizes into the portal vein, the hepatic artery, or both during the flushing stage of porcine liver procurement. The outcomes were evaluated during 3 hours of machine perfusion and were compared to the outcomes of livers with no embolisms. Dynamic contrast-enhanced ultrasound (DCEUS) was used to assess the perfusion quality, and it demonstrated that embolisms tended to flow mostly into the left lobe, occasionally into the right lobe, and rarely into the caudate lobe. Major embolisms could disrupt the flow entirely, whereas minor embolisms resulted in reduced or heterogeneous flow. Embolisms occasionally migrated to different regions of the same lobe and, regardless of their size, caused a general deterioration in the flow over time. Histological damage resulted primarily when both vessels of the liver were compromised, whereas bile production was diminished in livers that had arterial embolisms. Air embolisms produced a dose-dependent increase in vascular resistance and a decline in oxygen consumption. This is the first article to quantify the impact of air embolisms on microcirculation in an experimental model, and it demonstrates that air embolisms have the capacity to degrade the integrity of donor organs. The extent of organ damage is strongly dependent on the size and distribution of air embolisms. The diagnosis of embolism severity can be safely and easily made with DCEUS.
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Affiliation(s)
- Maria-Louisa Izamis
- Department of Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus
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Paoli EE, Ingham ES, Zhang H, Mahakian LM, Fite BZ, Gagnon MK, Tam S, Kheirolomoom A, Cardiff RD, Ferrara KW. Accumulation, internalization and therapeutic efficacy of neuropilin-1-targeted liposomes. J Control Release 2014; 178:108-17. [PMID: 24434424 DOI: 10.1016/j.jconrel.2014.01.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 01/04/2014] [Accepted: 01/06/2014] [Indexed: 12/31/2022]
Abstract
Advancements in liposomal drug delivery have produced long circulating and very stable drug formulations. These formulations minimize systemic exposure; however, unfortunately, therapeutic efficacy has remained limited due to the slow diffusion of liposomal particles within the tumor and limited release or uptake of the encapsulated drug. Here, the carboxyl-terminated CRPPR peptide, with affinity for the receptor neuropilin-1 (NRP), which is expressed on both endothelial and cancer cells, was conjugated to liposomes to enhance the tumor accumulation. Using a pH sensitive probe, liposomes were optimized for specific NRP binding and subsequent cellular internalization using in vitro cellular assays. Liposomes conjugated with the carboxyl-terminated CRPPR peptide (termed C-LPP liposomes) bound to the NRP-positive primary prostatic carcinoma cell line (PPC-1) but did not bind to the NRP-negative PC-3 cell line, and binding was observed with liposomal peptide concentrations as low as 0.16mol%. Binding of the C-LPP liposomes was receptor-limited, with saturation observed at high liposome concentrations. The identical peptide sequence bearing an amide terminus did not bind specifically, accumulating only with a high (2.5mol%) peptide concentration and adhering equally to NRP positive and negative cell lines. The binding of C-LPP liposomes conjugated with 0.63mol% of the peptide was 83-fold greater than liposomes conjugated with the amide version of the peptide. Cellular internalization was also enhanced with C-LPP liposomes, with 80% internalized following 3h incubation. Additionally, fluorescence in the blood pool (~40% of the injected dose) was similar for liposomes conjugated with 0.63mol% of carboxyl-terminated peptide and non-targeted liposomes at 24h after injection, indicating stable circulation. Prior to doxorubicin treatment, in vivo tumor accumulation and vascular targeting were increased for peptide-conjugated liposomes compared to non-targeted liposomes based on confocal imaging of a fluorescent cargo, and the availability of the vascular receptor was confirmed with ultrasound molecular imaging. Finally, over a 4-week course of therapy, tumor knockdown resulting from doxorubicin-loaded, C-LPP liposomes was similar to non-targeted liposomes in syngeneic tumor-bearing FVB mice and C-LPP liposomes reduced doxorubicin accumulation in the skin and heart and eliminated skin toxicity. Taken together, our results demonstrate that a carboxyl-terminated RXXR peptide sequence, conjugated to liposomes at a concentration of 0.63mol%, retains long circulation but enhances binding and internalization, and reduces toxicity.
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Affiliation(s)
- Eric E Paoli
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Elizabeth S Ingham
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Hua Zhang
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Lisa M Mahakian
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Brett Z Fite
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - M Karen Gagnon
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Sarah Tam
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Azadeh Kheirolomoom
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Robert D Cardiff
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
| | - Katherine W Ferrara
- University of California, Davis, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, CA 95616, USA.
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40
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Nakatsuka MA, Barback CV, Fitch KR, Farwell AR, Esener SC, Mattrey RF, Cha JN, Goodwin AP. In vivo ultrasound visualization of non-occlusive blood clots with thrombin-sensitive contrast agents. Biomaterials 2013; 34:9559-65. [PMID: 24034499 DOI: 10.1016/j.biomaterials.2013.08.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Accepted: 08/14/2013] [Indexed: 10/26/2022]
Abstract
The use of microbubbles as ultrasound contrast agents is one of the primary methods to diagnose deep venous thrombosis. However, current microbubble imaging strategies require either a clot sufficiently large to produce a circulation filling defect or a clot with sufficient vascularization to allow for targeted accumulation of contrast agents. Previously, we reported the design of a microbubble formulation that modulated its ability to generate ultrasound contrast from interaction with thrombin through incorporation of aptamer-containing DNA crosslinks in the encapsulating shell, enabling the measurement of a local chemical environment by changes in acoustic activity. However, this contrast agent lacked sufficient stability and lifetime in blood to be used as a diagnostic tool. Here we describe a PEG-stabilized, thrombin-activated microbubble (PSTA-MB) with sufficient stability to be used in vivo in circulation with no change in biomarker sensitivity. In the presence of actively clotting blood, PSTA-MBs showed a 5-fold increase in acoustic activity. Specificity for the presence of thrombin and stability under constant shear flow were demonstrated in a home-built in vitro model. Finally, PSTA-MBs were able to detect the presence of an active clot within the vena cava of a rabbit sufficiently small as to not be visible by current non-specific contrast agents. By activating in non-occlusive environments, these contrast agents will be able to detect clots not diagnosable by current contrast agents.
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Affiliation(s)
- Matthew A Nakatsuka
- Department of Nanoengineering, University of California, San Diego, 9500 Gilman Dr. #0448, La Jolla, CA 92093-0448, USA
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41
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Morlieras J, Dufort S, Sancey L, Truillet C, Mignot A, Rossetti F, Dentamaro M, Laurent S, Vander Elst L, Muller RN, Antoine R, Dugourd P, Roux S, Perriat P, Lux F, Coll JL, Tillement O. Functionalization of small rigid platforms with cyclic RGD peptides for targeting tumors overexpressing αvβ3-integrins. Bioconjug Chem 2013; 24:1584-97. [PMID: 23978076 DOI: 10.1021/bc4002097] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Gadolinium based Small Rigid Plaforms (SRPs) have previously demonstrated their efficiency for multimodal imaging and radiosensitization. Since the RGD sequence is well-known to be highly selective for αvβ3 integrins, a cyclic pentapeptide containing the RGD motif (cRGDfK) has been grafted onto the SRP surface. An appropriate protocol led to the grafting of two targeting ligands per nano-object. The resulting nanoparticles have demonstrated a strong association with αvβ3 integrins in comparison with cRADfK grafted SRPs as negative control. Flow cytometry and fluorescence microscopy have also been used to highlight the ability of the nanoparticles to target efficiently HEK293(β3) and U87MG cells. Finally the grafted radiosensitizing nanoparticles were intravenously injected into Nude mice bearing subcutaneous U87MG tumors and the signal observed by optical imaging was twice as high for SRP-cRGDfK compared to their negative analogue.
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Affiliation(s)
- Jessica Morlieras
- Laboratoire de Physico-Chimie des Matériaux Luminescents, UMR 5620 CNRS - Université Claude Bernard Lyon 1, 69622 Villeurbanne Cedex, France
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42
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Borden MA, Streeter JE, Sirsi SR, Dayton PA. In vivo demonstration of cancer molecular imaging with ultrasound radiation force and buried-ligand microbubbles. Mol Imaging 2013; 12:357-363. [PMID: 23981781 PMCID: PMC4494687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023] Open
Abstract
In designing targeted contrast agent materials for imaging, the need to present a targeting ligand for recognition and binding by the target is counterbalanced by the need to minimize interactions with plasma components and to avoid recognition by the immune system. We have previously reported on a microbubble imaging probe for ultrasound molecular imaging that uses a buried-ligand surface architecture to minimize unwanted interactions and immunogenicity. Here we examine for the first time the utility of this approach for in vivo molecular imaging. In accordance with previous results, we showed a threefold increase in circulation persistence through the tumor of a fibrosarcoma model in comparison with controls. The buried-ligand microbubbles were then activated for targeted adhesion through the application of noninvasive ultrasound radiation forces applied specifically to the tumor region. Using a clinical ultrasound scanner, microbubbles were activated, imaged, and silenced. The results showed visually conspicuous images of tumor neovasculature and a twofold increase in ultrasound radiation force enhancement of acoustic contrast intensity for buried-ligand microbubbles, whereas no such increase was found for exposed-ligand microbubbles. We therefore conclude that the use of acoustically active buried-ligand microbubbles for ultrasound molecular imaging bridges the demand for low immunogenicity with the necessity of maintaining targeting efficacy and imaging conspicuity in vivo.
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Affiliation(s)
- Mark A Borden
- Department of Mechanical Engineering, University of Colorado, CO 8030, USA.
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Borden MA, Streeter JE, Sirsi SR, Dayton PA. In Vivo Demonstration of Cancer Molecular Imaging with Ultrasound Radiation Force and Buried-Ligand Microbubbles. Mol Imaging 2013. [DOI: 10.2310/7290.2013.00052] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Mark A. Borden
- From the Department of Mechanical Engineering, University of Colorado, Boulder, CO; Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC, University of North Carolina, Chapel Hill, NC
| | - Jason E. Streeter
- From the Department of Mechanical Engineering, University of Colorado, Boulder, CO; Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC, University of North Carolina, Chapel Hill, NC
| | - Shashank R. Sirsi
- From the Department of Mechanical Engineering, University of Colorado, Boulder, CO; Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC, University of North Carolina, Chapel Hill, NC
| | - Paul A. Dayton
- From the Department of Mechanical Engineering, University of Colorado, Boulder, CO; Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC, University of North Carolina, Chapel Hill, NC
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Liu C, Gao Z, Zeng J, Hou Y, Fang F, Li Y, Qiao R, Shen L, Lei H, Yang W, Gao M. Magnetic/upconversion fluorescent NaGdF4:Yb,Er nanoparticle-based dual-modal molecular probes for imaging tiny tumors in vivo. ACS NANO 2013; 7:7227-40. [PMID: 23879437 DOI: 10.1021/nn4030898] [Citation(s) in RCA: 229] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Detection of early malignant tumors remains clinically difficult; developing ultrasensitive imaging agents is therefore highly demanded. Owing to the unusual magnetic and optical properties associated with f-electrons, rare-earth elements are very suitable for creating functional materials potentially useful for tumor imaging. Nanometer-sized particles offer such a platform with which versatile unique properties of the rare-earth elements can be integrated. Yet the development of rare-earth nanoparticle-based tumor probes suitable for imaging tiny tumors in vivo remains difficult, which challenges not only the physical properties of the nanoparticles but also the rationality of the probe design. Here we report new approaches for size control synthesis of magnetic/upconversion fluorescent NaGdF4:Yb,Er nanocrystals and their applications for imaging tiny tumors in vivo. By independently varying F(-):Ln(3+) and Na(+):Ln(3+) ratios, the size and shape regulation mechanisms were investigated. By replacing the oleic acid ligand with PEG2000 bearing a maleimide group at one end and two phosphate groups at the other end, PEGylated NaGdF4:Yb,Er nanoparticles with optimized size and upconversion fluorescence were obtained. Accordingly, a dual-modality molecular tumor probe was prepared, as a proof of concept, by covalently attaching antitumor antibody to PEGylated NaGdF4:Yb,Er nanoparticles through a "click" reaction. Systematic investigations on tumor detections, through magnetic resonance imaging and upconversion fluorescence imaging, were carried out to image intraperitoneal tumors and subcutaneous tumors in vivo. Owing to the excellent properties of the molecular probes, tumors smaller than 2 mm was successfully imaged in vivo. In addition, pharmacokinetic studies on differently sized particles were performed to disclose the particle size dependent biodistributions and elimination pathways.
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Affiliation(s)
- Chunyan Liu
- Institute of Chemistry, Chinese Academy of Sciences, Bei Yi Jie 2, Zhong Guan Cun, Beijing 100190, China
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Zhou Y, Wang Z, Chen Y, Shen H, Luo Z, Li A, Wang Q, Ran H, Li P, Song W, Yang Z, Chen H, Wang Z, Lu G, Zheng Y. Microbubbles from gas-generating perfluorohexane nanoemulsions for targeted temperature-sensitive ultrasonography and synergistic HIFU ablation of tumors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:4123-4130. [PMID: 23788403 DOI: 10.1002/adma.201301655] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Indexed: 06/02/2023]
Abstract
A special "small to big" temperature-responsive phase-transformation strategy based on the "acoustic droplet vaporization (ADV)" mechanism is developed for efficient targeted ultrasonography and synergistic high intensity focused ultrasound (HIFU) cancer surgery by engineering targeted nanoemulsions, which is systematically evaluated and successfully demonstrated in vitro, ex vivo, and in vivo.
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Affiliation(s)
- Yang Zhou
- Institute of Ultrasound Imaging, Second Affiliated Hospital of Chongqing, Medical University, Chongqing, P. R. China
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Huang Y, Vykhodtseva NI, Hynynen K. Creating brain lesions with low-intensity focused ultrasound with microbubbles: a rat study at half a megahertz. ULTRASOUND IN MEDICINE & BIOLOGY 2013; 39:1420-8. [PMID: 23743099 PMCID: PMC4042243 DOI: 10.1016/j.ultrasmedbio.2013.03.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 02/21/2013] [Accepted: 03/05/2013] [Indexed: 05/07/2023]
Abstract
Low-intensity focused ultrasound was applied with microbubbles (Definity, Lantheus Medical Imaging, North Billerica, MA, USA; 0.02 mL/kg) to produce brain lesions in 50 rats at 558 kHz. Burst sonications (burst length: 10 ms; pulse repetition frequency: 1 Hz; total exposure: 5 min; acoustic power: 0.47-1.3 W) generated ischemic or hemorrhagic lesions at the focal volume revealed by both magnetic resonance imaging and histology. Shorter burst time (2 ms) or shorter sonication time (1 min) reduced the probability of lesion production. Longer pulses (200 ms, 500 ms and continuous wave) caused significant near-field damage. Using microbubbles with focused ultrasound significantly reduced acoustic power levels and, therefore, avoided skull heating issues and potentially can extend the treatable volume of transcranial focused ultrasound to brain tissues close to the skull.
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Affiliation(s)
- Yuexi Huang
- Sunnybrook Research Institute, Toronto, ON, Canada
| | - Natalia I. Vykhodtseva
- Department of Radiology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Kullervo Hynynen
- Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Correspondence to: K.H., Imaging Research, Rm S665B, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada. Kullervo Hynynen Phone: (416) 480-5717 Fax: (416) 480-5714
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Christ GJ, Saul JM, Furth ME, Andersson KE. The pharmacology of regenerative medicine. Pharmacol Rev 2013; 65:1091-133. [PMID: 23818131 DOI: 10.1124/pr.112.007393] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Regenerative medicine is a rapidly evolving multidisciplinary, translational research enterprise whose explicit purpose is to advance technologies for the repair and replacement of damaged cells, tissues, and organs. Scientific progress in the field has been steady and expectations for its robust clinical application continue to rise. The major thesis of this review is that the pharmacological sciences will contribute critically to the accelerated translational progress and clinical utility of regenerative medicine technologies. In 2007, we coined the phrase "regenerative pharmacology" to describe the enormous possibilities that could occur at the interface between pharmacology, regenerative medicine, and tissue engineering. The operational definition of regenerative pharmacology is "the application of pharmacological sciences to accelerate, optimize, and characterize (either in vitro or in vivo) the development, maturation, and function of bioengineered and regenerating tissues." As such, regenerative pharmacology seeks to cure disease through restoration of tissue/organ function. This strategy is distinct from standard pharmacotherapy, which is often limited to the amelioration of symptoms. Our goal here is to get pharmacologists more involved in this field of research by exposing them to the tools, opportunities, challenges, and interdisciplinary expertise that will be required to ensure awareness and galvanize involvement. To this end, we illustrate ways in which the pharmacological sciences can drive future innovations in regenerative medicine and tissue engineering and thus help to revolutionize the discovery of curative therapeutics. Hopefully, the broad foundational knowledge provided herein will spark sustained conversations among experts in diverse fields of scientific research to the benefit of all.
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Affiliation(s)
- George J Christ
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA.
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Garg S, Thomas AA, Borden MA. The effect of lipid monolayer in-plane rigidity on in vivo microbubble circulation persistence. Biomaterials 2013; 34:6862-70. [PMID: 23787108 DOI: 10.1016/j.biomaterials.2013.05.053] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 05/23/2013] [Indexed: 11/29/2022]
Abstract
The goal of this study was to increase in vivo microbubble circulation persistence for applications in medical imaging and targeted drug delivery. Our approach was to investigate the effect of lipid monolayer in-plane rigidity to reduce the rate of microbubble dissolution, while holding constant the microbubble size, concentration and surface architecture. We first estimated the impact of acyl chain length of the main diacyl phosphatidylcholine (PC) lipid and inter-lipid distance on the cohesive surface energy and, based on these results, we hypothesized that microbubble stability and in vivo ultrasound contrast persistence would increase monotonically with increasing acyl chain length. We therefore measured microbubble in vitro stability to dilution with and without ultrasound exposure, as well as in vivo ultrasound contrast persistence. All measurements showed a sharp rise in stability between DPPC (C16:0) and DSPC (C18:0), which correlates to the wrinkling transition, signaling the onset of significant surface shear and gas permeation resistance, observed in prior single-bubble dissolution studies. Further evidence for the effect of the wrinkling transition came from an in vitro and in vivo stability comparison of microbubbles coated with pure DPPC with those of lung surfactant extract. Microbubble stability against dilution without ultrasound and in vivo ultrasound contrast persistence showed a monotonic increase with acyl chain length from DSPC to DBPC (C22:0). However, we also observed that stability dropped precipitously for all measurements on further increasing lipid acyl chain length from DBPC to DLiPC (C24:0). This result suggests that hydrophobic mismatch between the main PC lipid and the lipopolymer emulsifier, DSPE-PEG5000, may drive a less stable surface microstructure. Overall, these results support our general hypothesis of the role of in-plane rigidity for increasing the lifetime of microbubble circulation.
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Affiliation(s)
- Sumit Garg
- Department of Mechanical Engineering, Materials Science and Engineering Program, University of Colorado, 1111 Engineering Drive, Boulder, CO 80309-0427, USA
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Sirsi SR, Borden MA. Advances in ultrasound mediated gene therapy using microbubble contrast agents. Am J Cancer Res 2012; 2:1208-22. [PMID: 23382777 PMCID: PMC3563148 DOI: 10.7150/thno.4306] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 07/01/2012] [Indexed: 12/19/2022] Open
Abstract
Microbubble ultrasound contrast agents have the potential to dramatically improve gene therapy treatments by enhancing the delivery of therapeutic DNA to malignant tissue. The physical response of microbubbles in an ultrasound field can mechanically perturb blood vessel walls and cell membranes, enhancing drug permeability into malignant tissue. In this review, we discuss literature that provided evidence of specific mechanisms that enhance in vivo gene delivery utilizing microbubble contrast agents, namely their ability to 1) improving cell membrane permeability, 2) modulate vascular permeability, and 3) enhance endocytotic uptake in cells. Additionally, we review novel microbubble vectors that are being developed in order to exploit these mechanisms and deliver higher gene payloads with greater target specificity. Finally, we discuss some future considerations that should be addressed in the development of next-generation microbubbles in order to improve in vivo microbubble gene delivery. Overall, microbubbles are rapidly gaining popularity as efficient gene carriers, and combined with their functionality as imaging contrast agents, they represent powerful theranostic tools for image guided gene therapy applications.
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