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Hussein M, Pasqua M, Pereira U, Benzoubir N, Duclos-Vallée JC, Dubart-Kupperschmitt A, Legallais C, Messina A. Microencapsulated Hepatocytes Differentiated from Human Induced Pluripotent Stem Cells: Optimizing 3D Culture for Tissue Engineering Applications. Cells 2023; 12:cells12060865. [PMID: 36980206 PMCID: PMC10047414 DOI: 10.3390/cells12060865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/14/2023] Open
Abstract
Liver cell therapy and in vitro models require functional human hepatocytes, the sources of which are considerably limited. Human induced pluripotent stem cells (hiPSCs) represent a promising and unlimited source of differentiated human hepatocytes. However, when obtained in two-dimensional (2D) cultures these hepatocytes are not fully mature and functional. As three-dimensional culture conditions offer advantageous strategies for differentiation, we describe here a combination of three-dimensional (3D) approaches enabling the successful differentiation of functional hepatocytes from hiPSCs by the encapsulation of hiPSC-derived hepatoblasts in alginate beads of preformed aggregates. The resulting encapsulated and differentiated hepatocytes (E-iHep-Orgs) displayed a high level of albumin synthesis associated with the disappearance of α-fetoprotein (AFP) synthesis, thus demonstrating that the E-iHep-Orgs had reached a high level of maturation, similar to that of adult hepatocytes. Gene expression analysis by RT-PCR and immunofluorescence confirmed this maturation. Further functional assessments demonstrated their enzymatic activities, including lactate and ammonia detoxification, as well as biotransformation activities of Phase I and Phase II enzymes. This study provides proof of concept regarding the benefits of combining three-dimensional techniques (guided aggregation and microencapsulation) with liver differentiation protocols as a robust approach to generate mature and functional hepatocytes that offer a permanent and unlimited source of hepatocytes. Based on these encouraging results, our combined conditions to produce mature hepatocytes from hiPSCs could be extended to liver tissue engineering and bioartificial liver (BAL) applications at the human scale for which large biomasses are mandatory.
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Affiliation(s)
- Marwa Hussein
- UMR_S 1193, INSERM/Université Paris Saclay, F-94800 Villejuif, France
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
| | - Mattia Pasqua
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
- UMR CNRS 7338 Biomechanics & Bioengineering, Université de Technologie de Compiègne, Sorbonne Universités, F-60203 Compiegne, France
| | - Ulysse Pereira
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
- UMR CNRS 7338 Biomechanics & Bioengineering, Université de Technologie de Compiègne, Sorbonne Universités, F-60203 Compiegne, France
| | - Nassima Benzoubir
- UMR_S 1193, INSERM/Université Paris Saclay, F-94800 Villejuif, France
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
| | - Jean-Charles Duclos-Vallée
- UMR_S 1193, INSERM/Université Paris Saclay, F-94800 Villejuif, France
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
| | - Anne Dubart-Kupperschmitt
- UMR_S 1193, INSERM/Université Paris Saclay, F-94800 Villejuif, France
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
| | - Cecile Legallais
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
- UMR CNRS 7338 Biomechanics & Bioengineering, Université de Technologie de Compiègne, Sorbonne Universités, F-60203 Compiegne, France
- Correspondence: (C.L.); (A.M.)
| | - Antonietta Messina
- UMR_S 1193, INSERM/Université Paris Saclay, F-94800 Villejuif, France
- Fédération Hospitalo-Universitaire (FHU) Hépatinov, F-94800 Villejuif, France
- Correspondence: (C.L.); (A.M.)
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Shah RA, Runge T, Ostertag TW, Tang S, Dziubla TD, Hilt JZ. Development of temperature-responsive polymeric gels with physical crosslinking due to intermolecular 𝜋-𝜋 interactions. POLYM INT 2022; 71:292-300. [PMID: 35695835 PMCID: PMC9173683 DOI: 10.1002/pi.6328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Poly(N-isopropylacrylamide) PNIPAAm was polymerized with co-monomers containing a biphenyl moiety to create a unique thermoresponsive physically crosslinked system due to the presence of pi-pi interactions between the biphenyl moieties. The biphenyl monomers used were 2-phenylphenol monoacrylate (2PPMA) and 4-phenylphenol monoacrylate (4PPMA). These monomers were utilized to synthesize a set of polymers with biphenyl monomer (2PPMA/4PPMA) content from 2.5 to 7.5 mole percent and with initiator concentrations from 0.1 and 1.0 weight percent. The resulting polymers were characterized by various techniques, such as gel permeation chromatography (GPC), swelling studies and mechanical testing. The decrease in the average molecular weight of the polymers due to the increase in the concentration of initiator was confirmed by GPC results. Swelling studies confirmed the expected temperature dependent swelling properties and explored the impact of the biphenyl comonomers. These studies indicated that with the increase in biphenyl comonomers, the physical crosslinking increases which leads to decrease in the swelling ratio. The results from the mechanical tests also depict the effect of the concentration of biphenyl comonomers. These physically crosslinked polymeric systems with their unique properties have potential applications spanning environmental remediation/sensing, biomedicine, etc.
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Affiliation(s)
- Rishabh A. Shah
- Superfund Research Center, University of Kentucky, Lexington, KY 40536, USA,Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - Tyler Runge
- Department of Physics and Engineering, Washington and Lee University, Lexington, VA 24450, USA
| | - Thomas W. Ostertag
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - Shuo Tang
- Superfund Research Center, University of Kentucky, Lexington, KY 40536, USA,Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - Thomas D. Dziubla
- Superfund Research Center, University of Kentucky, Lexington, KY 40536, USA,Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - J. Zach Hilt
- Superfund Research Center, University of Kentucky, Lexington, KY 40536, USA,Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA,Author to whom correspondence should be addressed,
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Selden C, Bundy J, Erro E, Puschmann E, Miller M, Kahn D, Hodgson H, Fuller B, Gonzalez-Molina J, Le Lay A, Gibbons S, Chalmers S, Modi S, Thomas A, Kilbride P, Isaacs A, Ginsburg R, Ilsley H, Thomson D, Chinnery G, Mankahla N, Loo L, Spearman CW. A clinical-scale BioArtificial Liver, developed for GMP, improved clinical parameters of liver function in porcine liver failure. Sci Rep 2017; 7:14518. [PMID: 29109530 PMCID: PMC5674071 DOI: 10.1038/s41598-017-15021-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 10/20/2017] [Indexed: 12/15/2022] Open
Abstract
Liver failure, whether arising directly from acute liver failure or from decompensated chronic liver disease is an increasing problem worldwide and results in many deaths. In the UK only 10% of individuals requiring a liver transplant receive one. Thus the need for alternative treatments is paramount. A BioArtificial Liver machine could temporarily replace the functions of the liver, buying time for the patient's liver to repair and regenerate. We have designed, implemented and tested a clinical-scale BioArtificial Liver machine containing a biomass derived from a hepatoblastoma cell-line cultured as three dimensional organoids, using a fluidised bed bioreactor, together with single-use bioprocessing equipment, with complete control of nutrient provision with feedback BioXpert recipe processes, and yielding good phenotypic liver functions. The methodology has been designed to meet specifications for GMP production, required for manufacture of advanced therapy medicinal products (ATMPs). In a porcine model of severe liver failure, damage was assured in all animals by surgical ischaemia in pigs with human sized livers (1.2-1.6 kg liver weights). The BioArtificial liver (UCLBAL) improved important prognostic clinical liver-related parameters, eg, a significant improvement in coagulation, reduction in vasopressor requirements, improvement in blood pH and in parameters of intracranial pressure (ICP) and oxygenation.
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Affiliation(s)
- Clare Selden
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom.
| | - James Bundy
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Eloy Erro
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Eva Puschmann
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Malcolm Miller
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Delawir Kahn
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Humphrey Hodgson
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Barry Fuller
- Dept. of Surgery, UCL Medical School, Royal Free Hospital, London, NW3 2QG, UK
| | - Jordi Gonzalez-Molina
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Aurelie Le Lay
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Stephanie Gibbons
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Sherri Chalmers
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Sunil Modi
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Amy Thomas
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Peter Kilbride
- UCL Institute for Liver and Digestive Health, UCL - Royal Free Hospital Campus, UCL Medical School, London, United Kingdom
| | - Agnes Isaacs
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Richard Ginsburg
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Helen Ilsley
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - David Thomson
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Galya Chinnery
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Ncedile Mankahla
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - Lizel Loo
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
| | - C Wendy Spearman
- Faculty of Health Sciences, University of Cape Town, Groote Schuur Hospital, Cape Town, South Africa
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Optimizing the fluidized bed bioreactor as an external bioartificial liver. Int J Artif Organs 2017; 40:196-203. [PMID: 28362045 DOI: 10.5301/ijao.5000567] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2017] [Indexed: 01/24/2023]
Abstract
BACKGROUND Our team previously designed and validated a new bioartificial liver (BAL) called Suppliver based on a Prismaflex™ device, including fluidized bed bioreactors hosting alginate-encapsulated hepatocytes. To ensure correct fluidization within the bioreactor, the beads need to become heavier with the addition of inert glass microspheres. METHODS In this study, we assessed the impact of this additional component on the bead production process, bed fluidization, mass transfer and the mechanical properties of the beads, as well as cell viability and basic metabolic function. RESULTS A concentration of 20 mg (1% v/v) of microspheres for 15-20 million cells per milliliter of alginate solution appears to be the best configuration. The filling ratio for the beads in the bioreactors can reach 60%. Four 250-mL bioreactors represent approximately 15% of the hepatocytes in a liver, which is a reasonable target for extracorporeal liver supply. CONCLUSIONS Increasing bead density clearly maintained the performances of the fluidized bed with plasma of different compositions, without any risk of release out of the bioreactor. A 1% (v/v)-concentration of microspheres in alginate solution did not result in any alteration of the mechanical or biological behavior. This concentration can thus be applied to the production of large-scale encapsulated biomass for further use of the Suppliver setup in human scale preclinical studies.
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Figaro S, Pereira U, Dumé AS, Rada H, Capone S, Bengrine A, Baze A, Rabenirina E, Semenzato N, Herpe YE, Faivre J, Dufresne M, Richert L, Duverlie G, Daujat-Chavanieu M, Saliba F, Pouchoulin D, Legallais C. SUPPLIVER: Bioartificial supply for liver failure. Ing Rech Biomed 2015. [DOI: 10.1016/j.irbm.2015.01.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Chen L, Zhang Y, Li S, Wang X, Li N, Wang Y, Guo X, Zhao S, Yu W, Sun G, Liu Y, Ma X. Effect of plasma components on the stability and permeability of microcapsule. J Biomed Mater Res A 2013; 102:2408-16. [PMID: 23946210 DOI: 10.1002/jbm.a.34907] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/11/2013] [Accepted: 08/05/2013] [Indexed: 01/05/2023]
Abstract
Immobilization of hepatocytes in microcapsules has been a potentially alternative methodology for bioartificial livers (BALs). Moreover, the stability and permeability are the key parameters of these microcapsules. However, these alginate-based microcapsules are unstable if the surrounding medium disrupts the ionic interactions between alginate and the polycation. As hundreds of components are included in human plasma, the stability and permeability in plasma of microcapsules need to be sufficiently investigated. In the present study, the stability of three kinds of alginate-based microcapsules was evaluated when they were immersed in plasma. Our results showed that stability of alginate-α-poly (L-lysine)-alginate (α-APA) microcapsules was well maintained, better than those of alginate-ε-poly (L-lysine)-alginate (ε-APA) and alginate-chitosan-alginate (ACA) microcapsules. Also, factors affecting the stability of microcapsules in plasma were analyzed and it showed that heparin was the key factor that affected the stability of α-APA microcapsules, whereas heparin and low molecular electrolytes such as HCO3(-) and H2 PO4(-)/HPO4(2-) were the factors to ε-APA and ACA microcapsules. In addition, the permeability evaluation showed no decrease in permeability of microcapsules after incubation in plasma. Our study might provide a foundation for the selection and modification of materials for microcapsule-based BAL devices.
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Affiliation(s)
- Li Chen
- Laboratory of Biomedical Material Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
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7
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Capone SH, Dufresne M, Rechel M, Fleury MJ, Salsac AV, Paullier P, Daujat-Chavanieu M, Legallais C. Impact of alginate composition: from bead mechanical properties to encapsulated HepG2/C3A cell activities for in vivo implantation. PLoS One 2013; 8:e62032. [PMID: 23637958 PMCID: PMC3636232 DOI: 10.1371/journal.pone.0062032] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 03/18/2013] [Indexed: 12/14/2022] Open
Abstract
Recently, interest has focused on hepatocytes' implantation to provide end stage liver failure patients with a temporary support until spontaneous recovery or a suitable donor becomes available. To avoid cell damage and use of an immunosuppressive treatment, hepatic cells could be implanted after encapsulation in a porous biomaterial of bead or capsule shape. The aim of this study was to compare the production and the physical properties of the beads, together with some hepatic cell functions, resulting from the use of different material combinations for cell microencapsulation: alginate alone or combined with type I collagen with or without poly-L-lysine and alginate coatings. Collagen and poly-L-lysine increased the bead mechanical resistance but lowered the mass transfer kinetics of vitamin B12. Proliferation of encapsulated HepG2/C3A cells was shown to be improved in alginate-collagen beads. Finally, when the beads were subcutaneously implanted in mice, the inflammatory response was reduced in the case of alginate mixed with collagen. This in vitro and in vivo study clearly outlines, based on a systematic comparison, the necessity of compromising between material physical properties (mechanical stability and porosity) and cell behavior (viability, proliferation, functionalities) to define optima hepatic cell microencapsulation conditions before implantation.
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Affiliation(s)
- Stephanie H Capone
- UMR CNRS 7338, Laboratory of Biomechanics and Bioengineering, University of Technology, Compiegne, France
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Erro E, Bundy J, Massie I, Chalmers SA, Gautier A, Gerontas S, Hoare M, Sharratt P, Choudhury S, Lubowiecki M, Llewellyn I, Legallais C, Fuller B, Hodgson H, Selden C. Bioengineering the liver: scale-up and cool chain delivery of the liver cell biomass for clinical targeting in a bioartificial liver support system. Biores Open Access 2013; 2:1-11. [PMID: 23514704 PMCID: PMC3569957 DOI: 10.1089/biores.2012.0286] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Acute liver failure has a high mortality unless patients receive a liver transplant; however, there are insufficient donor organs to meet the clinical need. The liver may rapidly recover from acute injury by hepatic cell regeneration given time. A bioartificial liver machine can provide temporary liver support to enable such regeneration to occur. We developed a bioartificial liver machine using human-derived liver cells encapsulated in alginate, cultured in a fluidized bed bioreactor to a level of function suitable for clinical use (performance competence). HepG2 cells were encapsulated in alginate using a JetCutter to produce ∼500 μm spherical beads containing cells at ∼1.75 million cells/mL beads. Within the beads, encapsulated cells proliferated to form compact cell spheroids (AELS) with good cell-to-cell contact and cell function, that were analyzed functionally and by gene expression at mRNA and protein levels. We established a methodology to enable a ∼34-fold increase in cell density within the AELS over 11-13 days, maintaining cell viability. Optimized nutrient and oxygen provision were numerically modeled and tested experimentally, achieving a cell density at harvest of >45 million cells/mL beads; >5×10(10) cells were produced in 1100 mL of beads. This process is scalable to human size ([0.7-1]×10(11)). A short-term storage protocol at ambient temperature was established, enabling transport from laboratory to bedside over 48 h, appropriate for clinical translation of a manufactured bioartificial liver machine.
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Affiliation(s)
- Eloy Erro
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - James Bundy
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Isobel Massie
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Sherri-Ann Chalmers
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Aude Gautier
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Spyridon Gerontas
- The Advanced Center for Biochemical Engineering, Department of Biochemical Engineering; University College London, London, United Kingdom
| | - Mike Hoare
- The Advanced Center for Biochemical Engineering, Department of Biochemical Engineering; University College London, London, United Kingdom
| | - Peter Sharratt
- PNAC Facility, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Sarah Choudhury
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Marcin Lubowiecki
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Ian Llewellyn
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Cécile Legallais
- CNRS UMR 6600 Biomechanics and Bioengineering, University of Technology of Compiègne, Compiègne, France
| | - Barry Fuller
- Cell, Tissue & Organ Preservation Unit, University Department of Surgery, UCL Medical School, Royal Free Hospital Campus, London, United Kingdom
| | - Humphrey Hodgson
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
| | - Clare Selden
- Liver Group, UCL Institute of Liver & Digestive Health, London, United Kingdom
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Zhang L, Salsac AV. Can sonication enhance release from liquid-core capsules with a hydrogel membrane? J Colloid Interface Sci 2011; 368:648-54. [PMID: 22196351 DOI: 10.1016/j.jcis.2011.11.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 11/16/2011] [Accepted: 11/17/2011] [Indexed: 11/24/2022]
Abstract
The objective is to investigate the influence of sonication on the mechanical and release properties of hydrogel capsules. A new fabrication process is developed to fabricate millimetric capsules made of a highly-viscous liquid core protected by a thin hyperelastic alginate membrane. At high intensities and/or long exposure times, sonication can lead to the capsule rupture, because it induces fatigue in the membrane. Below the breakup threshold, no remnant effect of sonication is, however, measured on the capsule mechanical properties. The release is studied by sonicating capsules filled with blue dextran suspended in an aqueous solution. The mass release that results from sonication is found to be proportional to the sonication duration time and pressure wave amplitude. A possible physical interpretation is that the acoustic streaming flow induced by the ultrasonic wave enhances convection in the vicinity of the capsule membrane and thus mass release. We have finally quantified the passive release subsequent to low-intensity sonications: it is on average identical to the one measured on non-sonicated capsules. Overall the membrane therefore recovers its physical and mechanical properties after sonication. If sonication leads to an increase in porosity of the capsule membrane, the increase is temporary and reverses back at the end of the ultrasonic stimulation.
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Affiliation(s)
- Liguo Zhang
- Laboratoire Biomécanique et Bioingénierie (UMR CNRS 6600), Université de Technologie de Compiègne, 60205 Compiègne, France
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