1
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Gale L, Panieraki A, Mahmoodi N, Crolla JP, Thomas-Seale LEJ. The design and characterisation of sinusoidal toolpaths using sub-zero bioprinting of polyvinyl alcohol. J Mech Behav Biomed Mater 2024; 152:106402. [PMID: 38342023 DOI: 10.1016/j.jmbbm.2024.106402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 01/10/2024] [Accepted: 01/11/2024] [Indexed: 02/13/2024]
Abstract
Sub-zero (°C) additive manufacturing (AM) systems present a promising solution for the fabrication of hydrogel structures with complex external geometry or a heterogeneous internal structure. Polyvinyl alcohol cryogels (PVA-C) are promising tissue-mimicking materials, with mechanical properties that can be designed to satisfy a wide variety of soft tissues. However, the design of more complex mechanical properties into additively manufactured PVA-C samples, which can be enabled using the toolpath, is a largely unstudied area. This research project will investigate the effect of toolpath variation on the elastic and viscoelastic properties of PVA-C samples fabricated using a sinusoidal toolpath. Samples were fabricated using parametric variation of a sinusoidal toolpath, whilst retaining the same overall cross-sectional area, using a sub-zero AM system. To mechanically characterise the samples, they were tested under tension in uniaxial ramp tests, and through dynamic mechanical analysis (DMA). The elastic and viscoelastic moduli of the samples are presented. No correlations between the parametric variation of the design and the Young's modulus were observed. Analysis of the data shows high intra-sample repeatability, demonstrated robust testing protocols, and variable inter-sample repeatability, indicating differences in the printability and consistency of fabrication between sample sets. DMA of the wavelength samples, show a frequency-dependent loss moduli. The storage modulus demonstrates frequency independence, and a large increase in magnitude as the sample increases to 3 wavelengths.
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Affiliation(s)
- L Gale
- Department of Mechanical Engineering, School of Engineering, University of Birmingham, UK
| | - A Panieraki
- Department of Mechanical Engineering, School of Engineering, University of Birmingham, UK
| | - N Mahmoodi
- Department of Mechanical Engineering, School of Engineering, University of Birmingham, UK
| | - J P Crolla
- Department of Mechanical Engineering, School of Engineering, University of Birmingham, UK
| | - L E J Thomas-Seale
- Department of Mechanical Engineering, School of Engineering, University of Birmingham, UK.
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2
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Su YC, Chang Y, Lee WC, Wang JH, Narita T, Takeno H, Syu JY, Jou IM, Hsieh WC. Study of chondrogenesis of umbilical cord mesenchymal stem cells in curdlan- poly(vinyl alcohol) composite hydrogels and its mechanical properties of freezing-thawing treatments. Int J Biol Macromol 2024; 265:130792. [PMID: 38479670 DOI: 10.1016/j.ijbiomac.2024.130792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 03/04/2024] [Accepted: 03/09/2024] [Indexed: 03/24/2024]
Abstract
The curdlan gel is a natural material produced by bacteria. It utilizes chemical cross-linking reactions to form a 3D porous composite hydrogel, increasing its porosity and water content, and improving its mechanical properties. It can be used in tissue repair and regenerative medicine. Curdlan-Poly(vinyl alcohol) (PVA) composite hydrogel can rapidly swell within 1 min due to its porous structure. Compression tests confirmed that it still maintains its original mechanical strength, even after five repeated freeze-thaw (FT) processes, making it suitable for long-term cryopreservation. The purpose of this study is to transplant umbilical cord mesenchymal stem cells (UC-MSCs) on Curdlan-PVA composite hydrogel and observe the chondrocytes on the material. The results of using 4',6-diamidino-2-phenylindole (DAPI), hematoxylin and eosin (H&E), calcein-acetoxymethyl ester (calcein AM), and Collagen type II-Fluorescein isothiocyanate (FITC) staining, confirmed that UC-MSCs can attach and differentiate into chondrocytes on 3D Curdlan-PVA composite hydrogel.
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Affiliation(s)
- Yu-Chieh Su
- Division of Hematology-Oncology, Department of Internal Medicine, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan; School of Medicine, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Yu Chang
- Department of Obstetrics and Gynecology, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan; School of Medicine for International Students, College of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Wei-Chang Lee
- Division of Hematology-Oncology, Department of Internal Medicine, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Jhih-Han Wang
- Department of Medical Science and Biotechnology, I-Shou University, Kaohsiung 824005, Taiwan
| | - Takumi Narita
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Gunma 376-8515, Japan
| | - Hiroyuki Takeno
- Division of Molecular Science, Graduate School of Science and Technology, Gunma University, Gunma 376-8515, Japan; Gunma University Center for Food Science and Wellness (GUCFW), Gunma 376-8515, Japan
| | - Jie-Yu Syu
- Department of Medical Science and Biotechnology, I-Shou University, Kaohsiung 824005, Taiwan
| | - I-Ming Jou
- Department of Orthopedics, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Wen-Chuan Hsieh
- Department of Medical Science and Biotechnology, I-Shou University, Kaohsiung 824005, Taiwan.
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3
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D’Altri G, Yeasmin L, Di Matteo V, Scurti S, Giovagnoli A, Di Filippo MF, Gualandi I, Cassani MC, Caretti D, Panzavolta S, Scavetta E, Rea M, Ballarin B. Preparation and Characterization of Self-Healing PVA-H 2SO 4 Hydrogel for Flexible Energy Storage. ACS OMEGA 2024; 9:6391-6402. [PMID: 38371784 PMCID: PMC10870281 DOI: 10.1021/acsomega.3c05392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 01/11/2024] [Accepted: 01/15/2024] [Indexed: 02/20/2024]
Abstract
In the past decade, hydrogels have attracted growing interest for emerging applications in flexible electronic devices, human-machine interactions, energy supply, or energy storage. Developing a multifunctional gel architecture with superior ionic conductivity and good mechanical flexibility is a bottleneck to overcome. Herein, poly(vinyl alcohol)/sulfuric acid (PVA-H2SO4) hydrogels were prepared via a freeze-thaw method. With the aim of tuning the formulation in view of a possible application in energy storage, the effects of different combinations in terms of the molecular weight (MW) of PVA and PVA-H2SO4 weight ratio were investigated. Moreover, exploiting the self-healing properties of these hydrogels and the easy possibility of functionalizing them, i.e., introducing a conducting polymer such as poly(2-acrylamido-2-methyl-1-propane) sulfonic acid doped polyaniline (PANI_PAMPSA), a sandwiched all-in-one double-layer hydrogel (electrode/electrolyte configuration) was prepared (PVA-H2SO4-PANI_PAMPSA/PVA-H2SO4). Results showed that the water content is independent of the PVA amount and MW; the polymer concentration has a significant effect on the formation of crystalline domains and therefore on swelling degree, whereas the cross-linking degree depends on the MW. The PVA MW has the maximum effect on the swelling percentage normalized with respect to the polymer fraction and the tensile properties of the hydrogel. The assembled all-in-one electrode/electrolyte shows promising ionic conductivity (439.7 mS cm-1) and specific capacitance performance (0.297 mF cm-2 at a current density of 0.025 mA cm-2), as well as excellent flexibility and considerable self-healing properties. These results will promote the development of self-healing symmetrical supercapacitors for storage devices in wearable electronics.
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Affiliation(s)
- Giada D’Altri
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
| | - Lamyea Yeasmin
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Politecnico
di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino, Italy
| | - Valentina Di Matteo
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
| | - Stefano Scurti
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
| | - Angelica Giovagnoli
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
| | | | - Isacco Gualandi
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Center
for Industrial Research−Advanced Applications in Mechanical
Engineering and Materials Technology—CIRI MAM, University of Bologna, Viale del Risorgimento 2, I-40136 Bologna, Italy
| | - Maria Cristina Cassani
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Center
for Industrial Research−Advanced Applications in Mechanical
Engineering and Materials Technology—CIRI MAM, University of Bologna, Viale del Risorgimento 2, I-40136 Bologna, Italy
- Consorzio
INSTM, Via G. Giusti,
9, 50121 Firenze, Italy
| | - Daniele Caretti
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Center
for Industrial Research−Advanced Applications in Mechanical
Engineering and Materials Technology—CIRI MAM, University of Bologna, Viale del Risorgimento 2, I-40136 Bologna, Italy
| | - Silvia Panzavolta
- Department
of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - Erika Scavetta
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Consorzio
INSTM, Via G. Giusti,
9, 50121 Firenze, Italy
| | - Mariangela Rea
- Department
of Chemistry “Giacomo Ciamician”, University of Bologna, Via Selmi 2, I-40126 Bologna, Italy
| | - Barbara Ballarin
- Department
of Industrial Chemistry “Toso Montanari”, University of Bologna, Via Risorgimento 4, I-40136 Bologna, Italy
- Center
for Industrial Research−Advanced Applications in Mechanical
Engineering and Materials Technology—CIRI MAM, University of Bologna, Viale del Risorgimento 2, I-40136 Bologna, Italy
- Center
for Industrial Research−Fonti Rinnovabili, Ambiente, Mare e
Energia—CIRI FRAME, University of
Bologna, Viale del Risorgimento 2, I-40136 Bologna, Italy
- Consorzio
INSTM, Via G. Giusti,
9, 50121 Firenze, Italy
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4
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Zhong Y, Zhang Y, Lu B, Deng Z, Zhang Z, Wang Q, Zhang J. Hydrogel Loaded with Components for Therapeutic Applications in Hypertrophic Scars and Keloids. Int J Nanomedicine 2024; 19:883-899. [PMID: 38293605 PMCID: PMC10824614 DOI: 10.2147/ijn.s448667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/12/2024] [Indexed: 02/01/2024] Open
Abstract
Hypertrophic scars and keloids are common fibroproliferative diseases following injury. Patients with pathologic scars suffer from impaired quality of life and psychological health due to appearance disfiguration, itch, pain, and movement disorders. Recently, the advancement of hydrogels in biomedical fields has brought a variety of novel materials, methods and therapeutic targets for treating hypertrophic scars and keloids, which exhibit broad prospects. This review has summarized current research on hydrogels and loaded components used in preventing and treating hypertrophic scars and keloids. These hydrogels attenuate keloid and hypertrophic scar formation and progression by loading organic chemicals, drugs, or bioactive molecules (such as growth factors, genes, proteins/peptides, and stem cells/exosomes). Among them, smart hydrogels (a very promising method for loading many types of bioactive components) are currently favoured by researchers. In addition, combining hydrogels and current therapy (such as laser or radiation therapy, etc.) could improve the treatment of hypertrophic scars and keloids. Then, the difficulties and limitations of the current research and possible suggestions for improvement are listed. Moreover, we also propose novel strategies for facilitating the construction of target multifunctional hydrogels in the future.
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Affiliation(s)
- Yixiu Zhong
- Department of Dermatology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China
| | - Youfan Zhang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Beibei Lu
- Department of Dermatology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China
| | - Zhenjun Deng
- Department of Dermatology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China
| | - Zhiwen Zhang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Qi Wang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, People’s Republic of China
| | - Jianglin Zhang
- Department of Dermatology, Shenzhen People’s Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, Guangdong, People’s Republic of China
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5
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Schröter F, Kühnel RU, Hartrumpf M, Ostovar R, Albes JM. Progress on a Novel, 3D-Printable Heart Valve Prosthesis. Polymers (Basel) 2023; 15:4413. [PMID: 38006137 PMCID: PMC10674413 DOI: 10.3390/polym15224413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/10/2023] [Accepted: 11/11/2023] [Indexed: 11/26/2023] Open
Abstract
(1) Background: Polymeric heart valves are prostheses constructed out of flexible, synthetic materials to combine the advantageous hemodynamics of biological valves with the longevity of mechanical valves. This idea from the early days of heart valve prosthetics has experienced a renaissance in recent years due to advances in polymer science. Here, we present progress on a novel, 3D-printable aortic valve prosthesis, the TIPI valve, removing the foldable metal leaflet restrictor structure in its center. Our aim is to create a competitive alternative to current valve prostheses made from flexible polymers. (2) Methods: Three-dimensional (3D) prototypes were designed and subsequently printed in silicone. Hemodynamic performance was measured with an HKP 2.0 hemodynamic testing device using an aortic valve bioprosthesis (BP), a mechanical prosthesis (MP), and the previously published prototype (TIPI 2.2) as benchmarks. (3) Results: The latest prototype (TIPI 3.4) showed improved performance in terms of regurgitation fraction (TIPI 3.4: 15.2 ± 3.7%, TIPI 2.2: 36.6 ± 5.0%, BP: 8.8 ± 0.3%, MP: 13.2 ± 0.7%), systolic pressure gradient (TIPI 3.4: 11.0 ± 2.7 mmHg, TIPI 2.2: 12.8 ± 2.2 mmHg, BP: 8.2 ± 0.9 mmHg, MP: 10.5 ± 0.6 mmHg), and effective orifice area (EOA, TIPI 3.4: 1.39 cm2, TIPI 2.2: 1.28 cm2, BP: 1.58 cm2, MP: 1.38 cm2), which was equivalent to currently used aortic valve prostheses. (4) Conclusions: Removal of the central restrictor structure alleviated previous concerns about its potential thrombogenicity and significantly increased the area of unobstructed opening. The prototypes showed unidirectional leaflet movement and very promising performance characteristics within our testing setup. The resulting simplicity of the shape compared to other approaches for polymeric heart valves could be suitable not only for 3D printing, but also for fast and easy mass production using molds and modern, highly biocompatible polymers.
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Affiliation(s)
- Filip Schröter
- Department of Cardiovascular Surgery, Heart Center Brandenburg, Brandenburg Medical School Theodor Fontane, 14770 Brandenburg an der Havel, Germany; (R.-U.K.); (M.H.); (R.O.); (J.M.A.)
- Faculty of Health Sciences Brandenburg, 14476 Potsdam, Germany
| | - Ralf-Uwe Kühnel
- Department of Cardiovascular Surgery, Heart Center Brandenburg, Brandenburg Medical School Theodor Fontane, 14770 Brandenburg an der Havel, Germany; (R.-U.K.); (M.H.); (R.O.); (J.M.A.)
| | - Martin Hartrumpf
- Department of Cardiovascular Surgery, Heart Center Brandenburg, Brandenburg Medical School Theodor Fontane, 14770 Brandenburg an der Havel, Germany; (R.-U.K.); (M.H.); (R.O.); (J.M.A.)
| | - Roya Ostovar
- Department of Cardiovascular Surgery, Heart Center Brandenburg, Brandenburg Medical School Theodor Fontane, 14770 Brandenburg an der Havel, Germany; (R.-U.K.); (M.H.); (R.O.); (J.M.A.)
| | - Johannes Maximilian Albes
- Department of Cardiovascular Surgery, Heart Center Brandenburg, Brandenburg Medical School Theodor Fontane, 14770 Brandenburg an der Havel, Germany; (R.-U.K.); (M.H.); (R.O.); (J.M.A.)
- Faculty of Health Sciences Brandenburg, 14476 Potsdam, Germany
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6
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Otulakowski Ł, Klama-Baryła A, Celny A, Kasprów M, Hercog A, Godzierz M, Sitkowska A, Kadłubowski S, Jaworska M, Chmielik E, Trzebicka B, Utrata-Wesołek A. Laminar Biomaterial Composite of PVA Cryogel with Amnion as Potential Wound Dressing. Polymers (Basel) 2023; 15:2955. [PMID: 37447600 DOI: 10.3390/polym15132955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/15/2023] Open
Abstract
Gel dressings, composed of polymers both natural and synthetic, are successfully used in the treatment of burn wounds. They protect the burn wound site against adverse external factors, ensure an adequate level of tissue hydration, have soothing and pain-relieving properties, and also support the healing process and reduce the risk of pathological scars. Another promising material that can be used in the wound-healing process is an amnion membrane. Due to its valuable properties such as protecting the body against bacterial infections and permeability to nutrition, it has found usage in different brands of medicine. In this work, we have combined the beneficial properties of hydrogels and amnion in order to make the laminar dressing that may serve for wound healing. For that purpose, the physically crosslinked cryogel of poly(vinyl alcohol) (PVA) was covered with an amnion membrane. Subsequently, gamma irradiation was performed, leading to the simultaneous internal crosslinking of the hydrogel, its permanent bonding with the amnion, and dressing sterilization. The physicochemical properties of the dressing including gel fraction, swelling, and hardness were studied. Biological tests such as the MTT assay, antimicrobial activity, and histopathological examination confirmed that the obtained material constituted a promising candidate for further, more in-depth studies aiming at wound dressing application.
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Affiliation(s)
- Łukasz Otulakowski
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Agnieszka Klama-Baryła
- Dr. Stanislaw Sakiel Center for Burn Treatment, 2 Jana Pawla II St., 41-100 Siemianowice Śląskie, Poland
| | - Anna Celny
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Maciej Kasprów
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Anna Hercog
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Marcin Godzierz
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Anna Sitkowska
- Dr. Stanislaw Sakiel Center for Burn Treatment, 2 Jana Pawla II St., 41-100 Siemianowice Śląskie, Poland
| | - Sławomir Kadłubowski
- Institute of Applied Radiation Chemistry, Chemistry Faculty, Lodz University of Technology, Wróblewskiego 15, 90-924 Łódź, Poland
| | - Magdalena Jaworska
- Tumor Pathology Department, Maria Skłodowska-Curie National Research Institute of Oncology Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland
| | - Ewa Chmielik
- Tumor Pathology Department, Maria Skłodowska-Curie National Research Institute of Oncology Gliwice Branch, Wybrzeże Armii Krajowej 15, 44-102 Gliwice, Poland
| | - Barbara Trzebicka
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
| | - Alicja Utrata-Wesołek
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819 Zabrze, Poland
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7
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Nathan KG, Genasan K, Kamarul T. Polyvinyl Alcohol-Chitosan Scaffold for Tissue Engineering and Regenerative Medicine Application: A Review. Mar Drugs 2023; 21:md21050304. [PMID: 37233498 DOI: 10.3390/md21050304] [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] [Received: 03/31/2023] [Revised: 04/23/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023] Open
Abstract
Tissue engineering and regenerative medicine (TERM) holds great promise for addressing the growing need for innovative therapies to treat disease conditions. To achieve this, TERM relies on various strategies and techniques. The most prominent strategy is the development of a scaffold. Polyvinyl alcohol-chitosan (PVA-CS) scaffold emerged as a promising material in this field due to its biocompatibility, versatility, and ability to support cell growth and tissue regeneration. Preclinical studies showed that the PVA-CS scaffold can be fabricated and tailored to fit the specific needs of different tissues and organs. Additionally, PVA-CS can be combined with other materials and technologies to enhance its regenerative capabilities. Furthermore, PVA-CS represents a promising therapeutic solution for developing new and innovative TERM therapies. Therefore, in this review, we summarized the potential role and functions of PVA-CS in TERM applications.
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Affiliation(s)
- Kavitha Ganesan Nathan
- Department of Orthopedic Surgery, Faculty of Medicine, University Malaya, Kuala Lumpur 50603, Malaysia
| | - Krishnamurithy Genasan
- Department of Physiology, Faculty of Medicine, University Malaya, Kuala Lumpur 50603, Malaysia
| | - Tunku Kamarul
- Department of Orthopedic Surgery, Faculty of Medicine, University Malaya, Kuala Lumpur 50603, Malaysia
- Advanced Medical and Dental Institute (AMDI), University Sains Malaysia, Bertam, Kepala Batas 13200, Malaysia
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8
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Rezvova MA, Klyshnikov KY, Gritskevich AA, Ovcharenko EA. Polymeric Heart Valves Will Displace Mechanical and Tissue Heart Valves: A New Era for the Medical Devices. Int J Mol Sci 2023; 24:ijms24043963. [PMID: 36835389 PMCID: PMC9967268 DOI: 10.3390/ijms24043963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
The development of a novel artificial heart valve with outstanding durability and safety has remained a challenge since the first mechanical heart valve entered the market 65 years ago. Recent progress in high-molecular compounds opened new horizons in overcoming major drawbacks of mechanical and tissue heart valves (dysfunction and failure, tissue degradation, calcification, high immunogenic potential, and high risk of thrombosis), providing new insights into the development of an ideal artificial heart valve. Polymeric heart valves can best mimic the tissue-level mechanical behavior of the native valves. This review summarizes the evolution of polymeric heart valves and the state-of-the-art approaches to their development, fabrication, and manufacturing. The review discusses the biocompatibility and durability testing of previously investigated polymeric materials and presents the most recent developments, including the first human clinical trials of LifePolymer. New promising functional polymers, nanocomposite biomaterials, and valve designs are discussed in terms of their potential application in the development of an ideal polymeric heart valve. The superiority and inferiority of nanocomposite and hybrid materials to non-modified polymers are reported. The review proposes several concepts potentially suitable to address the above-mentioned challenges arising in the R&D of polymeric heart valves from the properties, structure, and surface of polymeric materials. Additive manufacturing, nanotechnology, anisotropy control, machine learning, and advanced modeling tools have given the green light to set new directions for polymeric heart valves.
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Affiliation(s)
- Maria A. Rezvova
- Research Institute for Complex Issues of Cardiovascular Diseases, 650002 Kemerovo, Russia
| | - Kirill Y. Klyshnikov
- Research Institute for Complex Issues of Cardiovascular Diseases, 650002 Kemerovo, Russia
| | | | - Evgeny A. Ovcharenko
- Research Institute for Complex Issues of Cardiovascular Diseases, 650002 Kemerovo, Russia
- Correspondence:
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9
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Jing FY, Zhang YQ. Unidirectional Nanopore Dehydration Induces an Anisotropic Polyvinyl Alcohol Hydrogel Membrane with Enhanced Mechanical Properties. Gels 2022; 8:gels8120803. [PMID: 36547327 PMCID: PMC9778426 DOI: 10.3390/gels8120803] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
As a biocompatible, degradable polymer material, polyvinyl alcohol (PVA) can have a wide range of applications in the biomedical field. PVA aqueous solutions at room temperature can be cast into very thin films with poor mechanical strength via water evaporation. Here, we describe a novel dehydration method, unidirectional nanopore dehydration (UND). The UND method was used to directly dehydrate a PVA aqueous solution to form a water-stable, anisotropic, and mechanically robust PVA hydrogel membrane (PVAHM), whose tensile strength, elongation at break, and swelling ratio reached values of up to ~2.95 MPa, ~350%, and ~350%, respectively. The film itself exhibited an oriented arrangement of porous network structures with an average pore size of ~1.0 μm. At 70 °C, the PVAHMs formed were even more mechanically robust, with a tensile strength and elongation at break of 10.5 MPa and 891%, almost 3.5 times and 2 times greater than the PVAHM prepared at 25 °C, respectively. The processing temperature affects the velocity at which the water molecules flow unidirectionally through the nanopores, and could, thus, alter the overall transformation of the PVA chains into a physically crosslinked 3D network. Therefore, the temperature setting during UND can control the mechanical properties of the hydrogel membrane to meet the requirements of various biomaterial applications. These results show that the UND can induce the ordered rearrangement of PVA molecular chains, forming a PVAHM with superior mechanical properties and exhibiting a greater number of stronger hydrogen bonds. Therefore, the novel dehydration mode not only induces the formation of a mechanically robust and anisotropic PVA hydrogel membrane with a porous network structure and an average pore size of ~1.0 μm, but also greatly enhances the mechanical properties by increasing the temperature. It may be applied for the processing of water-soluble polymers, including proteins, as novel functional materials.
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10
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Ma Y, Ma A, Luo T, Xiao S, Zhou H. Fabrication of anisotropic nanocomposite hydrogels by magnetic field‐induced orientation for mimicking cardiac tissue. J Appl Polym Sci 2022. [DOI: 10.1002/app.53248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Yanzhuo Ma
- School of Materials and Chemical Engineering Xi'an Technological University Xi'an China
| | - Aijie Ma
- School of Materials and Chemical Engineering Xi'an Technological University Xi'an China
| | - Tao Luo
- School of Materials and Chemical Engineering Xi'an Technological University Xi'an China
| | - Siyu Xiao
- School of Materials and Chemical Engineering Xi'an Technological University Xi'an China
| | - Hongwei Zhou
- School of Materials and Chemical Engineering Xi'an Technological University Xi'an China
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Cross-evaluation of stiffness measurement methods for hydrogels. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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12
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Zhao J, Qian J, Luo J, Huang M, Yan W, Zhang J. Application of Ag@SiO 2 nanoparticles within PVA to reduce growth of E. coli and S. aureus in beef patties. J Food Sci 2022; 87:4569-4579. [PMID: 36065890 DOI: 10.1111/1750-3841.16292] [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] [Received: 05/26/2021] [Revised: 07/18/2022] [Accepted: 07/23/2022] [Indexed: 11/29/2022]
Abstract
To overcome defects of polyvinyl alcohol (PVA) and expand its applications in food preservation, PVA/Ag@SiO2 nanocomposite films were prepared using the solution intercalation film-casting method. Transmission electron microscopy, X-ray diffraction, and UV-visible absorption spectra were applied to confirm the synthesis of the nanoparticles (NPs). Effects of Ag@SiO2 NPs on physicochemical characteristics of films like viscosity, swelling ratio, tensile strength, elongation at break, as well as antibacterial activity were also evaluated. Results indicate that Ag@SiO2 NPs could be synthesized successfully, and the increasing concentration of Ag@SiO2 NPs led to the decrease in viscosity and the swelling ratio of the PVA/Ag@SiO2 NPs nanocomposite films. PVA/Ag@SiO2 nanocomposite films exhibited increased tensile strength and strong antibacterial activity against Escherichia coli and Staphylococcus aureus. The films had higher antibacterial activity toward E. coli compared with S. aureus. Beef patties were applied to verify the practicality of PVA/Ag@SiO2 films. PVA/Ag@SiO2 NPs nanocomposite films act as an active food packaging system showing great potential in retaining food safety and prolonging the shelf-life of packaged foods. PRACTICAL APPLICATION: During the storage of fresh meat, the microbial count on the meat surface increased with increasing storage time; meat proteins could be broken down by microorganisms, causing the tissue structure to be destroyed, leading to loose muscle fibers and loss of nutrient-containing juices. In this paper, by improving the PVA film, a new antibacterial membrane was prepared, which can be used for fresh meat sold in supermarkets, as a lining at the bottom of the meat or directly covering the meat. The method can significantly decrease the number of microorganisms and extend the shelf-life of fresh meat.
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Affiliation(s)
- Jianying Zhao
- College of Tea and Food Technology, Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu, China
| | - Jing Qian
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Ji Luo
- College of Life Science, Anhui Normal University, Wuhu, Anhui, China
| | - Mingming Huang
- College of Food Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, China
| | - Wenjing Yan
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Jianhao Zhang
- National Center of Meat Quality and Safety Control, Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China
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13
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Ho TC, Chang CC, Chan HP, Chung TW, Shu CW, Chuang KP, Duh TH, Yang MH, Tyan YC. Hydrogels: Properties and Applications in Biomedicine. Molecules 2022; 27:2902. [PMID: 35566251 PMCID: PMC9104731 DOI: 10.3390/molecules27092902] [Citation(s) in RCA: 149] [Impact Index Per Article: 74.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/17/2022] [Accepted: 04/20/2022] [Indexed: 12/19/2022] Open
Abstract
Hydrogels are crosslinked polymer chains with three-dimensional (3D) network structures, which can absorb relatively large amounts of fluid. Because of the high water content, soft structure, and porosity of hydrogels, they closely resemble living tissues. Research in recent years shows that hydrogels have been applied in various fields, such as agriculture, biomaterials, the food industry, drug delivery, tissue engineering, and regenerative medicine. Along with the underlying technology improvements of hydrogel development, hydrogels can be expected to be applied in more fields. Although not all hydrogels have good biodegradability and biocompatibility, such as synthetic hydrogels (polyvinyl alcohol, polyacrylamide, polyethylene glycol hydrogels, etc.), their biodegradability and biocompatibility can be adjusted by modification of their functional group or incorporation of natural polymers. Hence, scientists are still interested in the biomedical applications of hydrogels due to their creative adjustability for different uses. In this review, we first introduce the basic information of hydrogels, such as structure, classification, and synthesis. Then, we further describe the recent applications of hydrogels in 3D cell cultures, drug delivery, wound dressing, and tissue engineering.
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Affiliation(s)
- Tzu-Chuan Ho
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (T.-C.H.); (C.-W.S.)
| | - Chin-Chuan Chang
- Department of Nuclear Medicine, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan;
- School of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Neuroscience Research Center, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Electrical Engineering, I-Shou University, Kaohsiung 840, Taiwan
| | - Hung-Pin Chan
- Department of Nuclear Medicine, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan;
| | - Tze-Wen Chung
- Biomedical Engineering Research and Development Center, National Yang Ming Chiao Tung University, Taipei 112, Taiwan;
| | - Chih-Wen Shu
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (T.-C.H.); (C.-W.S.)
| | - Kuo-Pin Chuang
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan;
| | - Tsai-Hui Duh
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 807, Taiwan;
- Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Ming-Hui Yang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan
- Center of General Education, Shu-Zen Junior College of Medicine and Management, Kaohsiung 821, Taiwan
| | - Yu-Chang Tyan
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan; (T.-C.H.); (C.-W.S.)
- Department of Nuclear Medicine, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan;
- School of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan;
- Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 807, Taiwan
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14
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Hacker L, Wabnitz H, Pifferi A, Pfefer TJ, Pogue BW, Bohndiek SE. Criteria for the design of tissue-mimicking phantoms for the standardization of biophotonic instrumentation. Nat Biomed Eng 2022; 6:541-558. [PMID: 35624150 DOI: 10.1038/s41551-022-00890-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 02/07/2022] [Indexed: 01/08/2023]
Abstract
A lack of accepted standards and standardized phantoms suitable for the technical validation of biophotonic instrumentation hinders the reliability and reproducibility of its experimental outputs. In this Perspective, we discuss general criteria for the design of tissue-mimicking biophotonic phantoms, and use these criteria and state-of-the-art developments to critically review the literature on phantom materials and on the fabrication of phantoms. By focusing on representative examples of standardization in diffuse optical imaging and spectroscopy, fluorescence-guided surgery and photoacoustic imaging, we identify unmet needs in the development of phantoms and a set of criteria (leveraging characterization, collaboration, communication and commitment) for the standardization of biophotonic instrumentation.
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Affiliation(s)
- Lina Hacker
- Department of Physics, University of Cambridge, Cambridge, UK.,Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Heidrun Wabnitz
- Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany
| | | | | | - Brian W Pogue
- Thayer School of Engineering, Dartmouth, Hanover, NH, USA
| | - Sarah E Bohndiek
- Department of Physics, University of Cambridge, Cambridge, UK. .,Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK.
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15
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Hydrogels as Corneal Stroma Substitutes for In Vitro Evaluation of Drug Ocular Permeation. Pharmaceutics 2022; 14:pharmaceutics14040850. [PMID: 35456684 PMCID: PMC9027330 DOI: 10.3390/pharmaceutics14040850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/08/2022] [Accepted: 04/11/2022] [Indexed: 11/17/2022] Open
Abstract
Hydrogels are complex hydrophilic structures, consisting of crosslinked homopolymers or copolymers insoluble in water. Due to their controllable bio-physicochemical properties mimicking the morphology of the native extracellular matrix, they are a key part of a lot of research fields, including medicine, pharmaceutics, and tissue engineering. This paper was focused on the preparation and characterization of hydrogels from different blends of polyvinyl alcohol (PVA) with microcrystalline cellulose (MCC) and gelatin (GEL) at various ratios, and from gelatin and chitosan alone to understand their feasibility of utilizing as corneal stroma substitutes in permeability tests for drug candidate molecules in early stages of their development. The characterization was carried out by differential scanning calorimetry, electron microscopy (SEM), water content, mass loss, water permeability, wettability, and tensile stress–strain tests. After the physicochemical characterization, PVA/MCC blend and chitosan proved to be the most promising constructs, showing negligible mass loss after immersion in aqueous medium for two weeks and low hydrodynamic permeability. They were then employed in drug molecules permeation studies and these data were compared to that obtained through excised tissues. The results obtained showed that PVA/MCC hydrogels have similar mechanical and permeability properties to corneal stroma.
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16
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Cheng J, Liu Q, Zhang Y, Wang Z, Gao M, Li S. Preparation and properties of antibacterial and antioxidant mango peel extract/polyvinyl alcohol composite films. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.16206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Jun Cheng
- College of Food and Biological Engineering Jimei University Xiamen China
| | - Qun Liu
- College of Food and Biological Engineering Jimei University Xiamen China
| | - Yucang Zhang
- College of Food and Biological Engineering Jimei University Xiamen China
| | - Zhifen Wang
- School of Chemical Engineering and Technology Hainan University Haikou China
| | - Mengmeng Gao
- School of Chemical Engineering and Technology Hainan University Haikou China
| | - Siyuan Li
- School of Chemical Engineering and Technology Hainan University Haikou China
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17
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Podorozhko EA, Buzin MI, Golubev EK, Shcherbina MA, Lozinsky VI. A Study of Cryostructuring of Polymer Systems. 59. Effect of Cryogenic Treatment of Preliminarily Deformed Poly(vinyl alcohol) Cryogels on Their Physicochemical Properties. COLLOID JOURNAL 2021. [DOI: 10.1134/s1061933x21050112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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18
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Crolla JP, Britton MM, Espino DM, Thomas-Seale LEJ. The dynamic viscoelastic characterisation and magnetic resonance imaging of poly(vinyl alcohol) cryogel: Identifying new attributes and opportunities. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2021; 129:112383. [PMID: 34579902 DOI: 10.1016/j.msec.2021.112383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/28/2021] [Accepted: 08/15/2021] [Indexed: 10/20/2022]
Abstract
Poly(vinyl alcohol) (PVA) cryogel is a biocompatible, synthetic hydrogel, compatible with magnetic resonance (MR) imaging. It is widely used as a biomaterial in tissue scaffolds and mimics to test various diagnostic techniques. The aim of this study is to characterise the effect of varying PVA concentration, molecular weight (MW) and manufacturing protocol on the viscoelastic mechanical properties and MR T2 relaxation time. Further to this MR imaging (MRI) was investigated as a method to quantify material homogeneity. Cylindrical samples of PVA, of varying MW, concentration and number of freeze thaw cycles (FTCs), were manufactured. Dynamic mechanical analysis was performed to evaluate the storage and loss moduli between frequencies of 0.5 and 10 Hz. MR T2 relaxation maps were imaged using a 7 T MRI instrument. Storage and loss moduli were shown to increase with MW, concentration, or the number of FTCs; with storage modulus ranging from 55 kPa to 912 kPa and loss modulus ranging from 6 kPa to 103 kPa. MR T2 relaxation time was shown to increase linearly with PVA concentration. The qualitative and quantitative heterogeneity of the PVA sample were identified through MR T2 relaxation time maps. Excitingly, PVA demonstrated a composition-dependent casual correlation between the viscoelastic mechanical properties and MR T2 relaxation time. In conclusion, this research thoroughly characterised the viscoelastic mechanical properties of PVA to support its extensive use as a biomaterial, and demonstrated the use of MRI to non-invasively identify sample heterogeneity and to predict the composition-dependent viscoelastic properties of PVA.
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Affiliation(s)
- J P Crolla
- Dept. of Mechanical Engineering, University of Birmingham, Birmingham B15 2TT, UK.
| | - M M Britton
- School of Chemistry, University of Birmingham, Birmingham B15 2TT, UK
| | - D M Espino
- Dept. of Mechanical Engineering, University of Birmingham, Birmingham B15 2TT, UK
| | - L E J Thomas-Seale
- Dept. of Mechanical Engineering, University of Birmingham, Birmingham B15 2TT, UK
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19
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Crolla JP, Britton MM, Espino DM, Thomas-Seale LEJ. The orthotropic viscoelastic characterisation of sub-zero 3D-printed poly(vinyl alcohol) cryogel. MRS ADVANCES 2021; 6:467-471. [PMID: 34721891 PMCID: PMC8550303 DOI: 10.1557/s43580-021-00086-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/11/2021] [Indexed: 11/13/2022]
Abstract
Abstract
Poly(vinyl alcohol) cryogel (PVA) is a versatile biomaterial used to replicate the biomechanics of tissues. Additive manufacture (AM) at sub-zero (°C) temperatures enables the manufacture of PVA with complex geometry; however, the effect of processing parameters on the mechanical properties of PVA has not been evaluated. The aim of this study is to understand the impact of print nozzle diameter and orientation on the viscoelastic mechanical properties of PVA. Samples of sub-zero AM PVA, with different filament thicknesses, were tested under tension relative to the print direction, to calculate the storage and loss moduli. As the nozzle size was decreased, AM PVA exhibited more pronounced orthotropic properties; the smallest size showed a 33% decrease in storage moduli when tested perpendicular to the print direction, as opposed to parallel. This study has demonstrated the ability of sub-zero AM to tailor the orthotropic properties of PVA.
Graphic abstract
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Affiliation(s)
- J. P. Crolla
- Dept. of Mechanical Engineering, University of Birmingham, Birmingham, B15 2TT UK
| | - M. M. Britton
- School of Chemistry, University of Birmingham, Birmingham, B15 2TT UK
| | - D. M. Espino
- Dept. of Mechanical Engineering, University of Birmingham, Birmingham, B15 2TT UK
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20
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Bui HT, Khair N, Yeats B, Gooden S, James SP, Dasi LP. Transcatheter Heart Valves: A Biomaterials Perspective. Adv Healthc Mater 2021; 10:e2100115. [PMID: 34038627 DOI: 10.1002/adhm.202100115] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/23/2021] [Indexed: 11/11/2022]
Abstract
Heart valve disease is prevalent throughout the world, and the number of heart valve replacements is expected to increase rapidly in the coming years. Transcatheter heart valve replacement (THVR) provides a safe and minimally invasive means for heart valve replacement in high-risk patients. The latest clinical data demonstrates that THVR is a practical solution for low-risk patients. Despite these promising results, there is no long-term (>20 years) durability data on transcatheter heart valves (THVs), raising concerns about material degeneration and long-term performance. This review presents a detailed account of the materials development for THVRs. It provides a brief overview of THVR, the native valve properties, the criteria for an ideal THV, and how these devices are tested. A comprehensive review of materials and their applications in THVR, including how these materials are fabricated, prepared, and assembled into THVs is presented, followed by a discussion of current and future THVR biomaterial trends. The field of THVR is proliferating, and this review serves as a guide for understanding the development of THVs from a materials science and engineering perspective.
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Affiliation(s)
- Hieu T. Bui
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Nipa Khair
- School of Advanced Materials Discovery Colorado State University 700 Meridian Ave Fort Collins CO 80523 USA
| | - Breandan Yeats
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Shelley Gooden
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Susan P. James
- School of Advanced Materials Discovery Colorado State University 700 Meridian Ave Fort Collins CO 80523 USA
| | - Lakshmi Prasad Dasi
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
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21
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Alakhtar A, Emmott A, Hart C, Mongrain R, Leask RL, Lachapelle K. 3D printed ascending aortic simulators with physiological fidelity for surgical simulation. BMJ SIMULATION & TECHNOLOGY ENHANCED LEARNING 2021; 7:536-542. [DOI: 10.1136/bmjstel-2021-000868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/28/2021] [Indexed: 11/04/2022]
Abstract
IntroductionThree-dimensional (3D) printed multimaterial ascending aortic simulators were created to evaluate the ability of polyjet technology to replicate the distensibility of human aortic tissue when perfused at physiological pressures.MethodsSimulators were developed by computer-aided design and 3D printed with a Connex3 Objet500 printer. Two geometries were compared (straight tube and idealised aortic aneurysm) with two different material variants (TangoPlus pure elastic and TangoPlus with VeroWhite embedded fibres). Under physiological pressure, β Stiffness Index was calculated comparing stiffness between our simulators and human ascending aortas. The simulators’ material properties were verified by tensile testing to measure the stiffness and energy loss of the printed geometries and composition.ResultsThe simulators’ geometry had no effect on measured β Stiffness Index (p>0.05); however, β Stiffness Index increased significantly in both geometries with the addition of embedded fibres (p<0.001). The simulators with rigid embedded fibres were significantly stiffer than average patient values (41.8±17.0, p<0.001); however, exhibited values that overlapped with the top quartile range of human tissue data suggesting embedding fibres can help replicate pathological human aortic tissue. Biaxial tensile testing showed that fiber-embedded models had significantly higher stiffness and energy loss as compared with models with only elastic material for both tubular and aneurysmal geometries (stiffness: p<0.001; energy loss: p<0.001). The geometry of the aortic simulator did not statistically affect the tensile tested stiffness or energy loss (stiffness: p=0.221; energy loss: p=0.713).ConclusionWe developed dynamic ultrasound-compatible aortic simulators capable of reproducing distensibility of real aortas under physiological pressures. Using 3D printed composites, we are able to tune the stiffness of our simulators which allows us to better represent the stiffness variation seen in human tissue. These models are a step towards achieving better simulator fidelity and have the potential to be effective tools for surgical training.
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22
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Tibamoso-Pedraza G, Navarro I, Dion P, Raboisson MJ, Lapierre C, Miró J, Ratté S, Duong L. Design of heart phantoms for ultrasound imaging of ventricular septal defects. Int J Comput Assist Radiol Surg 2021; 17:177-184. [PMID: 34021458 DOI: 10.1007/s11548-021-02406-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/11/2021] [Indexed: 12/24/2022]
Abstract
PURPOSE Ventricular septal defects (VSDs) are common congenital heart malformations. Echocardiography used during VSD hybrid cardiac procedures requires extensive training for image acquisition and interpretation. Cardiac surgery simulators with heart phantoms have shown usefulness for such training, but they are limited in visualization and characterization of complex VSD. This study explores a new method to build patient-specific heart phantoms with VSD, with proper tissue echogenicity for ultrasound imaging. METHODS Heart phantoms were designed from preoperative imaging of three patients with complex VSDs. Each whole heart phantom, including atrial and ventricular septums, was obtained by manual segmentation and by surface reconstruction, then by molding and by casting in different materials. Heart phantoms in silicone and polyvinyl alcohol cryogel (PVA-C) were considered, and they were reconstructed in 3-D using 2-D freehand ultrasound imaging. RESULTS An electromagnetic measurement system was used to measure the mean VSD diameters from the heart phantoms. Errors were evaluated below 1.0 mm for mean VSD diameters between 6.2 and 7.5 mm. CONCLUSION Patient-specific heart phantoms promise for representing complex heart malformations such as VSDs. PVA-C showed better tissue echogenicity than silicone for VSDs visualization and characterization.
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Affiliation(s)
- Gerardo Tibamoso-Pedraza
- Interventional Imaging Lab, Department of Software and IT Engineering, École de technologie supérieure, 1100 Notre-Dame West, Montreal, H3C 1K3, Canada.
| | - Iñaki Navarro
- Cardiology, Department of Pediatrics, CHU Sainte-Justine, Montreal, H3T 1C5, Canada
| | - Patrice Dion
- Interventional Imaging Lab, Department of Software and IT Engineering, École de technologie supérieure, 1100 Notre-Dame West, Montreal, H3C 1K3, Canada
| | | | - Chantale Lapierre
- Cardiology, Department of Pediatrics, CHU Sainte-Justine, Montreal, H3T 1C5, Canada
| | - Joaquim Miró
- Cardiology, Department of Pediatrics, CHU Sainte-Justine, Montreal, H3T 1C5, Canada
| | - Sylvie Ratté
- Interventional Imaging Lab, Department of Software and IT Engineering, École de technologie supérieure, 1100 Notre-Dame West, Montreal, H3C 1K3, Canada
| | - Luc Duong
- Interventional Imaging Lab, Department of Software and IT Engineering, École de technologie supérieure, 1100 Notre-Dame West, Montreal, H3C 1K3, Canada
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Remiš T, Bělský P, Kovářík T, Kadlec J, Ghafouri Azar M, Medlín R, Vavruňková V, Deshmukh K, Sadasivuni KK. Study on Structure, Thermal Behavior and Viscoelastic Properties of Nanodiamond-Reinforced Poly (vinyl alcohol) Nanocomposites. Polymers (Basel) 2021; 13:1426. [PMID: 33925200 PMCID: PMC8124898 DOI: 10.3390/polym13091426] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 12/15/2022] Open
Abstract
In this work, advanced polymer nanocomposites comprising of polyvinyl alcohol (PVA) and nanodiamonds (NDs) were developed using a single-step solution-casting method. The properties of the prepared PVA/NDs nanocomposites were investigated using Raman spectroscopy, small- and wide-angle X-ray scattering (SAXS/WAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). It was revealed that the tensile strength improved dramatically with increasing ND content in the PVA matrix, suggesting a strong interaction between the NDs and the PVA. SEM, TEM, and SAXS showed that NDs were present in the form of agglomerates with an average size of ~60 nm with primary particles of diameter ~5 nm. These results showed that NDs could act as a good nanofiller for PVA in terms of improving its stability and mechanical properties.
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Affiliation(s)
- Tomáš Remiš
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Petr Bělský
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Tomáš Kovářík
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Jaroslav Kadlec
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Mina Ghafouri Azar
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Rostislav Medlín
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Veronika Vavruňková
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
| | - Kalim Deshmukh
- New Technologies—Research Centre, University of West Bohemia, Univerzitní 8, 306 14 Plzeň, Czech Republic; (P.B.); (T.K.); (J.K.); (M.G.A.); (R.M.); (V.V.); (K.D.)
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Mostakhdemin M, Nand A, Ramezani M. A novel assessment of microstructural and mechanical behaviour of bilayer silica-reinforced nanocomposite hydrogels as a candidate for artificial cartilage. J Mech Behav Biomed Mater 2021; 116:104333. [PMID: 33494020 DOI: 10.1016/j.jmbbm.2021.104333] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 12/23/2020] [Accepted: 01/12/2021] [Indexed: 12/20/2022]
Abstract
The complex structure of healthy articular cartilage facilitates the joint withstanding the imposed pressures and retaining interstitial fluid to lessen stresses on its soft tissue, while easing the locomotion and minimising friction between cartilage mates. Avascular nature of this tissue results in unrecoverable damaged lesions and severe pain over time. Polymeric hydrogels are promising candidate materials for the replacement of the damaged cartilage. Hence, a tough bilayer nanocomposite acrylamide-acrylic acid hydrogel reinforced with silica nanoparticles (SNPs) was designed and synthesised. The mechanical characterisations showed a significant increase in compressive strength up to 1.4 MPa and doubled elastic modulus (240 kPa) by utilising only 0.6 wt% SNPs compared to the non-reinforced hydrogel. The optimum amounts of monomers and SNPs resulted in the compression of samples up to 85% strain without failure. Viscoelastic responses improved as the stress relaxation lessened to half in all nanocomposite hydrogels. Diffusion rate theory was applied, and the results showed to what extent elastic modulus results in an improvement in stress relaxation. The proposed hydrogel formulation exhibited the poroelastic relaxation occurred before viscoelastic relaxation at the time elapses under stress relaxation tests. SEM images showed uniform funnel-like porosity with 570 μm thick lubricious layer, which is an important feature to retain interstitial fluid. Energy-dispersive X-ray spectroscopy was conducted to characterise the elemental composition within the polymeric macrostructure.
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Affiliation(s)
- Mohammad Mostakhdemin
- Department of Mechanical Engineering, Auckland University of Technology, Auckland, New Zealand.
| | - Ashveen Nand
- School of Environmental and Animal Sciences and School of Healthcare and Social Practice, Unitec Institute of Technology, Auckland, New Zealand
| | - Maziar Ramezani
- Department of Mechanical Engineering, Auckland University of Technology, Auckland, New Zealand.
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Taghizadeh B, Ghavami L, Derakhshankhah H, Zangene E, Razmi M, Jaymand M, Zarrintaj P, Zarghami N, Jaafari MR, Moallem Shahri M, Moghaddasian A, Tayebi L, Izadi Z. Biomaterials in Valvular Heart Diseases. Front Bioeng Biotechnol 2020; 8:529244. [PMID: 33425862 PMCID: PMC7793990 DOI: 10.3389/fbioe.2020.529244] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 11/16/2020] [Indexed: 01/07/2023] Open
Abstract
Valvular heart disease (VHD) occurs as the result of valvular malfunction, which can greatly reduce patient's quality of life and if left untreated may lead to death. Different treatment regiments are available for management of this defect, which can be helpful in reducing the symptoms. The global commitment to reduce VHD-related mortality rates has enhanced the need for new therapeutic approaches. During the past decade, development of innovative pharmacological and surgical approaches have dramatically improved the quality of life for VHD patients, yet the search for low cost, more effective, and less invasive approaches is ongoing. The gold standard approach for VHD management is to replace or repair the injured valvular tissue with natural or synthetic biomaterials. Application of these biomaterials for cardiac valve regeneration and repair holds a great promise for treatment of this type of heart disease. The focus of the present review is the current use of different types of biomaterials in treatment of valvular heart diseases.
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Affiliation(s)
- Bita Taghizadeh
- Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Laleh Ghavami
- Laboratory of Biophysics and Molecular Biology, Department of Biophysics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Hossein Derakhshankhah
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Ehsan Zangene
- Department of Bioinformatics, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Mahdieh Razmi
- Department of Biochemistry, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Mehdi Jaymand
- Nano Drug Delivery Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Payam Zarrintaj
- Polymer Engineering Department, Faculty of Engineering, Urmia University, Urmia, Iran
| | - Nosratollah Zarghami
- Department of Medical Biotechnology, School of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahmoud Reza Jaafari
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Pharmaceutical Nanotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Matin Moallem Shahri
- Cardiology Department, Taleghani Trauma Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI, United States
| | - Zhila Izadi
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
- Department of Regenerative Medicine, Cell Science Research Center, Academic Center for Education, Culture and Research (ACECR), Royan Institute for Stem Cell Biology and Technology, Tehran, Iran
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26
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Villa E, Arteaga-Marrero N, González-Fernández J, Ruiz-Alzola J. Bimodal microwave and ultrasound phantoms for non-invasive clinical imaging. Sci Rep 2020; 10:20401. [PMID: 33230246 PMCID: PMC7684317 DOI: 10.1038/s41598-020-77368-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 11/05/2020] [Indexed: 11/25/2022] Open
Abstract
A precise and thorough methodology is presented for the design and fabrication of bimodal phantoms to be used in medical microwave and ultrasound applications. Dielectric and acoustic properties of human soft tissues were simultaneously mimicked. The phantoms were fabricated using polyvinyl alcohol cryogel (PVA-C) as gelling agent at a 10% concentration. Sucrose was employed to control the dielectric properties in the microwave spectrum, whereas cellulose was used as acoustic scatterer for ultrasound. For the dielectric properties at microwaves, a mathematical model was extracted to calculate the complex permittivity of the desired mimicked tissues in the frequency range from 500 MHz to 20 GHz. This model, dependent on frequency and sucrose concentration, was in good agreement with the reference Cole-Cole model. Regarding the acoustic properties, the speed of sound and attenuation coefficient were employed for validation. In both cases, the experimental data were consistent with the corresponding theoretical values for soft tissues. The characterization of these PVA-C phantoms demonstrated a significant performance for simultaneous microwave and ultrasound operation. In conclusion, PVA-C has been validated as gelling agent for the fabrication of complex multimodal phantoms that mimic soft tissues providing a unique tool to be used in a range of clinical applications.
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Affiliation(s)
- Enrique Villa
- IACTEC Medical Technology Group, Instituto de Astrofísica de Canarias, San Cristóbal de La Laguna, 38205, Spain.
| | - Natalia Arteaga-Marrero
- IACTEC Medical Technology Group, Instituto de Astrofísica de Canarias, San Cristóbal de La Laguna, 38205, Spain
| | - Javier González-Fernández
- Department of Biomedical Engineering, Instituto Tecnológico de Canarias, Santa Cruz de Tenerife, 38009, Spain
| | - Juan Ruiz-Alzola
- IACTEC Medical Technology Group, Instituto de Astrofísica de Canarias, San Cristóbal de La Laguna, 38205, Spain
- Department of Signals and Communications, University Research Institute for Biomedical and Health Research, Universidad de Las Palmas de Gran Canaria, Las Palmas de Gran Canaria, 35016, Spain
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Dadgar N, Ghiaseddin A, Irani S, Rabbani S, Tafti SHA, Soufizomorrod M, Soleimani M. Cartilage tissue engineering using injectable functionalized Demineralized Bone Matrix scaffold with glucosamine in PVA carrier, cultured in microbioreactor prior to study in rabbit model. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 120:111677. [PMID: 33545839 DOI: 10.1016/j.msec.2020.111677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/22/2020] [Accepted: 10/22/2020] [Indexed: 01/08/2023]
Abstract
Using 3D model of injectable scaffolds for cartilage tissue engineering is one of the challenges that should be addressed to avoid invasive surgery for treatment. For this purpose, chondrocytes on Demineralized Bone Matrix (DBM) scaffolds functionalized with glucosamine in 20% polyvinyl alcohol (PVA) as a carrier was applied to the micro-bioreactor in-vitro, then the study was continued on in-vivo stage. Scaffold biocompatibility tests were performed and the mechanical and physicochemical properties were studied showing the fact that DBM was functionalized by Glucosamine, scaffold degradation rate was 53% after 720 h and swelling ratio was 2.5 times after 16 h, injectable scaffold demonstrated better mechanical characteristics (P < 0.05) than other concentrations of PVA. Consequently, in-vitro tests, including live-dead imaging resulting in 99% viability after 14 days (P < 0.001), DAPI staining and scanning electron microscope imaging were performed to determine the number and viability of the cells on the scaffold, showing a cells proliferation property of this group compared with the control after 14 days (P < 0.0001), then relative gene expression was evaluated and protein expression was assessed. The overall chondrogenic gene expression improved (P < 0.05) compared to the control (2D culture). Subsequently, the scaffold were loaded with chondrocytes and injected into the cartilage lesion part After 24 weeks of surgery, MRI and immunocytochemistry were performed. Then all outputs proved that the scaffold plus cell group had a significantly higher topological score (P < 0.0001) than other groups compared to normal cartilage. Finally, studies have shown that transplantation of chondrocytes in DBM, polyvinyl alcohol and glucosamine scaffold through one surgical stage improves cartilage lesion and it can be considered as a breakthrough in tissue engineering.
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Affiliation(s)
- Neda Dadgar
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Ali Ghiaseddin
- Biomedical Engineering Division, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran; Department of Anatomical Sciences, Faculty of Medical Science, Tarbiat Modares University, Tehran, Iran; Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Shiva Irani
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Shahram Rabbani
- Research Center for Advanced Technologies in Cardiovascular Medicine, Cardiovascular diseases Research institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Hossein Ahmadi Tafti
- Research Center for Advanced Technologies in Cardiovascular Medicine, Cardiovascular diseases Research institute, Tehran University of Medical Sciences, Tehran, Iran
| | - Mina Soufizomorrod
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Masoud Soleimani
- Department of Hematology and Cell Therapy, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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28
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Jin L, He H, Yang F, Xu L, Guo G, Wang Y. Tough pNAGA hydrogel hybridized porcine pericardium for the pre-mounted TAVI valve with improved anti-tearing properties and hemocompatibility. ACTA ACUST UNITED AC 2020; 15:065013. [PMID: 32615546 DOI: 10.1088/1748-605x/aba239] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The rate of adoption of transcatheter aortic valve implantation (TAVI) is increasing rapidly, due to the procedure being less invasive. However, TAVI still faces problems relating to durability, the potential incidence of thrombosis, and the inconvenience of storage in glutaraldehyde (Glut) solution. In this work, a tough hydrogel poly(N-acryloyl glycinamide) (pNAGA) is hybridized with Glut-crosslinked porcine pericardium (Glut-PP) via in situ polymerization and glycerolization, so as to obtain dry leafet material for the fabrication of a pre-mounted bioprosthetic heart valve (BHV). The tensile strength, anti-shearing, and anti-tearing properties of the valve are significantly improved by the process of hydrogel hybridization. Following a period of dry-state compression as a simulation for the crimping process of pre-mounted TAV, pNAGA/Glut-PP showed full recovery without structural damage when fully rehydrated. The introduction of pNAGA also improved the blood compatibility of the tissue, with less clot formation and fewer blood cells adhering to the surface of pNAGA/Glut-PP than is found with Glut-PP. Subcutaneous implantation in rats showed that pNAGA/Glut-PP induced a decreased inflammatory response compared with Glut-PP. These results indicate that the strategy for hybridization with hydrogel could be a potential method for preparing pre-mounted TAVs with an improved performance.
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Xiong X, Sun J, Hu D, Xiao C, Wang J, Zhuo Q, Qin C, Dai L. Fabrication of polyvinyl alcohol hydrogels with excellent shape memory and ultraviolet-shielding behavior via the introduction of tea polyphenols. RSC Adv 2020; 10:35226-35234. [PMID: 35515656 PMCID: PMC9056856 DOI: 10.1039/d0ra06053d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 09/01/2020] [Indexed: 11/21/2022] Open
Abstract
Shape-memory hydrogels are expected to be used not only in an ordinary environment, but also in some special environments, such as under ultraviolet (UV) irradiation. Developing novel shape-memory polyvinyl alcohol (PVA)/tea polyphenol (TP) hydrogels with UV shielding performance is realistically important in application fields. Herein, we designed functional PVA/TP hydrogels with excellent UV-shielding ability and improved the shape memory on hot water stimuli. This study shows that the abundant hydrogen bonds between PVA and TP are the source of shape memory. The PVA hydrogels with 8 wt% TP loading could approximately recover their original shape after deformation when immersed in water at 50 °C for 30 s. Meanwhile, the hydrogels also had excellent UV shielding capacity. After ageing under UV for 16 days, the observed shape of the hydrogel with 8 wt% TP loading retained 74.7% of the original, and the hydrogel could effectively protect the skin of mice from damage under 10 mW cm-2 UV irradiation. With the understanding of the UV-shielding behavior of hydrogels, this study has been able to generate biomedical materials for human skin protection, specifically skin covering the joint areas, where shape memory of the applied materials is essential.
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Affiliation(s)
- Xike Xiong
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Jun Sun
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Di Hu
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Chao Xiao
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Jianjun Wang
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Qiqi Zhuo
- College of Material Science & Engineering, Jiangsu University of Science and Technology Zhenjiang Jiangsu 212003 People's Republic of China
| | - Chuanxiang Qin
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
| | - Lixing Dai
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University Suzhou Jiangsu 215123 People's Republic of China
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30
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Galvis-García ES, Sobrino-Cossío S, Reding-Bernal A, Contreras-Marín Y, Solórzano-Acevedo K, González-Zavala P, Quispe-Siccha RM. Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasound-elastography. World J Gastroenterol 2020; 26:5169-5180. [PMID: 32982117 PMCID: PMC7495029 DOI: 10.3748/wjg.v26.i34.5169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/27/2020] [Accepted: 08/14/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Endoscopic ultrasound (EUS) and endoscopic ultrasound elastography (EUS-E) simulation lessens the learning curve; however, models lack realism, diminishing competitiveness.
AIM To standardize the mechanical properties of polyvinyl alcohol (PVA) hydrogel for simulating organs and digestive lesions.
METHODS PVA hydrogel (Sigma Aldrich, degree of hydrolysis 99%) for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México “Dr. Eduardo Liceaga”, Mexico City. We evaluated physical, contrast, elasticity and deformation coefficient characteristics in lesions, applying Kappa’s concordance and satisfaction questionnaire (Likert 4-points).
RESULTS PVA hydrogel showed stable mechanical properties. Density depended on molecular weight (MW) and concentration (C). PVA bblocks with the greatest density showed lowest tensile strength (r = -0.8, P = 0.01). Lesions were EUS-graphically visible. Homogeneous and heterogeneous examples were created from PVA blocks or PVA phantoms, exceeding (MW2 = 146000-186000, C9 = 15% and C10 = 20%) with a density under (MW1 = 85000-124000, C1 = 7% and C2 = 9%). We calculated elasticity and deformation parameters of solid (blue) areas, contrasting with the norm (Kappa = 0.8; high degree of satisfaction).
CONCLUSION PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E, facilitating practice and reducing risk. Repetition amplified skills, while reducing the learning curve.
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Affiliation(s)
- Elymir S Galvis-García
- Unidad de Endoscopía Gastrointestinal, Hospital General de México "Dr. Eduardo Liceaga", Mexico 06720, Mexico
| | - Sergio Sobrino-Cossío
- Unidad de Endoscopia y Fisiología Digestiva, Hospital Ángeles del Pedregal, Mexico 10700, Mexico
| | - Arturo Reding-Bernal
- Dirección de Investigación, Hospital General de México “Dr. Eduardo Liceaga”, Mexico 06720, Mexico
| | - Yesica Contreras-Marín
- Unidad Profesional Interdisciplinaria de Biotecnología and Unidad de Investigación y Desarrollo Tecnológico, Instituto Politécnico Nacional and Hospital General de México "Dr. Eduardo Liceaga", Mexico 06720, Mexico
| | - Karina Solórzano-Acevedo
- Unidad Profesional Interdisciplinaria de Biotecnología and Unidad de Investigación y Desarrollo Tecnológico, Instituto Politécnico Nacional and Hospital General de México "Dr. Eduardo Liceaga", Mexico 06720, Mexico
| | - Patricia González-Zavala
- Instituto de Investigaciones en Materiales and Unidad de Investigación y Desarrollo Tecnológico, Universidad Nacional Autónoma de México and Hospital General de México "Dr. Eduardo Liceaga", Mexico 06720, Mexico
| | - Rosa M Quispe-Siccha
- Unidad de Investigación y Desarrollo Tecnológico, Hospital General de México "Dr. Eduardo Liceaga", Mexico 06720, Mexico
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Nafo W, Al-Mayah A. Mechanical characterization of PVA hydrogels' rate-dependent response using multi-axial loading. PLoS One 2020; 15:e0233021. [PMID: 32396571 PMCID: PMC7217472 DOI: 10.1371/journal.pone.0233021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/27/2020] [Indexed: 11/18/2022] Open
Abstract
The time-dependent properties of rubber-like synthesized and biological materials are crucial for their applications. Currently, this behavior is mainly measured using axial tensile test, compression test, or indentation. Limited studies performed on using multi-axial loading measurements of time-dependent material behavior exist in the literature. Therefore, the aim of this study is to investigate the viscoelastic response of rubber-like materials under multi-axial loading using cavity expansion and relaxation tests. The tests were performed on PVA hydrogel specimens. Three hyperelasitc models and one term Prony series were used to characterize the viscoelastic response of the hydrogels. Finite element (FE) simulations were performed to verify the validity of the calibrated material coefficients by reproducing the experimental results. The excellent agreement between the experimental, analytical and numerical data proves the capability of the cavity expansion technique to measure the time-dependent behavior of viscoelastic materials.
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Affiliation(s)
- Wanis Nafo
- Civil and Environmental Engineering Department, University of Waterloo, Waterloo, Ontario, Canada
| | - Adil Al-Mayah
- Civil and Environmental Engineering Department, University of Waterloo, Waterloo, Ontario, Canada
- Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario, Canada
- Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, Ontario, Canada
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Azar T, McLennan S, Walsh M, Angeles J, Kövecses J, Jaramillo T, Mongrain R, Cecere R. Dynamic Left Atrioventricular Phantom Test Bed Emulating Mitral Valve Motion. J Med Device 2020. [DOI: 10.1115/1.4046862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Abstract
Novel catheter-based medical procedures targeting heart valve structures are currently under development. These techniques entail installing a prosthetic implant on valves inside a beating heart. The development of these approaches requires a simple and effective validation test bed. Current early process testing methods rely on both static and dynamically pressurized excised porcine hearts. The variability between excised-tissue mechanical properties poses problems of reproducibility. In addition, these test beds do not emulate annulus motion, which affects the implant installation. A reproducible phantom of the left atrioventricular chambers was developed. The system consists of a hydraulic constant flow arrangement and a polyvinyl alcohol phantom heart with material properties that mimic passive myocardium mechanical properties and annulus motion. The system was then used to emulate blood flow through an actual heart. The building process starts by obtaining an accurate computer-aided design (CAD) model of a human heart, from which, a mold is produced using a novel rapid-freezing prototyping method and computer numerical control machining. The phantom is then cast-out of polyvinyl alcohol (PVA), a hydrogel, whose mechanical properties are set by subjecting the phantom to freeze and thaw cycles. Subsequently, blood flow is emulated at a constant volumetric rate at the atrial pressure observed in a healthy adult human heart at rest. The annulus motion is implemented by suturing the outside of the phantom to a one-degree-of-freedom cam-follower mechanism reproducing valve motion. Such test beds could play a significant role in future development of medical devices.
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Affiliation(s)
- Toufic Azar
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Stewart McLennan
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Michael Walsh
- Department of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick, Limerick V94T9PX, Ireland
| | - Jorge Angeles
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Jozsef Kövecses
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Tabitha Jaramillo
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Rosaire Mongrain
- Department of Mechanical Engineering, McGill University, Montreal, QC H3A 0C3, Canada
| | - Renzo Cecere
- McGill University Health Centre, McGill University, Royal Victoria Hospital, Montreal, QC H3A 2A7, Canada
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Investigation of Gel Properties of Novel Cryo-Clay-Silica Polymer Networks. Gels 2020; 6:gels6020011. [PMID: 32235606 PMCID: PMC7345029 DOI: 10.3390/gels6020011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/10/2020] [Accepted: 03/27/2020] [Indexed: 11/21/2022] Open
Abstract
Several methods to increase the mechanical and swelling properties of Poly(N-isopropylacrylamide) gels are known. In this study different methods were combined to systematically alter the gel properties. The combination of nanocomposite and cryo gels as well as silica post modification was used to modulate the gel strength. This new cryo-clay-silica gel based on N-isopropylacrylamide was investigated in respect to degree of swelling, kinetic of thermo responsive behavior and tensile strength. Here, the properties of new cryo-clay-silica gel were compared with properties of clay-, silica-clay and cryo-clay gels.
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34
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He Z, Mongrain R, Lessard S, Chayer B, Cloutier G, Soulez G. Anthropomorphic and biomechanical mockup for abdominal aortic aneurysm. Med Eng Phys 2020; 77:60-68. [PMID: 31954613 DOI: 10.1016/j.medengphy.2019.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/08/2019] [Accepted: 12/15/2019] [Indexed: 11/16/2022]
Abstract
Abdominal aortic aneurysm (AAA) is an asymptomatic condition due to the dilation of abdominal aorta along with progressive wall degeneration, where rupture of AAA is life-threatening. Failures of AAA endovascular repair (EVAR) reflect our inadequate knowledge about the complex interaction between the aortic wall and medical devices. In this regard, we are presenting a hydrogel-based anthropomorphic mockup (AMM) to better understand the biomechanical constraints during EVAR. By adjusting the cryogenic treatments, we tailored the hydrogel to mimic the mechanical behavior of human AAA wall, thrombus and abdominal fat. A specific molding sequence and a pressurizing system were designed to reproduce the geometrical and diseased characteristics of AAA. A mechanically, anatomically and pathologically realistic AMM for AAA was developed for the first time, EVAR experiments were then performed with and without the surrounding fat. Substantial displacements of the aortic centerlines and vessel expansion were observed in the case without surrounding fat, revealing an essential framework created by the surrounding fat to account for the interactions with medical devices. In conclusion, the importance to consider surrounding tissue for the global deformation of AAA during EVAR was highlighted. Furthermore, potential use of this AMM for medical training was also suggested.
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Affiliation(s)
- Zinan He
- McGill University, 845 Sherbrooke Street West, Montréal, Québec H3A 0G4, Canada; Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint-Denis, Montréal, Québec H2X 0A9, Canada
| | - Rosaire Mongrain
- McGill University, 845 Sherbrooke Street West, Montréal, Québec H3A 0G4, Canada
| | - Simon Lessard
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint-Denis, Montréal, Québec H2X 0A9, Canada
| | - Boris Chayer
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint-Denis, Montréal, Québec H2X 0A9, Canada
| | - Guy Cloutier
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint-Denis, Montréal, Québec H2X 0A9, Canada; Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, Québec H3T 1J4, Canada
| | - Gilles Soulez
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), 900 Rue Saint-Denis, Montréal, Québec H2X 0A9, Canada; Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montréal, Québec H3T 1J4, Canada.
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35
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Mannarino MM, Bassett M, Donahue DT, Biggins JF. Novel high-strength thromboresistant poly(vinyl alcohol)-based hydrogel for vascular access applications. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2020; 31:601-621. [PMID: 31900047 DOI: 10.1080/09205063.2019.1706148] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Adherence of proteins, cells, and microorganisms to the surface of biomaterials used for vascular access contribute to device failure by thrombosis, occlusions, and infections. Current technologies for inhibiting these complications are limited to coatings and additives that are limited in duration of efficacy and often induce adverse side effects. In this work, we developed a novel composite hydrogel structure comprising of a porous poly(vinyl alcohol) (PVA) that is impregnated with poly(acrylic acid) (PAA) and heat treated to create a physically cross-linked high-strength hydrogel material. The swelling and mechanical properties can be controlled by the temperature and duration of heat treatment to increase the cross-link density of the matrix. The heat treated composite PVA/PAA hydrogel exhibits both the mechanical strength and durability of thermoplastic polyurethanes (TPUs) and the inherently non-thrombogenic surface functionality of PVA-based hydrogels without the use of chemical cross-linking agents. The composite hydrogels were found to maintain their mechanical integrity and surface functionality after accelerated aging in a simulated-use in vitro model for 162.5 days real-time equivalent. Relative to commercial catheter materials, the composite PVA/PAA hydrogel exhibited up to an average of 97% reduction in platelet adhesion when exposed to an in vitro blood loop model and a lower rate of tip occlusion due to thrombosis. This high-strength thromboresistant hydrogel could have a major impact as a novel biomaterial for use in vascular access applications to improve patient health.
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Pullulan/Poly(Vinyl Alcohol) Composite Hydrogels for Adipose Tissue Engineering. MATERIALS 2019; 12:ma12193220. [PMID: 31581444 PMCID: PMC6804089 DOI: 10.3390/ma12193220] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 09/25/2019] [Accepted: 09/28/2019] [Indexed: 01/10/2023]
Abstract
Composite hydrogels based on pullulan (HP) and poly(vinyl alcohol) (PVA) were both prepared by simple chemical crosslinking with sodium trimethaphosphate (STMP) or by dual crosslinking (simultaneously chemical crosslinking with STMP and physical crosslinking by freeze-thaw technique). The resulting hydrogels and cryogels were designed for tissue engineering applications. PVA, with two different molecular weights (47,000 and 125,000 g/mol; PVA47 and PVA125, respectively), as well as different P/PVA weight ratios were tested. The physico-chemical characterization of the hydrogels was performed by FTIR spectroscopy and scanning electron microscopy (SEM). The swelling kinetics, dissolution behavior, and degradation profiles in simulated physiological conditions (phosphate buffer at pH 7.4) were investigated. Pullulan concentration and the crosslinking method had significant effects on the pore size, swelling ratio, and degradation profiles. Cryogels exhibit lower swelling capacities than the conventional hydrogels but have better stability against hydrolitic degradation. Biocompatibility of the hydrogels was also investigated by both MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and LDH (lactaten dehydrogenase) assay. The MTT and LDH assays proved that dual crosslinked HP/PVA125 (75:25, w/w) scaffolds are more biocompatible and promote to a greater extent the adhesion and proliferation of L929 murine fibroblast cells than chemically crosslinked HP/PVA47 (50/50, w/w) scaffolds. Moreover, the HP/PVA125 cryogel had the best ability for the adipogenic differentiation of cells. The overall results demonstrated that the HP/PVA composite hydrogels or cryogels are suitable biomaterials for tissue engineering applications.
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Chitosan-Graft-Poly(N-Isopropylacrylamide)/PVA Cryogels as Carriers for Mucosal Delivery of Voriconazole. Polymers (Basel) 2019; 11:polym11091432. [PMID: 31480489 PMCID: PMC6780328 DOI: 10.3390/polym11091432] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 08/28/2019] [Accepted: 08/30/2019] [Indexed: 12/15/2022] Open
Abstract
The objective of this study was to prepare and characterize physically crosslinked gel formulations of chitosan (CS)-graft-poly(N-isopropyl acrylamide) (PNIPAAm) and polyvinyl alcohol (PVA) for smart delivery of an antifungal drug, Voriconazole, for mucosal applications. For this purpose, cryogels of CS-g-PNIPAAm/PVA and CS/PVA were tested by means of texture profile analysis and rheology to determine optimal matrix properties for topical application. The ratio of 75/25 v/v % CS-g-PNIPAAm/PVA was selected to be used for formulation since it gave low compressibility and hardness (1.2 and 0.6 N) as well as high adhesion properties and non-Newtonian flow behavior. The cryogels and formulations were further characterized by means of FTIR spectroscopy, swelling behavior, texture analysis, scanning electron microscopy (SEM), thermal (differential scanning calorimetry (DSC) and TGA), and rheological behavior. The drug loading capacity and in vitro release profile of the drug, storage stability, and cytotoxicity tests were also performed for the gel formulation. The FTIR, DSC, and TGA results verified the successful formation of cryogels. Swelling studies revealed a pH-dependent swelling ability with a maximum swelling degree of 1200% in acid and 990% in phosphate buffer (pH = 7.4). Thermal studies showed that CS-g-PNIPAAm/PVA 75/25 had higher thermal stability proving the structural complexity of the polymer. The loading capacity of Voriconazole was found to be 70% (w/w). The in vitro release profiles of Voriconazole showed Fickian release behavior for CS-g-PNIPAAm/PVA 75/25 gel with an approximate delivery of 38% within 8 h, slower than matrices containing unmodified chitosan. The storage stability test exhibited that the gel formulation was still stable even after aging for two months. Moreover, the cell culture assays revealed a non-toxic character of the polymeric matrix. Overall results showed that the CS-g-PNIPAAm/PVA 75/25 hydrogel has the potential to be used as a smart polymeric vehicle for topical applications.
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Crawford SA, Doyle MG, Amon CH, Forbes TL. Impact of Insertion Technique and Iliac Artery Anatomy on Fenestrated Endovascular Aneurysm Repair. J Endovasc Ther 2019; 26:797-804. [DOI: 10.1177/1526602819872499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Purpose: To develop a mechanically realistic aortoiliac model to evaluate anatomic variables associated with stent-graft rotation and to assess common deployment techniques that may contribute to rotation. Materials and Methods: Idealized aortoiliac geometries were constructed either through direct 3-dimensional (3D) printing (rigid) or through casting with polyvinyl alcohol using 3D-printed molds (flexible). Flexible model bending rigidity was controlled by altering wall thickness. Three flexible patient-specific models were also created based on the preoperative computed tomography angiograms. Zenith infrarenal and fenestrated devices were used in this study. The models were pressurized to 100 mm Hg with normal saline. Deployments were performed under fluoroscopy at 37°C. Rotation was calculated by tracking the change in position of gold markers affixed to the devices. Results: In the rigid idealized models, stent-graft rotation increased with increasing torsion; torsion levels of 1.6, 2.6, and 3.6 mm−1 had mean rotations of 5.2°±0.03°, 11.2°±4.8°, and 27.6°±13.0°, respectively (p<0.001). In the flexible models, the highest rotation (58°±3.0°) was observed in models with high torsion and high rigidity (7.5 mm−1 net torsion and 254 N·m2 flexural rigidity). No rotation was observed in the absence of torsion. Applying torque to the device during insertion significantly increased stent-graft rotation by an average of 28° across all levels of torsion (p<0.01). Multiple device insertions prior to deployment did not change the observed device rotation. The patient-specific models accurately predicted the degree of rotation seen intraoperatively to within 5°. Conclusion: Insertion technique plays an important role in the degree of stent-graft rotation during deployment. Our model suggests that in vivo correction of device orientation can increase the observed rotation and supports the concept of fully removing the device, adjusting the orientation, and subsequently reinserting. Additionally, increasing iliac artery torsion in the presence of increased vessel rigidity results in stent-graft rotation.
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Affiliation(s)
- Sean A. Crawford
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Division of Vascular Surgery, University Health Network, Peter Munk Cardiac Centre, University of Toronto, Toronto, Ontario, Canada
| | - Matthew G. Doyle
- Division of Vascular Surgery, University Health Network, Peter Munk Cardiac Centre, University of Toronto, Toronto, Ontario, Canada
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Cristina H. Amon
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Thomas L. Forbes
- Division of Vascular Surgery, University Health Network, Peter Munk Cardiac Centre, University of Toronto, Toronto, Ontario, Canada
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Razavi M, Qiao Y, Thakor AS. Three-dimensional cryogels for biomedical applications. J Biomed Mater Res A 2019; 107:2736-2755. [PMID: 31408265 DOI: 10.1002/jbm.a.36777] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 08/01/2019] [Accepted: 08/07/2019] [Indexed: 12/12/2022]
Abstract
Cryogels are a subset of hydrogels synthesized under sub-zero temperatures: initially solvents undergo active freezing, which causes crystal formation, which is then followed by active melting to create interconnected supermacropores. Cryogels possess several attributes suited for their use as bioscaffolds, including physical resilience, bio-adaptability, and a macroporous architecture. Furthermore, their structure facilitates cellular migration, tissue-ingrowth, and diffusion of solutes, including nano- and micro-particle trafficking, into its supermacropores. Currently, subsets of cryogels made from both natural biopolymers such as gelatin, collagen, laminin, chitosan, silk fibroin, and agarose and/or synthetic biopolymers such as hydroxyethyl methacrylate, poly-vinyl alcohol, and poly(ethylene glycol) have been employed as 3D bioscaffolds. These cryogels have been used for different applications such as cartilage, bone, muscle, nerve, cardiovascular, and lung regeneration. Cryogels have also been used in wound healing, stem cell therapy, and diabetes cellular therapy. In this review, we summarize the synthesis protocol and properties of cryogels, evaluation techniques as well as current in vitro and in vivo cryogel applications. A discussion of the potential benefit of cryogels for future research and their application are also presented.
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Affiliation(s)
- Mehdi Razavi
- Interventional Regenerative Medicine and Imaging Laboratory, Department of Radiology, Stanford University, School of Medicine, Palo Alto, California
| | - Yang Qiao
- Texas A&M University College of Medicine, Bryan, Texas
| | - Avnesh S Thakor
- Interventional Regenerative Medicine and Imaging Laboratory, Department of Radiology, Stanford University, School of Medicine, Palo Alto, California
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Arjmandi M, Ramezani M. Mechanical and tribological assessment of silica nanoparticle-alginate-polyacrylamide nanocomposite hydrogels as a cartilage replacement. J Mech Behav Biomed Mater 2019; 95:196-204. [DOI: 10.1016/j.jmbbm.2019.04.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 03/04/2019] [Accepted: 04/11/2019] [Indexed: 12/19/2022]
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Pohan G, Chevallier P, Anderson DEJ, Tse JW, Yao Y, Hagen MW, Mantovani D, Hinds MT, Yim EKF. Luminal Plasma Treatment for Small Diameter Polyvinyl Alcohol Tubular Scaffolds. Front Bioeng Biotechnol 2019; 7:117. [PMID: 31192200 PMCID: PMC6541113 DOI: 10.3389/fbioe.2019.00117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 05/07/2019] [Indexed: 12/04/2022] Open
Abstract
Plasma-based surface modification is recognized as an effective way to activate biomaterial surfaces, and modulate their interactions with cells, extracellular matrix proteins, and other materials. However, treatment of a luminal surface of a tubular scaffold remains non-trivial to perform in small diameter tubes. Polyvinyl alcohol (PVA) hydrogel, which has been widely used for medical applications, lacks functional groups to mediate cell attachment. This poses an issue for vascular applications, as endothelialization in a vascular graft lumen is crucial to maintain long term graft patency. In this study, a Radio Frequency Glow Discharges (RFGD) treatment in the presence of NH3 was used to modify the luminal surface of 3-mm diameter dehydrated PVA vascular grafts. The grafted nitrogen containing functional groups demonstrated stability, and in vitro endothelialization was successfully maintained for at least 30 days. The plasma-modified PVA displayed a higher percentage of carbonyl groups over the untreated PVA control. Plasma treatment on PVA patterned with microtopographies was also studied, with only the concave microlenses topography demonstrating a significant increase in platelet adhesion. Thus, the study has shown the possibility of modifying a small diameter hydrogel tubular scaffold with the RFGD plasma treatment technique and demonstrated stability in ambient storage conditions for up to 30 days.
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Affiliation(s)
- Grace Pohan
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Pascale Chevallier
- Laboratory for Biomaterials and Bioengineering, CRC-I, Department of Mining, Metallurgical and Materials Engineering, CHU de Québec Research Center, Regenerative Medicine, Laval University, Québec City, QC, Canada
| | - Deirdre E J Anderson
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, United States
| | - John W Tse
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Yuan Yao
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Matthew W Hagen
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, United States
| | - Diego Mantovani
- Laboratory for Biomaterials and Bioengineering, CRC-I, Department of Mining, Metallurgical and Materials Engineering, CHU de Québec Research Center, Regenerative Medicine, Laval University, Québec City, QC, Canada
| | - Monica T Hinds
- Department of Biomedical Engineering, Oregon Health & Science University, Portland, OR, United States
| | - Evelyn K F Yim
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada
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Alexandrino-Junior F, Silva KGDHE, Freire MCLC, Lione VDOF, Cardoso EA, Marcelino HR, Genre J, Oliveira AGD, Egito ESTD. A Functional Wound Dressing as a Potential Treatment for Cutaneous Leishmaniasis. Pharmaceutics 2019; 11:E200. [PMID: 31052360 PMCID: PMC6571773 DOI: 10.3390/pharmaceutics11050200] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/18/2019] [Accepted: 03/21/2019] [Indexed: 12/24/2022] Open
Abstract
Cutaneous leishmaniasis (CL) is a parasitic disease characterized by progressive skin sores. Currently, treatments for CL are limited to parenteral administration of the drug, which presents severe adverse effects and low cure rates. Therefore, this study aimed to develop poly(vinyl-alcohol) (PVA) hydrogels containing Amphotericin B (AmB) intended for topical treatment of CL. Hydrogels were evaluated in vitro for their potential to eliminate promastigote forms of Leishmania spp., to prevent secondary infections, to maintain appropriate healing conditions, and to offer suitable biocompatibility. AmB was incorporated into the system in its non-crystalline state, allowing it to swell more and faster than the system without the drug. Furthermore, the AmB release profile showed a continuous and controlled behavior following Higuchi´s kinetic model. AmB-loaded-PVA-hydrogels (PVA-AmB) also showed efficient antifungal and leishmanicidal activity, no cytotoxic potential for VERO cells, microbial impermeability and water vapor permeability compatible with the healthy skin's physiological needs. Indeed, these results revealed the potential of PVA-AmB to prevent secondary infections and to maintain a favorable environment for the healing process. Hence, these results suggest that PVA-AmB could be a suitable and efficient new therapeutic approach for the topical treatment of CL.
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Affiliation(s)
- Francisco Alexandrino-Junior
- Programa de Pós-Graduação em Nanotecnologia Farmacêutica (PPgNANOFARMA), Universidade Federal do Rio Grande do Norte (UFRN), Nata/RN 59012-570, Brazil.
| | | | | | | | - Elisama Azevedo Cardoso
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro/RJ 21941-902, Brazil.
| | | | - Julieta Genre
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Norte (UFRN), Nata/RN 59012-570, Brazil.
| | - Anselmo Gomes de Oliveira
- Departamento de Fármacos e Medicamentos, Universidade Estadual Paulista (UNESP), Araraquara/SP 14800-903, Brazil.
| | - Eryvaldo Sócrates Tabosa do Egito
- Programa de Pós-Graduação em Nanotecnologia Farmacêutica (PPgNANOFARMA), Universidade Federal do Rio Grande do Norte (UFRN), Nata/RN 59012-570, Brazil.
- Faculdade de Farmácia, Universidade Federal do Rio Grande do Norte (UFRN), Nata/RN 59012-570, Brazil.
- Laboratório de Sistemas Dispersos (LaSiD), Departamento de Farmácia, Universidade Federal do Rio Grande do Norte (UFRN), Rua General Gustavo Cordeiro de Farias s/n, Petrópolis, Nata/RN 59012-570, Brazil.
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Fabrication of 3D freeform porous tubular constructs with mechanical flexibility mimicking that of soft vascular tissue. J Mech Behav Biomed Mater 2019; 91:193-201. [DOI: 10.1016/j.jmbbm.2018.12.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 11/17/2022]
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Irawan V, Sung TC, Higuchi A, Ikoma T. Collagen Scaffolds in Cartilage Tissue Engineering and Relevant Approaches for Future Development. Tissue Eng Regen Med 2018; 15:673-697. [PMID: 30603588 PMCID: PMC6250655 DOI: 10.1007/s13770-018-0135-9] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 05/30/2018] [Accepted: 06/15/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Cartilage tissue engineering (CTE) aims to obtain a structure mimicking native cartilage tissue through the combination of relevant cells, three-dimensional scaffolds, and extraneous signals. Implantation of 'matured' constructs is thus expected to provide solution for treating large injury of articular cartilage. Type I collagen is widely used as scaffolds for CTE products undergoing clinical trial, owing to its ubiquitous biocompatibility and vast clinical approval. However, the long-term performance of pure type I collagen scaffolds would suffer from its limited chondrogenic capacity and inferior mechanical properties. This paper aims to provide insights necessary for advancing type I collagen scaffolds in the CTE applications. METHODS Initially, the interactions of type I/II collagen with CTE-relevant cells [i.e., articular chondrocytes (ACs) and mesenchymal stem cells (MSCs)] are discussed. Next, the physical features and chemical composition of the scaffolds crucial to support chondrogenic activities of AC and MSC are highlighted. Attempts to optimize the collagen scaffolds by blending with natural/synthetic polymers are described. Hybrid strategy in which collagen and structural polymers are combined in non-blending manner is detailed. RESULTS Type I collagen is sufficient to support cellular activities of ACs and MSCs; however it shows limited chondrogenic performance than type II collagen. Nonetheless, type I collagen is the clinically feasible option since type II collagen shows arthritogenic potency. Physical features of scaffolds such as internal structure, pore size, stiffness, etc. are shown to be crucial in influencing the differentiation fate and secreting extracellular matrixes from ACs and MSCs. Collagen can be blended with native or synthetic polymer to improve the mechanical and bioactivities of final composites. However, the versatility of blending strategy is limited due to denaturation of type I collagen at harsh processing condition. Hybrid strategy is successful in maximizing bioactivity of collagen scaffolds and mechanical robustness of structural polymer. CONCLUSION Considering the previous improvements of physical and compositional properties of collagen scaffolds and recent manufacturing developments of structural polymer, it is concluded that hybrid strategy is a promising approach to advance further collagen-based scaffolds in CTE.
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Affiliation(s)
- Vincent Irawan
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 2 Chome-12-1, Meguro-ku, Tokyo, 152-8550 Japan
| | - Tzu-Cheng Sung
- Department of Chemical and Materials Engineering, National Central University, No. 300 Jung Da Rd., Chung-Li, Taoyuan, 320 Taiwan
| | - Akon Higuchi
- Department of Chemical and Materials Engineering, National Central University, No. 300 Jung Da Rd., Chung-Li, Taoyuan, 320 Taiwan
| | - Toshiyuki Ikoma
- Department of Materials Science and Engineering, Tokyo Institute of Technology, 2 Chome-12-1, Meguro-ku, Tokyo, 152-8550 Japan
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Atlan M, Simon-Yarza T, Ino JM, Hunsinger V, Corté L, Ou P, Aid-Launais R, Chaouat M, Letourneur D. Design, characterization and in vivo performance of synthetic 2 mm-diameter vessel grafts made of PVA-gelatin blends. Sci Rep 2018; 8:7417. [PMID: 29743525 PMCID: PMC5943294 DOI: 10.1038/s41598-018-25703-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 04/24/2018] [Indexed: 01/06/2023] Open
Abstract
Since the development of the first vascular grafts, fabrication of vessel replacements with diameters smaller than 6 mm remains a challenge. The present work aimed to develop PVA (poly (vinyl alcohol))-gelatin hybrids as tubes suitable for replacement of very small vessels and to evaluate their performance using a rat abdominal aorta interposition model. PVA-gelatin hybrid tubes with internal and external diameters of 1.4 mm and 1.8 mm, respectively, composed of 4 different gelatin ratios were prepared using a one-step strategy with both chemical and physical crosslinking. By 3D Time of Flight MRI, Doppler-Ultrasound, Computed Tomography angiography and histology, we demonstrated good patency rates with the 1% gelatin composition until the end of the study at 3 months (50% compared to 0% of PVA control grafts). A reduction of the patency rate during the time of implantation suggested some loss of properties of the hybrid material in vivo, further confirmed by mechanical evaluation until one year. In particular, stiffening and reduction of compliance of the PVA-gelatin grafts was demonstrated, which might explain the observed long-term changes in patency rate. These encouraging results confirm the potential of PVA-gelatin hybrids as ready-to-use vascular grafts for very small vessel replacement.
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Affiliation(s)
- M Atlan
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France. .,Faculty of Medicine, University Pierre et Marie Curie, Plastic Surgery Department, Hôpital Tenon, Paris, France.
| | - T Simon-Yarza
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France.
| | - J M Ino
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France
| | - V Hunsinger
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France.,Faculty of Medicine, University Pierre et Marie Curie, Plastic Surgery Department, Hôpital Tenon, Paris, France
| | - L Corté
- MINES ParisTech, PSL Research University, MAT - Centre des Matériaux, CNRS UMR 7633, BP 87 91003, Evry, France.,ESPCI-Paris, PSL Research University, Matière Molle et Chimie, CNRS UMR 7167, Paris, 75005, France
| | - P Ou
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France
| | - R Aid-Launais
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France.,FRIM, INSERM UMS 034 Paris Diderot University, X. Bichat Hospital, 75018, Paris, France
| | - M Chaouat
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France.,Plastic Surgery Department, Burn Unit, Paris Diderot University, Hôpital Saint Louis, Paris, France
| | - D Letourneur
- INSERM U1148, Laboratory for Vascular Translational Science, X. Bichat Hospital, Paris Diderot University, Paris 13 University, 75018, Paris, France
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Tribological properties of PVA/PVP blend hydrogels against articular cartilage. J Mech Behav Biomed Mater 2018; 78:36-45. [DOI: 10.1016/j.jmbbm.2017.10.027] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 10/16/2017] [Accepted: 10/23/2017] [Indexed: 11/21/2022]
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Affiliation(s)
- Mirela Teodorescu
- Laboratory of Electroactive Polymers and Plasmochemistry, “Petru Poni” Institute of Macromolecular Chemistry, 41-A Grigore Ghica Voda Alley, Iasi, Romania
| | - Maria Bercea
- Laboratory of Electroactive Polymers and Plasmochemistry, “Petru Poni” Institute of Macromolecular Chemistry, 41-A Grigore Ghica Voda Alley, Iasi, Romania
| | - Simona Morariu
- Laboratory of Electroactive Polymers and Plasmochemistry, “Petru Poni” Institute of Macromolecular Chemistry, 41-A Grigore Ghica Voda Alley, Iasi, Romania
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Zhang J, Xu WR, Zhang Y, Li W, Hu J, Zheng F, Wu Y. Liquefied chitin/polyvinyl alcohol based blend membranes: Preparation and characterization and antibacterial activity. Carbohydr Polym 2018; 180:175-181. [DOI: 10.1016/j.carbpol.2017.10.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 09/11/2017] [Accepted: 10/03/2017] [Indexed: 10/18/2022]
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Nachlas ALY, Li S, Davis ME. Developing a Clinically Relevant Tissue Engineered Heart Valve-A Review of Current Approaches. Adv Healthc Mater 2017; 6. [PMID: 29171921 DOI: 10.1002/adhm.201700918] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/25/2017] [Indexed: 11/08/2022]
Abstract
Tissue engineered heart valves (TEHVs) have the potential to address the shortcomings of current implants through the combination of cells and bioactive biomaterials that promote growth and proper mechanical function in physiological conditions. The ideal TEHV should be anti-thrombogenic, biocompatible, durable, and resistant to calcification, and should exhibit a physiological hemodynamic profile. In addition, TEHVs may possess the capability to integrate and grow with somatic growth, eliminating the need for multiple surgeries children must undergo. Thus, this review assesses clinically available heart valve prostheses, outlines the design criteria for developing a heart valve, and evaluates three types of biomaterials (decellularized, natural, and synthetic) for tissue engineering heart valves. While significant progress has been made in biomaterials and fabrication techniques, a viable tissue engineered heart valve has yet to be translated into a clinical product. Thus, current strategies and future perspectives are also discussed to facilitate the development of new approaches and considerations for heart valve tissue engineering.
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Affiliation(s)
- Aline L. Y. Nachlas
- Wallace H Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA
| | - Siyi Li
- Wallace H Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA
| | - Michael E. Davis
- Wallace H Coulter Department of Biomedical Engineering Georgia Institute of Technology and Emory University Atlanta GA 30332 USA
- Children's Heart Research & Outcomes (HeRO) Center Children's Healthcare of Atlanta & Emory University Atlanta GA 30322 USA
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50
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Calcium phosphate/polyvinyl alcohol composite hydrogels: A review on the freeze-thawing synthesis approach and applications in regenerative medicine. Eur Polym J 2017. [DOI: 10.1016/j.eurpolymj.2017.08.048] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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