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Extrusion-Based Technology in Additive Manufacturing: A Comprehensive Review. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2022. [DOI: 10.1007/s13369-022-07539-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Printing Technologies as an Emerging Approach in Gas Sensors: Survey of Literature. SENSORS 2022; 22:s22093473. [PMID: 35591162 PMCID: PMC9102873 DOI: 10.3390/s22093473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 02/04/2023]
Abstract
Herein, we review printing technologies which are commonly approbated at recent time in the course of fabricating gas sensors and multisensor arrays, mainly of chemiresistive type. The most important characteristics of the receptor materials, which need to be addressed in order to achieve a high efficiency of chemisensor devices, are considered. The printing technologies are comparatively analyzed with regard to, (i) the rheological properties of the employed inks representing both reagent solutions or organometallic precursors and disperse systems, (ii) the printing speed and resolution, and (iii) the thickness of the formed coatings to highlight benefits and drawbacks of the methods. Particular attention is given to protocols suitable for manufacturing single miniature devices with unique characteristics under a large-scale production of gas sensors where the receptor materials could be rather quickly tuned to modify their geometry and morphology. We address the most convenient approaches to the rapid printing single-crystal multisensor arrays at lab-on-chip paradigm with sufficiently high resolution, employing receptor layers with various chemical composition which could replace in nearest future the single-sensor units for advancing a selectivity.
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3D Printed and Conventional Membranes—A Review. Polymers (Basel) 2022; 14:polym14051023. [PMID: 35267846 PMCID: PMC8914971 DOI: 10.3390/polym14051023] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 02/23/2022] [Accepted: 03/01/2022] [Indexed: 12/15/2022] Open
Abstract
Polymer membranes are central to the proper operation of several processes used in a wide range of applications. The production of these membranes relies on processes such as phase inversion, stretching, track etching, sintering, or electrospinning. A novel and competitive strategy in membrane production is the use of additive manufacturing that enables the easier manufacture of tailored membranes. To achieve the future development of better membranes, it is necessary to compare this novel production process to that of more conventional techniques, and clarify the advantages and disadvantages. This review article compares a conventional method of manufacturing polymer membranes to additive manufacturing. A review of 3D printed membranes is also done to give researchers a reference guide. Membranes from these two approaches were compared in terms of cost, materials, structures, properties, performance. and environmental impact. Results show that very few membrane materials are used as 3D-printed membranes. Such membranes showed acceptable performance, better structures, and less environmental impact compared with those of conventional membranes.
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Qian X, Ostwal M, Asatekin A, Geise GM, Smith ZP, Phillip WA, Lively RP, McCutcheon JR. A critical review and commentary on recent progress of additive manufacturing and its impact on membrane technology. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2021.120041] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Effect of Double-Sided 3D Patterned Cathode Catalyst Layers on Polymer Electrolyte Fuel Cell Performance. ENERGIES 2022. [DOI: 10.3390/en15031179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Optimization of the structure of cathode catalyst layers (CCLs) for promoting the transfer of reactants and products in polymer electrolyte fuel cells (PEFCs) is important for improving the cell performance. In this study, using theoretical equations, we confirmed that the shortened proton conduction path in the ionomer layer (IL) with a 3D-patterned structure, compared to that in the IL with a flat-patterned structure, can improve the cell performance. We experimentally investigated the effect of the IL with a 3D-patterned structure included in the CCLs on the cell performance. Based on the combination of the flat- or 3D-pattern of the IL and the catalyst layer (CL), the samples were categorized as Str. 1 (3D-patterned CL without IL), Str. 2 (flat-patterned IL and CL), Str. 3 (3D-patterned IL and flat-patterned CL), and Str. 4 (3D-patterned IL and CL). All of the samples had different morphologies. According to the I–V curves and impedance spectra data acquired at 80 °C and 40% relative humidity, Str. 4 showed superior cell performance relative to those of the other CCLs. These results indicate that the structure of Str. 4 enhanced the proton conductivity at a low humidity at which proton conduction is usually poor, thereby resulting in improved cell performance.
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Zarepour A, Hooshmand S, Gökmen A, Zarrabi A, Mostafavi E. Spinal Cord Injury Management through the Combination of Stem Cells and Implantable 3D Bioprinted Platforms. Cells 2021; 10:cells10113189. [PMID: 34831412 PMCID: PMC8620694 DOI: 10.3390/cells10113189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/01/2021] [Accepted: 11/09/2021] [Indexed: 12/17/2022] Open
Abstract
Spinal cord injury (SCI) has a major impact on affected patients due to its pathological consequences and absence of capacity for self-repair. Currently available therapies are unable to restore lost neural functions. Thus, there is a pressing need to develop novel treatments that will promote functional repair after SCI. Several experimental approaches have been explored to tackle SCI, including the combination of stem cells and 3D bioprinting. Implanted multipotent stem cells with self-renewing capacity and the ability to differentiate to a diversity of cell types are promising candidates for replacing dead cells in injured sites and restoring disrupted neural circuits. However, implanted stem cells need protection from the inflammatory agents in the injured area and support to guide them to appropriate differentiation. Not only are 3D bioprinted scaffolds able to protect stem cells, but they can also promote their differentiation and functional integration at the site of injury. In this review, we showcase some recent advances in the use of stem cells for the treatment of SCI, different types of 3D bioprinting methods, and the combined application of stem cells and 3D bioprinting technique for effective repair of SCI.
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Affiliation(s)
- Atefeh Zarepour
- Department of Biomedical Engineering, Faculty of Engineering and Natural Sciences, Istinye University, Istanbul 34396, Turkey;
| | - Sara Hooshmand
- Nanotechnology Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey;
| | - Aylin Gökmen
- Molecular Biology and Genetics Department, Faculty of Engineering and Natural Sciences, Bahcesehir University, Istanbul 34353, Turkey;
| | - Ali Zarrabi
- Department of Biomedical Engineering, Faculty of Engineering and Natural Sciences, Istinye University, Istanbul 34396, Turkey;
- Nanotechnology Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey;
- Correspondence: (A.Z.); or (E.M.); Tel.: +90-537-731-0182 (A.Z.); +1-617-5130314 (E.M.)
| | - Ebrahim Mostafavi
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, USA
- Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
- Correspondence: (A.Z.); or (E.M.); Tel.: +90-537-731-0182 (A.Z.); +1-617-5130314 (E.M.)
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Erokhin KS, Gordeev EG, Samoylenko DE, Rodygin KS, Ananikov VP. 3D Printing to Increase the Flexibility of the Chemical Synthesis of Biologically Active Molecules: Design of On-Demand Gas Generation Reactors. Int J Mol Sci 2021; 22:9919. [PMID: 34576082 PMCID: PMC8472564 DOI: 10.3390/ijms22189919] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/08/2021] [Accepted: 09/10/2021] [Indexed: 11/16/2022] Open
Abstract
The development of new drugs is accelerated by rapid access to functionalized and D-labeled molecules with improved activity and pharmacokinetic profiles. Diverse synthetic procedures often involve the usage of gaseous reagents, which can be a difficult task due to the requirement of a dedicated laboratory setup. Here, we developed a special reactor for the on-demand production of gases actively utilized in organic synthesis (C2H2, H2, C2D2, D2, and CO2) that completely eliminates the need for high-pressure equipment and allows for integrating gas generation into advanced laboratory practice. The reactor was developed by computer-aided design and manufactured using a conventional 3D printer with polypropylene and nylon filled with carbon fibers as materials. The implementation of the reactor was demonstrated in representative reactions with acetylene, such as atom-economic nucleophilic addition (conversions of 19-99%) and nickel-catalyzed S-functionalization (yields 74-99%). One of the most important advantages of the reactor is the ability to generate deuterated acetylene (C2D2) and deuterium gas (D2), which was used for highly significant, atom-economic and cost-efficient deuterium labeling of S,O-vinyl derivatives (yield 68-94%). Successful examples of their use in organic synthesis are provided to synthesize building blocks of heteroatom-functionalized and D-labeled biologically active organic molecules.
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Affiliation(s)
- Kirill S. Erokhin
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991 Moscow, Russia; (K.S.E.); (E.G.G.); (K.S.R.)
| | - Evgeniy G. Gordeev
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991 Moscow, Russia; (K.S.E.); (E.G.G.); (K.S.R.)
| | - Dmitriy E. Samoylenko
- Institute of Chemistry, Saint Petersburg State University, Universitetsky Prospect 26, 198504 Peterhof, Russia;
| | - Konstantin S. Rodygin
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991 Moscow, Russia; (K.S.E.); (E.G.G.); (K.S.R.)
- Institute of Chemistry, Saint Petersburg State University, Universitetsky Prospect 26, 198504 Peterhof, Russia;
| | - Valentine P. Ananikov
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences, Leninsky Prospect 47, 119991 Moscow, Russia; (K.S.E.); (E.G.G.); (K.S.R.)
- Institute of Chemistry, Saint Petersburg State University, Universitetsky Prospect 26, 198504 Peterhof, Russia;
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Lee WJ, Goh PS, Lau WJ, Ismail AF, Hilal N. Green Approaches for Sustainable Development of Liquid Separation Membrane. MEMBRANES 2021; 11:235. [PMID: 33806115 PMCID: PMC8064480 DOI: 10.3390/membranes11040235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/21/2021] [Accepted: 03/22/2021] [Indexed: 11/30/2022]
Abstract
Water constitutes one of the basic necessities of life. Around 71% of the Earth is covered by water, however, not all of it is readily available as fresh water for daily consumption. Fresh water scarcity is a chronic issue which poses a threat to all living things on Earth. Seawater, as a natural resource abundantly available all around the world, is a potential water source to fulfil the increasing water demand. Climate-independent seawater desalination has been touted as a crucial alternative to provide fresh water. While the membrane-based desalination process continues to dominate the global desalination market, the currently employed membrane fabrication materials and processes inevitably bring adverse impacts to the environment. This review aims to elucidate and provide a comprehensive outlook of the recent efforts based on greener approaches used for desalination membrane fabrication, which paves the way towards achieving sustainable and eco-friendly processes. Membrane fabrication using green chemistry effectively minimizes the generation of hazardous compounds during membrane preparation. The future trends and recommendations which could potentially be beneficial for researchers in this field are also highlighted.
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Affiliation(s)
- Wei Jie Lee
- Advanced Membrane Technology Research Centre, School of Chemical & Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johore, Malaysia; (W.J.L.); (W.J.L.); (A.F.I.)
| | - Pei Sean Goh
- Advanced Membrane Technology Research Centre, School of Chemical & Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johore, Malaysia; (W.J.L.); (W.J.L.); (A.F.I.)
| | - Woei Jye Lau
- Advanced Membrane Technology Research Centre, School of Chemical & Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johore, Malaysia; (W.J.L.); (W.J.L.); (A.F.I.)
| | - Ahmad Fauzi Ismail
- Advanced Membrane Technology Research Centre, School of Chemical & Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johore, Malaysia; (W.J.L.); (W.J.L.); (A.F.I.)
| | - Nidal Hilal
- Water Research Centre, New York University Abu Dhabi (NYUAD), Saadiyat Marina District, Abu Dhabi PO Box 129188, United Arab Emirates
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Additive manufacturing of the core template for the fabrication of an artificial blood vessel: the relationship between the extruded deposition diameter and the filament/nozzle transition ratio. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 118:111406. [PMID: 33255009 DOI: 10.1016/j.msec.2020.111406] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/22/2020] [Accepted: 08/19/2020] [Indexed: 12/14/2022]
Abstract
An artificial blood vessel with a tubular structure was additively manufactured via fused deposition modeling (FDM) starting from a single strand of polyvinyl alcohol (PVA) filament coated with a specific thickness of biocompatible polydimethylsiloxane (PDMS), followed by removal of the inner core via hydrogen peroxide leaching under sonication. In particular, we examined the relationship between the extruded deposition diameter and the filament migration speed/nozzle control speed (referred to as the filament/nozzle transition ratio), which is almost independent of the extruded deposition flow rate due to the weak die-swelling and memory effects of the extruded PVA arising from its intrinsically low viscoelasticity. The chemical stability of the PDMS during sonication in the hydrogen peroxide solution was then determined by spectroscopic techniques. The PDMS displayed no mechanical degradation in the hydrogen peroxide solution, resulting in similar fracture elongation and yield strength to those of the pristine specimen without the leaching treatment. As a further advantage, the inside surface of the PDMS was smooth regardless of the hydrogen peroxide leaching under sonication. The potential application of the as-developed scaffold in soft tissue engineering (particularly that involving vascular tissue regeneration) was demonstrated by the successful transplantation of the artificial blood vessel in a right-hand surgical replica used in a clinical simulation.
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Serris I, Serris P, Frey KM, Cho H. Development of 3D-Printed Layered PLGA Films for Drug Delivery and Evaluation of Drug Release Behaviors. AAPS PharmSciTech 2020; 21:256. [PMID: 32888114 DOI: 10.1208/s12249-020-01790-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/17/2020] [Indexed: 02/07/2023] Open
Abstract
3D printing has been widely used to rapidly manufacture a variety of solid dosage forms on-demand, without sacrificing precision. This study used extrusion-based 3D printing to prepare single-layered, tri-layered, and core-in-shell poly(lactic-co-glycolic acid) (PLGA) films carrying paclitaxel and rapamycin in combination or lidocaine alone. Each layer was composed of either low molecular weight (MW) PLGA or high MW PLGA. In vitro drug release kinetics of paclitaxel, rapamycin, and lidocaine for PLGA films were assessed and compared with PLGA-polyethylene glycol (PEG)-PLGA hydrogel discs. Regardless of the structure of PLGA film, paclitaxel (half-time: 54-63 days) was released faster than when compared with rapamycin (half-time: 74-80 days). In contrast, single-layered PLGA-PEG-PLGA discs released rapamycin (half-time 5.7 h) at a more rapid rate than paclitaxel (half-time: 7.3 h). Single-layered PLGA-PEG-PLGA discs enabled a faster drug release than PLGA films, noting that the disc matrices dissolve in water in 24 h. Similarly, lidocaine incorporated in PLGA films (half-time: 13-36 days) exhibited slower release patterns than that in PLGA-PEG-PLGA discs (half-time: 2.6 h). In vitro drug release patterns were explained using molecular models that simulate drug-polymer interactions. Analysis of models suggested that drug-polymer interactions, location of each drug in the polymeric matrix, and solubility of drugs in water were major factors that determine drug release behaviors from the polymeric films and discs.
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11
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Boydston AJ, Cui J, Lee CU, Lynde BE, Schilling CA. 100th Anniversary of Macromolecular Science Viewpoint: Integrating Chemistry and Engineering to Enable Additive Manufacturing with High-Performance Polymers. ACS Macro Lett 2020; 9:1119-1129. [PMID: 35653212 DOI: 10.1021/acsmacrolett.0c00390] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Additive manufacturing (AM) with high-performance polymers (HPPs) represents simultaneously one of the most desirable and challenging feats in the AM arena. The very properties that make HPPs so attractive in a broad range of applications also make them nearly impossible to process using common AM equipment. Furthermore, when AM is achieved, it often brings the caveat of compromised mechanical properties of the final parts, in comparison with those made via injection molding. The demand to have advanced fabrication methods, rapid prototyping, and customization of parts while maintaining high performance in the finished products has inspired creative innovations that integrate chemical synthesis, materials science, mechanical engineering, and other fields into a multidisciplinary approach to advance AM with the seemingly "unprintable" HPPs. In this Viewpoint, we summarize several standout developments in the area and offer our perspective on future directions and challenges.
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Erokhin KS, Gordeev EG, Ananikov VP. Revealing interactions of layered polymeric materials at solid-liquid interface for building solvent compatibility charts for 3D printing applications. Sci Rep 2019; 9:20177. [PMID: 31882642 PMCID: PMC6934857 DOI: 10.1038/s41598-019-56350-w] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 12/11/2019] [Indexed: 11/09/2022] Open
Abstract
Poor stability of 3D printed plastic objects in a number of solvents limits several important applications in engineering, chemistry and biology. Due to layered type of assembling, 3D-printed surfaces possess rather different properties as compared to bulk surfaces made by other methods. Here we study fundamental interactions at the solid-liquid interface and evaluate polymeric materials towards advanced additive manufacturing. A simple and universal stability test was developed for 3D printed parts and applied to a variety of thermoplastics. Specific modes of resistance/destruction were described for different plastics and their compatibility to a representative scope of solvents (aqueous and organic) was evaluated. Classification and characterization of destruction modes for a wide range of conditions (including geometry and 3D printing parameters) were carried out. Key factors of tolerance to solvent media were investigated by electron microscopy. We show that the overall stability and the mode of destruction depend on chemical properties of the polymer and the nature of interactions at the solid-liquid interface. Importantly, stability also depends on the layered microstructure of the sample, which is defined by 3D printing parameters. Developed solvent compatibility charts for a wide range of polymeric materials (ABS, PLA, PLA-Cu, PETG, SBS, Ceramo, HIPS, Primalloy, Photoresin, Nylon, Nylon-C, POM, PE, PP) and solvents represent an important benchmark for practical applications.
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Affiliation(s)
- Kirill S Erokhin
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia
| | - Evgeniy G Gordeev
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia
| | - Valentine P Ananikov
- Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky prospekt 47, Moscow, 119991, Russia.
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Advances in bioprinting using additive manufacturing. Eur J Pharm Sci 2019; 143:105167. [PMID: 31778785 DOI: 10.1016/j.ejps.2019.105167] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/22/2019] [Accepted: 11/25/2019] [Indexed: 01/27/2023]
Abstract
Since its conception in the 1980's, several advances in the field of additive manufacturing have led to exploration of alternate as well as combination biomaterials. These progresses have directed the use of 3D printing in wider applications such as printing of dermal layers, cartilage, bone defects, and surgical implants. Furthermore, the incorporation of live and functional cells with or atop biomaterials has laid the foundation for its use in tissue engineering. The purpose of this review is to summarize the advances in 3D printing and bioprinting of several types of tissues such as skin, cartilage, bones, and cardiac valves. This review will address the current 3D technologies used in tissue construction and study the biomaterials being investigated. There are several requirements that need to be addressed, in order to reconstruct functional tissue such as mechanical strength, porosity of the replicate and cellular incorporation. Researchers have focused their studies to answer questions regarding these requirements.
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Koh LB, Zuo K, Kumar GP, Ding X, Leo HL, Cui F, Charles CJ, Yang YY, Yim EKF, Ho P. Optimization of a Novel Preferential Covered Stent through Bench Experiments and in Vitro Platelet Activation Studies. ACS Biomater Sci Eng 2019; 5:6216-6230. [PMID: 33405529 DOI: 10.1021/acsbiomaterials.9b00763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bare metal stenting (BMS) does not adequately address the atheroembolic characteristic of carotid artery stenosis. While simple covered stents (CS) may prevent dislodged fragments of the atherosclerotic plaque from entering the blood stream, they also block blood flow into the major branches of the artery alongside the lesion, which is not desirable. Preferential covered stents (PCS) behave as a covered stent in a tubular part of a vessel but maintain side-branch flow over the bifurcation region by means of slits in the membrane. Stent design, membrane material, and slits configuration are the three main components contributing to stent performance. Optimization of PCS designs was conducted and tested. METHODS A newly designed BMS was developed and compared to a commercially available peripheral stent. Two materials (expanded poly(tetrafluoroethylene)) and silicone polyurethane co-polymers (Elast-eon E2A) were used as stent coverings with slits applied using various cutting methods to form the PCS. These PCS samples were tested for physical resilience, flexibility, ability to preserve side-branch flow, slit edge roughness, and platelet activation. RESULTS Fabrication of E2A-coated stents required pretreatment of the stent with poly(ethylene glycol) to achieve firm attachment. The newly designed BMS with nine crowns design and larger cell size showed higher flexibility than commercially available stents. A combination of a larger stent cell size, E2A membrane coating, and three slits per stent cell unit configuration resulted in preserved side-branch flow similar to physiological conditions in the flow experiment. Slit edge roughness changed with different cutting methods and laser machine cutting parameters. In vitro studies showed platelet activation was minimal with lower slit edge roughness samples. CONCLUSION An optimized PCS prototype was developed consisting of a newly designed stent, E2A membrane, and a three-slit pattern created by specific femtosecond laser cutting.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Evelyn K F Yim
- Department of Chemical Engineering, University of Waterloo, Ontario, Canada
| | - Pei Ho
- Department of Cardiac, Thoracic & Vascular Surgery, National University Health System, Singapore
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Strehmel B, Schmitz C, Cremanns K, Göttert J. Photochemistry with Cyanines in the Near Infrared: A Step to Chemistry 4.0 Technologies. Chemistry 2019; 25:12855-12864. [PMID: 31270883 PMCID: PMC6851862 DOI: 10.1002/chem.201901746] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/30/2019] [Indexed: 11/08/2022]
Abstract
Cyanines covering the absorption in the near infrared (NIR) are attractive for distinct applications. They can interact either with lasers exhibiting line-shaped focus emitting at both 808 and 980 nm or bright high intensity NIR-LEDs with 805 nm emission, respectively. This is drawing attention to Industry 4.0 applications. The major deactivation occurs through a non-radiative process resulting in the release of heat into the surrounding, although a small fraction of radiative deactivation also takes place. Most of these NIR-sensitive systems possess an internal activation barrier to react in a photonic process with initiators resulting in the generation of reactive radicals and acidic cations. Thus, the heat released by the NIR absorber helps to bring the system, consisting of an NIR sensitizer and initiator, above such internal barriers. Molecular design strategies making these systems more compatible with distinct applications in a certain oleophilic surrounding are considered as a big challenge. This includes variations of the molecular pattern and counter ions derived from super acids exhibiting low coordinating properties. Further discussion focusses on the use of such systems in Chemistry 4.0 related applications. Intelligent software tools help to improve and optimize these systems combining chemistry, engineering based on high-throughput formulation screening (HTFS) technologies, and machine learning algorithms to open up novel solutions in material sciences.
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Affiliation(s)
- Bernd Strehmel
- Department of Chemistry and Institute for Coatings and Surface ChemistryNiederrhein University of Applied SciencesAdlerstr. 147798KrefeldGermany
| | - Christian Schmitz
- Department of Chemistry and Institute for Coatings and Surface ChemistryNiederrhein University of Applied SciencesAdlerstr. 147798KrefeldGermany
| | - Kevin Cremanns
- Department of Mechanical EngineeringInstitute of Modelling and High-Performance ComputingNiederrhein University of Applied SciencesReinarzstr. 4947805KrefeldGermany
| | - Jost Göttert
- Department of Electrical Engineering and Computer SciencesHIT-Hochschule Niederrhein Institute of Surface TechnologyNiederrhein University of Applied SciencesReinarzstr. 4947805KrefeldGermany
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