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Wang XQ, Xie AQ, Cao P, Yang J, Ong WL, Zhang KQ, Ho GW. Structuring and Shaping of Mechanically Robust and Functional Hydrogels toward Wearable and Implantable Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2309952. [PMID: 38389497 DOI: 10.1002/adma.202309952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 02/16/2024] [Indexed: 02/24/2024]
Abstract
Hydrogels possess unique features such as softness, wetness, responsiveness, and biocompatibility, making them highly suitable for biointegrated applications that have close interactions with living organisms. However, conventional man-made hydrogels are usually soft and brittle, making them inferior to the mechanically robust biological hydrogels. To ensure reliable and durable operation of biointegrated wearable and implantable devices, mechanical matching and shape adaptivity of hydrogels to tissues and organs are essential. Recent advances in polymer science and processing technologies have enabled mechanical engineering and shaping of hydrogels for various biointegrated applications. In this review, polymer network structuring strategies at micro/nanoscales for toughening hydrogels are summarized, and representative mechanical functionalities that exist in biological materials but are not easily achieved in synthetic hydrogels are further discussed. Three categories of processing technologies, namely, 3D printing, spinning, and coating for fabrication of tough hydrogel constructs with complex shapes are reviewed, and the corresponding hydrogel toughening strategies are also highlighted. These developments enable adaptive fabrication of mechanically robust and functional hydrogel devices, and promote application of hydrogels in the fields of biomedical engineering, bioelectronics, and soft robotics.
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Affiliation(s)
- Xiao-Qiao Wang
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, China
| | - An-Quan Xie
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, China
| | - Pengle Cao
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, China
| | - Jian Yang
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, China
| | - Wei Li Ong
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
| | - Ke-Qin Zhang
- National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, China
| | - Ghim Wei Ho
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore
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Ansari MJ, Rajendran RR, Mohanto S, Agarwal U, Panda K, Dhotre K, Manne R, Deepak A, Zafar A, Yasir M, Pramanik S. Poly( N-isopropylacrylamide)-Based Hydrogels for Biomedical Applications: A Review of the State-of-the-Art. Gels 2022; 8:454. [PMID: 35877539 PMCID: PMC9323937 DOI: 10.3390/gels8070454] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/08/2022] [Accepted: 07/08/2022] [Indexed: 12/21/2022] Open
Abstract
A prominent research topic in contemporary advanced functional materials science is the production of smart materials based on polymers that may independently adjust their physical and/or chemical characteristics when subjected to external stimuli. Smart hydrogels based on poly(N-isopropylacrylamide) (PNIPAM) demonstrate distinct thermoresponsive features close to a lower critical solution temperature (LCST) that enhance their capability in various biomedical applications such as drug delivery, tissue engineering, and wound dressings. Nevertheless, they have intrinsic shortcomings such as poor mechanical properties, limited loading capacity of actives, and poor biodegradability. Formulation of PNIPAM with diverse functional constituents to develop hydrogel composites is an efficient scheme to overcome these defects, which can significantly help for practicable application. This review reports on the latest developments in functional PNIPAM-based smart hydrogels for various biomedical applications. The first section describes the properties of PNIPAM-based hydrogels, followed by potential applications in diverse fields. Ultimately, this review summarizes the challenges and opportunities in this emerging area of research and development concerning this fascinating polymer-based system deep-rooted in chemistry and material science.
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Affiliation(s)
- Mohammad Javed Ansari
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
| | - Rahul R. Rajendran
- Department of Mechanical Engineering and Mechanics, Lehigh University, 19 Memorial Drive West, Bethlehem, PA 18015, USA;
| | - Sourav Mohanto
- Department of Pharmaceutics, Yenepoya Pharmacy College and Research Centre, Yenepoya (Deemed to be University), Mangalore 575018, Karnataka, India;
| | - Unnati Agarwal
- School of Bioengineering and Biosciences, Lovely Professional University, Jalandhar-Delhi, Grand Trunk Road, Phagwara 144001, Punjab, India;
| | - Kingshuk Panda
- Department of Applied Microbiology, Vellore Institute of Technology, School of Bioscience and Technology, Vellore 632014, Tamilnadu, India;
| | - Kishore Dhotre
- I.C.M.R.—National Institute of Virology, Pune 411021, Maharashtra, India;
| | - Ravi Manne
- Chemtex Environmental Lab, Quality Control and Assurance Department, 3082 25th Street, Port Arthur, TX 77642, USA;
| | - A. Deepak
- Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai 600124, Tamil Nadu, India;
| | - Ameeduzzafar Zafar
- Department of Pharmaceutics, College of Pharmacy, Jouf University, Sakaka 72341, Saudi Arabia; or
| | - Mohd Yasir
- Department of Pharmacy, College of Health Science, Arsi University, Asella 396, Ethiopia;
| | - Sheersha Pramanik
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India
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Qiu C, Sun W, Wang T, Tong Z. Phase separation of chemically crosslinked poly(n-butyl methacrylate-co-methacrylic acid) in mixtures of N,N-dimethyl formamide and water. POLYMER 2022. [DOI: 10.1016/j.polymer.2022.125009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Şahin FC, Şimşek C, Erbil C. Study on preparation, compression strength and theophylline/diclofenac sodium release ability of NIPAAm/DMAPMAAm hydrogels. JOURNAL OF BIOMATERIALS SCIENCE. POLYMER EDITION 2021; 32:2267-2292. [PMID: 34436978 DOI: 10.1080/09205063.2021.1967700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
The present study was undertaken to investigate the effect of the composition of the polymerization medium and the type of drug/drug loading process on the mechanical strengths and release profiles of poly(N-isopropylacrylamide-co-N-[3-(dimethylamino)propyl] methacrylamide) P(NIPAAm-co-DMAPMAAm) hydrogels. In line with this goal firstly, the temperature- and pH-responsive hydrogels of NIPAAm and DMAPMAAm were synthesized in three different media at 60 °C: pH 7.4 phosphate-buffered saline (PBS), pH 7.4 phosphate buffer without NaCl/KCl (PB), and distilled-deionized water (pH ≈ 5.5 DDW). The result is that the presence of anionic species such as phosphate (HPO42-/H2PO4-) and chloride (Cl-) ions in the solution affects on their basic network properties such as volumetric swelling ratio and compression modulus. To evaluate their intermolecular interactions with protonated DMAPMAAm units and drug molecules, depending on composition, type of loading process and drug structure, each of the hydrogels was loaded with diclofenac sodium (DFNa) and theophylline (Thp) by using both diffusion and in situ loading methods. DFNa and Thp release profiles in pH 7.4 PBS at 37 °C were analysed by using zero-order, first-order, Higuchi, Korsmeyer-Peppas, and Peppas-Sahlin models. It has been observed that for the first 60% of DFNa and Thp releases from P(NIPAAm-co-DMAPMAAm) hydrogels synthesized in PB at 60 °C, the contribution of the chain relaxation for the copolymer hydrogels loaded during gelation process was higher than the ones loaded by diffusion process.
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Affiliation(s)
| | - Ceyda Şimşek
- Chemistry Department, Istanbul Technical University, Istanbul, Turkey
| | - Candan Erbil
- Chemistry Department, Istanbul Technical University, Istanbul, Turkey
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5
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Liu M, Wu C, Ke L, Li Z, Wu YL. Emerging Biomaterials-Based Strategies for Inhibiting Vasculature Function in Cancer Therapy. SMALL METHODS 2021; 5:e2100347. [PMID: 34927997 DOI: 10.1002/smtd.202100347] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/20/2021] [Indexed: 06/14/2023]
Abstract
The constant feeding of oxygen and nutrients through the blood vasculature has a vital role in maintaining tumor growth. Interestingly, recent endeavors have shown that nanotherapeutics with the strategy to block tumor blood vessels feeding nutrients and oxygen for starvation therapy can be helpful in cancer treatment. However, this field has not been detailed. Hence, this review will present an exhaustive summary of the existing biomaterial based strategies to disrupt tumor vascular function for effective cancer treatment, including hydrogel or nanogel-mediated local arterial embolism, thrombosis activator loaded nano-material-mediated vascular occlusion and anti-vascular drugs that block tumor vascular function, which may be beneficial to the design of anti-cancer nanomedicine by targeting the tumor vascular system.
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Affiliation(s)
- Minting Liu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Caisheng Wu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Lingjie Ke
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Zhiguo Li
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
| | - Yun-Long Wu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, 361102, China
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Choi A, Yoon H, Han SJ, Lee JH, Rhyou IH, Kim DS. Rapid harvesting of stem cell sheets by thermoresponsive bulk poly( N-isopropylacrylamide) (PNIPAAm) nanotopography. Biomater Sci 2021; 8:5260-5270. [PMID: 32930245 DOI: 10.1039/d0bm01338b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
To date, cell sheet engineering-based technologies have actualized diverse scaffold-free bio-products to revitalize unintentionally damaged tissues/organs, including cardiomyopathy, corneal defects, and periodontal damage. Although substantial interest is now centered on the practical utilization of these bio-products for patients, the long harvest period of stem cells- or other primary cell-sheets has become a huge hurdle. Here, we dramatically reduce the total harvest period of a cell sheet (from cell layer formation to cell sheet detachment) composed of human bone marrow mesenchymal stem cells (hBMSCs) down to 2 d with the help of bulk thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) substrate nanotopography, which is not achievable via the previous grafting methods using PNIPAAm. We directly replicated an isotropic 400 nm-nanopore-array pattern on a bulk PNIPAAm substrate through UV polymerization of highly concentrated NIPAAm monomers, which was achieved using a remarkably increased Young's modulus of bulk PNIPAAm that was 1500 times higher than conventional PNIPAAm. The rapid harvesting of the hBMSC sheet on the bulk PNIPAAm substrate nanotopography was not only based on the accelerated formation and maturation of the hBMSC layer, but also the easy detachment of the hBMSC sheet induced by the abrupt change in the surface roughness of the substrate below the lower critical solution temperature (LCST) owing to the enlarged surface area of the substrate. Our findings may contribute to reverse presumptions about the limitations regarding the grafting methods for the cell sheet harvest and could broaden the practical utilization of cell sheets for patients in the near future.
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Affiliation(s)
- Andrew Choi
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Korea.
| | - Hyungjun Yoon
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Korea.
| | - Seon Jin Han
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Korea.
| | - Ji-Ho Lee
- Department of Orthopedic Surgery, Pohang Semyeong Christianity Hospital, 351 Posco-daero, Pohang, 37816, Korea
| | - In Hyeok Rhyou
- Department of Orthopedic Surgery, Pohang Semyeong Christianity Hospital, 351 Posco-daero, Pohang, 37816, Korea
| | - Dong Sung Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Korea.
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Rezaei F, Damoogh S, Reis RL, Kundu SC, Mottaghitalab F, Farokhi M. Dual drug delivery system based on pH-sensitive silk fibroin/alginate nanoparticles entrapped in PNIPAM hydrogel for treating severe infected burn wound. Biofabrication 2020; 13:015005. [PMID: 33078712 DOI: 10.1088/1758-5090/abbb82] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Herein, the pH-sensitive vancomycin (VANCO) loaded silk fibroin-sodium alginate nanoparticles (NPs) embedded in poly(N-isopropylacrylamide) (PNIPAM) hydrogel containing epidermal growth factor (EGF) are introduced for treating chronic burn wound infections. The hybrid system was developed to control the release rates of an antibiotic and growth factor for optimal treatment of burn infections. VANCO had a pH responsive release behavior from the nanoparticle (NP) and showed higher release rate in an alkaline pH compared to the neutral pH during 10 d. About 30% of EGF was also released from the hydrogel within 20 d. The released VANCO and EGF preserved their bioactivity more than ∼ 80%. The suitable physico-chemical properties and cellular behaviors of PNIPAM hydrogel supported the proliferation and growth of the fibroblast cells. Furthermore, the higher re-epithelialization with good wound contraction rate, neovascular formation, and expression of transforming growth factor-beta were observed in S. aureus infected rat burn wound by using the hydrogel containing VANCO and EGF compared with untreated wounds and hydrogel alone. The wound infection was also significantly reduced in the groups treated with the hydrogels containing VANCO. Overall, in vitro and in vivo results suggested that developed hybrid system would be a promising construct to treat severe wound infection.
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Affiliation(s)
- Fatemeh Rezaei
- Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran 15875/4413, Iran. These authors contributed equally to this work
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Chimisso V, Aleman Garcia MA, Yorulmaz Avsar S, Dinu IA, Palivan CG. Design of Bio-Conjugated Hydrogels for Regenerative Medicine Applications: From Polymer Scaffold to Biomolecule Choice. Molecules 2020; 25:E4090. [PMID: 32906772 PMCID: PMC7571016 DOI: 10.3390/molecules25184090] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/28/2020] [Accepted: 09/04/2020] [Indexed: 12/26/2022] Open
Abstract
Bio-conjugated hydrogels merge the functionality of a synthetic network with the activity of a biomolecule, becoming thus an interesting class of materials for a variety of biomedical applications. This combination allows the fine tuning of their functionality and activity, whilst retaining biocompatibility, responsivity and displaying tunable chemical and mechanical properties. A complex scenario of molecular factors and conditions have to be taken into account to ensure the correct functionality of the bio-hydrogel as a scaffold or a delivery system, including the polymer backbone and biomolecule choice, polymerization conditions, architecture and biocompatibility. In this review, we present these key factors and conditions that have to match together to ensure the correct functionality of the bio-conjugated hydrogel. We then present recent examples of bio-conjugated hydrogel systems paving the way for regenerative medicine applications.
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Affiliation(s)
| | | | | | | | - Cornelia G. Palivan
- Department of Chemistry, University of Basel, Mattenstrasse 24a, BPR-1096, 4058 Basel, Switzerland; (V.C.); (M.A.A.G.); (S.Y.A.); (I.A.D.)
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9
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Takigawa T, Horinaka JI. Application of a Clapeyron-Type Equation to the Volume Phase Transition of Polymer Gels. Gels 2020; 6:gels6030025. [PMID: 32824049 PMCID: PMC7558151 DOI: 10.3390/gels6030025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 11/16/2022] Open
Abstract
The applicability of the Clapeyron equation to the volume phase transition of cylindrical poly(N-isopropylacrylamide)-based gels under external force is reviewed. Firstly, the equilibrium conditions for the gels under tension are shown, and then we demonstrate that the Clapeyron equation can be applied to the volume phase transition of polymer gels to give the transition entropy or the transition enthalpy. The transition enthalpy at the volume phase transition obtained from the Clapeyron equation is compared with that from the calorimetry. A coefficient of performance, or work efficiency, for a gel actuator driven by the volume phase transition is also defined. How the work efficiency depends on applied force is shown based on a simple mechanical model. It is also shown that the force dependence of transition temperature is closely related to the efficiency curve. Experimental results are compared with the theoretical prediction.
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Stratigaki M, Baumann C, van Breemen LCA, Heuts JPA, Sijbesma RP, Göstl R. Fractography of poly(N-isopropylacrylamide) hydrogel networks crosslinked with mechanofluorophores using confocal laser scanning microscopy. Polym Chem 2020. [DOI: 10.1039/c9py00819e] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Employing mechanofluorophores in polymer fractography to obtain new information on force-induced events when analyzed by confocal laser scanning microscopy.
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Affiliation(s)
- Maria Stratigaki
- DWI – Leibniz Institute for Interactive Materials
- 52056 Aachen
- Germany
| | - Christoph Baumann
- DWI – Leibniz Institute for Interactive Materials
- 52056 Aachen
- Germany
| | - Lambert C. A. van Breemen
- Department of Mechanical Engineering
- Polymer Technology
- Eindhoven University of Technology
- 5600 MB Eindhoven
- The Netherlands
| | - Johan P. A. Heuts
- Laboratory of Supramolecular Polymer Chemistry
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- 5600 MB Eindhoven
- The Netherlands
| | - Rint P. Sijbesma
- Laboratory of Supramolecular Polymer Chemistry
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- 5600 MB Eindhoven
- The Netherlands
| | - Robert Göstl
- DWI – Leibniz Institute for Interactive Materials
- 52056 Aachen
- Germany
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de Lima GG, Elter JK, Chee BS, Magalhães WLE, Devine DM, Nugent MJD, de Sá MJC. A tough and novel dual-response PAA/P(NiPAAM-co-PEGDMA) IPN hydrogels with ceramics by photopolymerization for consolidation of bone fragments following fracture. ACTA ACUST UNITED AC 2019; 14:054101. [PMID: 31282388 DOI: 10.1088/1748-605x/ab2fa3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this work, a novel dual-response hydrogel for enhanced bone repair following multiple fractures was investigated. The conventional treatment of multiple bone fracture consists on removing smaller bone fragments from the body in a surgery, followed by the fixation of the bone using screws and plates. This work proposes an alternative for this treatment via in situ UV-initiated radical polymerization of a novel IPN hydrogel composed of PAA/P(NiPAAM-co-PEGDMA) incorporated with ceramic additives. The influence of different additives on mechanical properties and sensitivity of the polymer, as well as the prepolymer mixture, were investigated in order to analyse the suitability of the composites for bone healing applications. This material exhibited an interpenetrating network, confirmed by FTIR, with ceramics particles dispersed in between the polymer network. These structures presented high strength by tensile tests, sensitivity to pH and temperature and a decrease on Tg values of NiPAAm depending on the amount of PEGDMA and ceramics added; although, the addition of ceramics to these composites did not decrease their stability drastically. Finally, cytotoxicity tests revealed variations on the toxicity, whereas the addition of TCP presented to be non-toxic and that the cell viability increased when ceramics additives were incorporated into the polymeric matrix with an increased reporter activity of NF-κB, associated with aiding fibroblast adhesion. Hence, it was possible to optimise feedstock ratios to increase the applicability of the prepolymer mixture as a potential treatment of multiple fractures.
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Affiliation(s)
- Gabriel Goetten de Lima
- Materials Research Institute, Athlone Institute of Technology, Athlone, Ireland. Universidade Federal do Paraná, Programa de Pós-Graduação em Engenharia e Ciência dos Materiais - PIPE, Curitiba, PR, Brazil
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12
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Zhang N, Zheng S, Pan Z, Liu Z. Phase Transition Effects on Mechanical Properties of NIPA Hydrogel. Polymers (Basel) 2018; 10:E358. [PMID: 30966393 PMCID: PMC6414852 DOI: 10.3390/polym10040358] [Citation(s) in RCA: 11] [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: 03/08/2018] [Revised: 03/08/2018] [Accepted: 03/20/2018] [Indexed: 11/16/2022] Open
Abstract
Due to its excellent temperature sensitivity, the Poly(N-isopropylacrylamide) (NIPA) hydrogel has attracted great interest for a wide variety of applications in tissue engineering and regenerative medicine. NIPA hydrogel undergoes an abrupt volume phase transition at a lower critical solution temperature (LCST) of 30⁻35 °C. However, the mechanical behaviors of NIPA hydrogel induced by phase transition are still not well understood. In this study, phase transition effects on mechanical properties of NIPA hydrogel are quantitatively studied from experimental studies. The mechanical properties of NIPA hydrogel with the LSCT around 35 °C are systemically studied with varying temperatures (31⁻39 °C) under a tensile test. We find that the mechanical properties of NIPA hydrogel are greatly influenced by phase transition during the tension process. The maximum nominal stress and maximum stretch above the LCST are larger than those of below the LCST. The Young's modulus of NIPA hydrogel is around 13 kPa at 31 °C and approximately 28 kPa at 39 °C. A dramatic increase of Young's modulus values is observed as the temperature increases through the phase transition. The samples at a temperature around the LCST are easy to rupture, because of phase coexistent. Additionally, NIPA hydrogel displays toughening behavior under a cyclic load. Furthermore, the toughening characteristic is different between the swollen state and the collapsed state. This might originate from the internal fracture process and redistribution of polymer chains during the tension process.
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Affiliation(s)
- Ni Zhang
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structure, Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Shoujing Zheng
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structure, Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Zhouzhou Pan
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structure, Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Zishun Liu
- International Center for Applied Mechanics, State Key Laboratory for Strength and Vibration of Mechanical Structure, Shaanxi Engineering Research Center of Nondestructive Testing and Structural Integrity Evaluation, Xi'an Jiaotong University, Xi'an 710049, China.
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Haq MA, Su Y, Wang D. Mechanical properties of PNIPAM based hydrogels: A review. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 70:842-855. [PMID: 27770962 DOI: 10.1016/j.msec.2016.09.081] [Citation(s) in RCA: 275] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/13/2016] [Accepted: 09/29/2016] [Indexed: 11/26/2022]
Abstract
Materials which adjust their properties in response to environmental factors such as temperature, pH and ionic strength are rapidly evolving and known as smart materials. Hydrogels formed by smart polymers have various applications. Among the smart polymers, thermoresponsive polymer poly(N-isopropylacrylamide)(PNIPAM) is very important because of its well defined structure and property specially its temperature response is closed to human body and can be finetuned as well. Mechanical properties are critical for the performance of stimuli responsive hydrogels in diverse applications. However, native PNIPAM hydrogels are very fragile and hardly useful for any practical purpose. Intense researches have been done in recent decade to enhance the mechanical features of PNIPAM hydrogel. In this review, several strategies including interpenetrating polymer network (IPN), double network (DN), nanocomposite (NC) and slide ring (SR) hydrogels are discussed in the context of PNIPAM hydrogel.
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Affiliation(s)
- Muhammad Abdul Haq
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; Laboratory of Food Engineering, Department of Food Science & Technology, University of Karachi, Karachi, Pakistan
| | - Yunlan Su
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China.
| | - Dujin Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Engineering Plastics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China
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14
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Puleo G, Zulli F, Piovanelli M, Giordano M, Mazzolai B, Beccai L, Andreozzi L. Mechanical and rheological behavior of pNIPAAM crosslinked macrohydrogel. REACT FUNCT POLYM 2013. [DOI: 10.1016/j.reactfunctpolym.2013.07.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Galperin A, Long TJ, Garty S, Ratner BD. Synthesis and fabrication of a degradable poly(N-isopropyl acrylamide) scaffold for tissue engineering applications. J Biomed Mater Res A 2012; 101:775-86. [PMID: 22961921 DOI: 10.1002/jbm.a.34380] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 07/16/2012] [Accepted: 07/17/2012] [Indexed: 02/02/2023]
Abstract
Biodegradable poly(N-isopropyl acrylamide) (polyNIPAM) hydrogels with controlled molecular weight of the parent polymer and its degradation products were synthesized by atom transfer radical polymerization in the presence of a polycaprolactone-based di-chlorinated macroinitiator and polycaprolactone dimethacrylate. The phase transition temperature, swelling, hydrolytic degradability, and mechanical properties at 25 and 37°C were explored. A cytocompatibility study showed good NIH3T3 cell response over 5 days culture on the surface of the hydrogels, demonstrated by a consistent increase in cell proliferation detected by an Alamar Blue assay. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] results suggested that the hydrogels and their degradation products in the concentration range of 1-25 mg/mL were not cytotoxic to NIH3T3 cells. A sphere-templating technique was utilized to fabricate biodegradable polyNIPAM scaffolds with monodisperse, pore size. Scaffolds with pore diameter of 48 ± 6 μm were loaded with A-10 smooth muscle cells and then warmed to 37°C entrapping cells in pores approximately 40 μm in diameter, a size we have found to be optimal for angiogenesis and biointegration. Due to their degradable nature, tunable molecular weight, highly interconnected morphology, thermally controlled monodisperse pore size, and temperature-induced volume expansion-contraction, the polyNIPAM-based scaffolds developed in this work will be valuable in tissue engineering.
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Affiliation(s)
- Anna Galperin
- University of Washington, Department of Bioengineering, Seattle, Washington 98195, USA
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Kim HN, Kang DH, Kim MS, Jiao A, Kim DH, Suh KY. Patterning methods for polymers in cell and tissue engineering. Ann Biomed Eng 2012; 40:1339-55. [PMID: 22258887 PMCID: PMC5439960 DOI: 10.1007/s10439-012-0510-y] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 01/04/2012] [Indexed: 12/23/2022]
Abstract
Polymers provide a versatile platform for mimicking various aspects of physiological extracellular matrix properties such as chemical composition, rigidity, and topography for use in cell and tissue engineering applications. In this review, we provide a brief overview of patterning methods of various polymers with a particular focus on biocompatibility and processability. The materials highlighted here are widely used polymers including thermally curable polydimethyl siloxane, ultraviolet-curable polyurethane acrylate and polyethylene glycol, thermo-sensitive poly(N-isopropylacrylamide) and thermoplastic and conductive polymers. We also discuss how micro- and nanofabricated polymeric substrates of tunable elastic modulus can be used to engineer cell and tissue structure and function. Such synergistic effect of topography and rigidity of polymers may be able to contribute to constructing more physiologically relevant microenvironment.
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Affiliation(s)
- Hong Nam Kim
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Do-Hyun Kang
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Min Sung Kim
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
| | - Alex Jiao
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Deok-Ho Kim
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Kahp-Yang Suh
- School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-742, Korea
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Hao J, Weiss RA. Viscoelastic and Mechanical Behavior of Hydrophobically Modified Hydrogels. Macromolecules 2011. [DOI: 10.1021/ma202130u] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jinkun Hao
- Department of Polymer Engineering, University of Akron, 250 South Forge Street, Akron, Ohio 44325-0301, United States
| | - R. A. Weiss
- Department of Polymer Engineering, University of Akron, 250 South Forge Street, Akron, Ohio 44325-0301, United States
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Dumitriu RP, Mitchell GR, Vasile C. Rheological and thermal behaviour of poly(N
-isopropylacrylamide)/alginate smart polymeric networks. POLYM INT 2011. [DOI: 10.1002/pi.3093] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nordstrom KN, Verneuil E, Ellenbroek WG, Lubensky TC, Gollub JP, Durian DJ. Centrifugal compression of soft particle packings: theory and experiment. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 82:041403. [PMID: 21230273 DOI: 10.1103/physreve.82.041403] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Indexed: 05/30/2023]
Abstract
An exact method is developed for computing the height of an elastic medium subjected to centrifugal compression, for arbitrary constitutive relation between stress and strain. Example solutions are obtained for power-law media and for cases where the stress diverges at a critical strain--for example as required by packings composed of deformable but incompressible particles. Experimental data are presented for the centrifugal compression of thermo-responsive N-isopropylacrylamide (NIPA) microgel beads in water. For small radial acceleration, the results are consistent with Hertzian elasticity, and are analyzed in terms of the Young elastic modulus of the bead material. For large radial acceleration, the sample compression asymptotes to a value corresponding to a space-filling particle volume fraction of unity. Therefore we conclude that the gel beads are incompressible, and deform without deswelling. In addition, we find that the Young elastic modulus of the particulate gel material scales with cross-link density raised to the power 3.3±0.8, somewhat larger than the Flory expectation.
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Affiliation(s)
- K N Nordstrom
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, USA
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de Moura MR, Ahmad Aouada F, Favaro SL, Radovanovic E, Forti Rubira A, Muniz EC. Release of BSA from porous matrices constituted of alginate–Ca2+ and PNIPAAm-interpenetrated networks. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2009. [DOI: 10.1016/j.msec.2009.05.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Rubira AF, Muniz EC, Guilherme MR, Paulino AT, Tambourgi EB. Morfologia de hidrogéis-ipn termo-sensíveis e ph-responsivos para aplicação como biomaterial na cultura de células. POLIMEROS 2009. [DOI: 10.1590/s0104-14282009000200006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
No presente trabalho, foram sintetizados hidrogéis com ambas as propriedades, termo-sensíveis e pH-responsivos, pela formação de redes de alginato de cálcio (alginato-Ca) dentro de redes de poli(N-Isopropil Acrilamida) (PNIPAAm), resultando em um sistema IPN (sistema de redes poliméricas interpenetradas). Através das análises por microscopia de varredura eletrônica (MEV) e ensaios de intumescimento foi possível observar que os hidrogéis IPN exibiram forte contração quando aquecidos acima da LCST (temperatura critica inferior de solubilização) da PNIPAAm, ou seja, acima de temperaturas de 30-35 ºC. Observou-se ainda que devido à contração do hidrogel, houve uma diminuição significativa nos tamanhos de poros os quais foram observados pelas micrografias. Observou-se também que no intervalo de pH estudado os hidrogéis de IPN sofreram significativa variação da estrutura com a variação desse parâmetro. Tal efeito foi atribuído à presença de grupos químicos carregados com alginato, os quais possuem carga elétrica negativa. Os resultados indicaram que o hidrogel formado por alginato-Ca e PNIPAAm possuíram características especificas após variação de pH e temperatura, e que tais características são derivadas dos compostos individuais envolvidos na síntese. Nesse caso, as propriedades de alginato-Ca e PNIPAAm livres foram preservadas dentro do hidrogel. Tal hidrogel ficou mais resistente à aplicação de uma tensão de compressão. Como conclusão, observou-se que os hidrogéis apresentaram morfologia característica para variações controladas de pH e temperatura, podendo ser eficientemente aplicados como biomaterial na cultura de células.
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Gürdağ G, Öz GM. A novel poly(N
-isopropylacrylamide-co-N
-hydroxymethyl acrylamide) gel: preparation in the absence/presence of a pore-forming agent and characterization. POLYM ADVAN TECHNOL 2008. [DOI: 10.1002/pat.1254] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Liu K, Ovaert TC, Mason JJ. Preparation and mechanical characterization of a PNIPA hydrogel composite. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2008; 19:1815-1821. [PMID: 18040754 DOI: 10.1007/s10856-007-3325-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Accepted: 11/06/2007] [Indexed: 05/25/2023]
Abstract
A poly (N-isopropylacrylamide) (PNIPA) hydrogel was synthesized by free radical polymerization and reinforced with a polyurethane foam to make a hydrogel composite. The temperature dependence of the elastic modulus of the PNIPA hydrogel and the composite due to volume phase transition was found using a uniaxial compression test, and the swelling property was investigated using an equilibrium swelling ratio experiment. The gel composite preserves the ability to undergo the volume phase transition and its elastic modulus has strong temperature dependence. The temperature dependence of the elastic modulus and swelling ratio of the gel composite were compared to the PNIPA hydrogel. Not surprisingly, the modulus and swelling ratio of the composite were less dramatic than in the gel.
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Affiliation(s)
- Kaifeng Liu
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
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Nosaka S, Ishida T, Urayama K, Takigawa T. Steady flow properties of a mixed solvent through a poly(N-isopropylacrylamide) gel. J Memb Sci 2007. [DOI: 10.1016/j.memsci.2007.08.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Guilherme MR, Campese GM, Radovanovic E, Rubira AF, Tambourgi EB, Muniz EC. Thermo-responsive sandwiched-like membranes of IPN-PNIPAAm/PAAm hydrogels. J Memb Sci 2006. [DOI: 10.1016/j.memsci.2005.09.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Porous alginate-Ca2+ hydrogels interpenetrated with PNIPAAm networks: Interrelationship between compressive stress and pore morphology. Eur Polym J 2005. [DOI: 10.1016/j.eurpolymj.2005.06.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Kaneko T, Asoh TA, Akashi M. Ultrarapid Molecular Release from Poly(N-isopropylacrylamide) Hydrogels Perforated Using Silica Nanoparticle Networks. MACROMOL CHEM PHYS 2005. [DOI: 10.1002/macp.200400405] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Takigawa T, Nosaka S, Takakura Y, Urayama K. Dynamic Swelling Properties of a Poly(N-isopropylacrylamide) Gel Measured by a Magnetic Force-Driven Rheometer. Polym J 2003. [DOI: 10.1295/polymj.35.819] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Xia X, Yih J, D'Souza NA, Hu Z. Swelling and mechanical behavior of poly(N-isopropylacrylamide)/Na-montmorillonite layered silicates composite gels. POLYMER 2003. [DOI: 10.1016/s0032-3861(03)00228-3] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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31
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Serizawa T, Wakita K, Kaneko T, Akashi M. Thermoresponsive properties of porous poly(N-isopropylacrylamide) hydrogels prepared in the presence of nanosized silica particles and subsequent acid treatment. ACTA ACUST UNITED AC 2002. [DOI: 10.1002/pola.10482] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Matzelle TR, Ivanov DA, Landwehr D, Heinrich LA, Herkt-Bruns C, Reichelt R, Kruse N. Micromechanical Properties of “Smart” Gels: Studies by Scanning Force and Scanning Electron Microscopy of PNIPAAm. J Phys Chem B 2002. [DOI: 10.1021/jp0128426] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- T. R. Matzelle
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - D. A. Ivanov
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - D. Landwehr
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - L. A. Heinrich
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - Ch. Herkt-Bruns
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - R. Reichelt
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
| | - N. Kruse
- Chimie Physique des Matériaux, CP 243, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, Laboratoire de Physique des Polymères, CP 223, Université Libre de Bruxelles, B-1050 Bruxelles, Belgium, DEGUSSA AG, CREAVIS Technologies and Innovation, D-45746 Marl, Germany, and Institut für Medizinische Physik und Biophysik, Westfälische Wilhelms-Universität, D-48149 Münster, Germany
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