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Grachev V, Deschaume O, Lang PR, Lettinga MP, Bartic C, Thielemans W. Dimensions of Cellulose Nanocrystals from Cotton and Bacterial Cellulose: Comparison of Microscopy and Scattering Techniques. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:455. [PMID: 38470785 DOI: 10.3390/nano14050455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 02/25/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024]
Abstract
Different microscopy and scattering methods used in the literature to determine the dimensions of cellulose nanocrystals derived from cotton and bacterial cellulose were compared to investigate potential bias and discrepancies. Atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), depolarized dynamic light scattering (DDLS), and static light scattering (SLS) were compared. The lengths, widths, and heights of the particles and their respective distributions were determined by AFM. In agreement with previous work, the CNCs were found to have a ribbon-like shape, regardless of the source of cellulose or the surface functional groups. Tip broadening and agglomeration of the particles during deposition cause AFM-derived lateral dimensions to be systematically larger those obtained from SAXS measurements. The radius of gyration determined by SLS showed a good correlation with the dimensions obtained by AFM. The hydrodynamic lateral dimensions determined by DDLS were found to have the same magnitude as either the width or height obtained from the other techniques; however, the precision of DDLS was limited due to the mismatch between the cylindrical model and the actual shape of the CNCs, and to constraints in the fitting procedure. Therefore, the combination of AFM and SAXS, or microscopy and small-angle scattering, is recommended for the most accurate determination of CNC dimensions.
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Affiliation(s)
- Vladimir Grachev
- Sustainable Materials Lab, Department of Chemical Engineering, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium
| | - Olivier Deschaume
- Laboratory for Soft Matter Physics and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D Box 2416, 3001 Leuven, Belgium
| | - Peter R Lang
- Institute for Biomacromolecular Systems and Processes Group (IBI-4), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Minne Paul Lettinga
- Laboratory for Soft Matter Physics and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D Box 2416, 3001 Leuven, Belgium
- Institute for Biomacromolecular Systems and Processes Group (IBI-4), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Carmen Bartic
- Laboratory for Soft Matter Physics and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D Box 2416, 3001 Leuven, Belgium
| | - Wim Thielemans
- Sustainable Materials Lab, Department of Chemical Engineering, KU Leuven, Campus Kulak Kortrijk, Etienne Sabbelaan 53, 8500 Kortrijk, Belgium
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2
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Babaei-Ghazvini A, Vafakish B, Patel R, Falua KJ, Dunlop MJ, Acharya B. Cellulose nanocrystals in the development of biodegradable materials: A review on CNC resources, modification, and their hybridization. Int J Biol Macromol 2024; 258:128834. [PMID: 38128804 DOI: 10.1016/j.ijbiomac.2023.128834] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 12/03/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023]
Abstract
The escalating demand for sustainable materials has propelled cellulose into the spotlight as a promising alternative to petroleum-based products. As the most abundant organic polymer on Earth, cellulose is ubiquitous, found in plants, bacteria, and even a unique marine animal-the tunicate. Cellulose polymers naturally give rise to microscale semi-crystalline fibers and nanoscale crystalline regions known as cellulose nanocrystals (CNCs). Exhibiting rod-like structures with widths spanning 3 to 50 nm and lengths ranging from 50 nm to several microns, CNC characteristics vary based on the cellulose source. The degree of crystallinity, crucial for CNC properties, fluctuates between 49 and 95 % depending on the source and synthesis method. CNCs, with their exceptional properties such as high aspect ratio, relatively low density (≈1.6 g cm-3), high axial elastic modulus (≈150 GPa), significant tensile strength, and birefringence, emerge as ideal candidates for biodegradable fillers in nanocomposites and functional materials. The percolation threshold, a mathematical concept defining long-range connectivity between filler and polymer, governs the effectiveness of reinforcement in nanocomposites. This threshold is intricately influenced by the aspect ratio and molecular interaction strength, impacting CNC performance in polymeric and pure nanocomposite materials. This comprehensive review explores diverse aspects of CNCs, encompassing their derivation from various sources, methods of modification (both physical and chemical), and hybridization with heterogeneous fillers. Special attention is devoted to the hybridization of CNCs derived from tunicates (TCNC) with those from wood (WCNC), leveraging the distinct advantages of each. The overarching objective is to demonstrate how this hybridization strategy mitigates the limitations of WCNC in composite materials, offering improved interaction and enhanced percolation. This, in turn, is anticipated to elevate the reinforcing effects and pave the way for the development of nanocomposites with tunable viscoelastic, physicochemical, and mechanical properties.
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Affiliation(s)
- Amin Babaei-Ghazvini
- Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada.
| | - Bahareh Vafakish
- Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada.
| | - Ravi Patel
- Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada.
| | - Kehinde James Falua
- Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada.
| | - Matthew J Dunlop
- Tunistrong Technologies Incorporated, 7207 Route 11, Wellington, Charlottetown, PE C0B 20E, Canada.
| | - Bishnu Acharya
- Department of Chemical and Biological Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada.
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3
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Frka-Petesic B, Parton TG, Honorato-Rios C, Narkevicius A, Ballu K, Shen Q, Lu Z, Ogawa Y, Haataja JS, Droguet BE, Parker RM, Vignolini S. Structural Color from Cellulose Nanocrystals or Chitin Nanocrystals: Self-Assembly, Optics, and Applications. Chem Rev 2023; 123:12595-12756. [PMID: 38011110 PMCID: PMC10729353 DOI: 10.1021/acs.chemrev.2c00836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Indexed: 11/29/2023]
Abstract
Widespread concerns over the impact of human activity on the environment have resulted in a desire to replace artificial functional materials with naturally derived alternatives. As such, polysaccharides are drawing increasing attention due to offering a renewable, biodegradable, and biocompatible feedstock for functional nanomaterials. In particular, nanocrystals of cellulose and chitin have emerged as versatile and sustainable building blocks for diverse applications, ranging from mechanical reinforcement to structural coloration. Much of this interest arises from the tendency of these colloidally stable nanoparticles to self-organize in water into a lyotropic cholesteric liquid crystal, which can be readily manipulated in terms of its periodicity, structure, and geometry. Importantly, this helicoidal ordering can be retained into the solid-state, offering an accessible route to complex nanostructured films, coatings, and particles. In this review, the process of forming iridescent, structurally colored films from suspensions of cellulose nanocrystals (CNCs) is summarized and the mechanisms underlying the chemical and physical phenomena at each stage in the process explored. Analogy is then drawn with chitin nanocrystals (ChNCs), allowing for key differences to be critically assessed and strategies toward structural coloration to be presented. Importantly, the progress toward translating this technology from academia to industry is summarized, with unresolved scientific and technical questions put forward as challenges to the community.
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Affiliation(s)
- Bruno Frka-Petesic
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
- International
Institute for Sustainability with Knotted Chiral Meta Matter (WPI-SKCM), Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Thomas G. Parton
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Camila Honorato-Rios
- Department
of Sustainable and Bio-inspired Materials, Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam, Germany
| | - Aurimas Narkevicius
- B
CUBE − Center for Molecular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Kevin Ballu
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Qingchen Shen
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Zihao Lu
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Yu Ogawa
- CERMAV-CNRS,
CS40700, 38041 Grenoble cedex 9, France
| | - Johannes S. Haataja
- Department
of Applied Physics, Aalto University School
of Science, P.O. Box
15100, Aalto, Espoo FI-00076, Finland
| | - Benjamin E. Droguet
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Richard M. Parker
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Silvia Vignolini
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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4
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Soullard L, Pradalié F, Labat B, Lancelon-Pin C, Nonglaton G, Rolere S, Texier I, Jean B. Methacrylated Cellulose Nanocrystals as Fillers for the Development of Photo-Cross-Linkable Cytocompatible Biosourced Formulations Targeting 3D Printing. Biomacromolecules 2023; 24:6009-6024. [PMID: 38073466 DOI: 10.1021/acs.biomac.3c01090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Cellulose nanocrystals (CNCs) from cotton were functionalized in aqueous medium using methacrylic anhydride (MA) to produce methacrylated cellulose nanocrystals (mCNCs) with a degree of methacrylation (DM) up to 12.6 ± 0.50%. Dispersible as-prepared CNCs and mCNCs were then considered as reinforcing fillers for aqueous 3D-printable formulations based on methacrylated carboxymethylcellulose (mCMC). The rheological properties of such photo-cross-linkable aqueous formulations containing nonmodified CNCs or mCNCs at 0.2 or 0.5 wt% in 2 wt% mCMC were fully investigated. The influence of the presence of nanoparticles on the UV-curing kinetics and dimensions of the photo-cross-linked hydrogels was probed and 13C CP-MAS NMR spectroscopy was used to determine the maximum conversion ratio of methacrylates as well as the optimized time required for UV postcuring. The viscoelasticity of cross-linked hydrogels and swollen hydrogels was also studied. The addition of 0.5 wt% mCNC with a DM of 0.83 ± 0.040% to the formulation yielded faster cross-linking kinetics, better resolution, more robust cross-linked hydrogels, and more stable swollen hydrogels than pure mCMC materials. Additionally, the produced cryogels showed no cytotoxicity toward L929 fibroblasts. This biobased formulation could thus be considered for the 3D printing of hydrogels dedicated to biomedical purposes using vat polymerization techniques, such as stereolithography or digital light processing.
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Affiliation(s)
- Lénaïc Soullard
- Univ. Grenoble Alpes, CEA, LITEN, DTNM, Grenoble 38054, France
- Univ. Grenoble Alpes, CEA, LETI, DTBS, Grenoble 38054, France
- Univ. Grenoble Alpes, CNRS, CERMAV, Saint-Martin-d'Hères 38041, France
| | - Flavie Pradalié
- Univ. Grenoble Alpes, CNRS, CERMAV, Saint-Martin-d'Hères 38041, France
| | - Béatrice Labat
- Univ. Rouen Normandie, INSA Rouen Normandie, CNRS, PBS, Evreux 27000, France
| | | | | | | | - Isabelle Texier
- Univ. Grenoble Alpes, CEA, LETI, DTBS, Grenoble 38054, France
| | - Bruno Jean
- Univ. Grenoble Alpes, CNRS, CERMAV, Saint-Martin-d'Hères 38041, France
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5
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Attia D, Mendelson O, Levi-Kalisman Y, Bitton R, Yerushalmi-Rozen R. Enantioselective disruption of cellulose nanocrystal self-assembly into chiral nematic phases in D-alanine solutions. NANOSCALE 2023; 15:16890-16895. [PMID: 37847510 DOI: 10.1039/d3nr03077f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
The chiral environment of enantiomerically pure D-alanine solutions is observed to disrupt and modify the entropy-driven assembly of cellulose nanocrystals (CNCs) into a chiral nematic mesophase. The effect is specific to D-alanine and cannot be attributed to the adsorption of alanine molecules (neither D- nor L-alanine) onto the CNC particles.
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Affiliation(s)
- David Attia
- Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
| | - Orit Mendelson
- Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- Nuclear Research Center-Negev, Department of Chemistry, Beer-Sheva 84190, Israel
| | - Yael Levi-Kalisman
- The Center for Nanoscience and Nanotechnology, and the Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Ronit Bitton
- Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- The Ilse Katz Institute for Nanoscience and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Rachel Yerushalmi-Rozen
- Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
- The Ilse Katz Institute for Nanoscience and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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Solhi L, Guccini V, Heise K, Solala I, Niinivaara E, Xu W, Mihhels K, Kröger M, Meng Z, Wohlert J, Tao H, Cranston ED, Kontturi E. Understanding Nanocellulose-Water Interactions: Turning a Detriment into an Asset. Chem Rev 2023; 123:1925-2015. [PMID: 36724185 PMCID: PMC9999435 DOI: 10.1021/acs.chemrev.2c00611] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Modern technology has enabled the isolation of nanocellulose from plant-based fibers, and the current trend focuses on utilizing nanocellulose in a broad range of sustainable materials applications. Water is generally seen as a detrimental component when in contact with nanocellulose-based materials, just like it is harmful for traditional cellulosic materials such as paper or cardboard. However, water is an integral component in plants, and many applications of nanocellulose already accept the presence of water or make use of it. This review gives a comprehensive account of nanocellulose-water interactions and their repercussions in all key areas of contemporary research: fundamental physical chemistry, chemical modification of nanocellulose, materials applications, and analytical methods to map the water interactions and the effect of water on a nanocellulose matrix.
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Affiliation(s)
- Laleh Solhi
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Valentina Guccini
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Katja Heise
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Iina Solala
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Elina Niinivaara
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland.,Department of Wood Science, University of British Columbia, Vancouver, British ColumbiaV6T 1Z4, Canada
| | - Wenyang Xu
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland.,Laboratory of Natural Materials Technology, Åbo Akademi University, TurkuFI-20500, Finland
| | - Karl Mihhels
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Marcel Kröger
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Zhuojun Meng
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland.,Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou325001, China
| | - Jakob Wohlert
- Wallenberg Wood Science Centre (WWSC), Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 10044Stockholm, Sweden
| | - Han Tao
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
| | - Emily D Cranston
- Department of Wood Science, University of British Columbia, Vancouver, British ColumbiaV6T 1Z4, Canada.,Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, British ColumbiaV6T 1Z3, Canada
| | - Eero Kontturi
- Department of Bioproducts and Biosystems, Aalto University, EspooFI-00076, Finland
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7
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Babaei-Ghazvini A, Acharya B. Influence of cellulose nanocrystal aspect ratio on shear force aligned films: Physical and mechanical properties. CARBOHYDRATE POLYMER TECHNOLOGIES AND APPLICATIONS 2022. [DOI: 10.1016/j.carpta.2022.100217] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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8
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Ribeiro LS, Sala RL, de Jesus LAO, Cruz SA, Camargo ER. Analyzing the Effects of Silica Nanospheres on the Sol-Gel Transition Profile of Thermosensitive Hydrogels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:7373-7379. [PMID: 34101480 DOI: 10.1021/acs.langmuir.1c00723] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The insertion of nanoparticles into smart hydrogels can diversify their functionalities by a synergistic combination of the components properties within the hydrogels. While these hybrid systems are attractive to the biomaterials field, careful design and control of their properties are required since the new interactions between the polymer and the nanoparticles can result in changes or the loss of hydrogels stimuli response. In order to understand the physicochemical aspects of the thermoresponsive systems, nanocomposites of poly(N-vinylcaprolactam) (PNVCL) and silica nanoparticles with different sizes and concentrations were synthesized. The UV-vis and DLS techniques showed that the PNVCL has a sharp phase transition at 34 °C, while the nanocomposites have a diffuse transition. The nanocomposites showed an initial coil-globule transition before the phase transition takes place. This was identified by the evolution of the hydrodynamic diameter of the nanocomposite globules before the cloud point temperature (Tcp), which remained constant for PNVCL. This new transition profile can be described by two stages in which microscopic volume transitions occur first, followed by the macroscopic transition that forms the hydrogel. These results show that the proposed nanocomposites can be designed to have tunable stimuli response to smaller temperature variations with the formation of intermediate globule states.
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Affiliation(s)
- Lucas S Ribeiro
- Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luis km 235, CP 676, São Carlos, São Paulo 13565-905, Brazil
| | - Renata L Sala
- Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luis km 235, CP 676, São Carlos, São Paulo 13565-905, Brazil
| | - Leticia A O de Jesus
- Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luis km 235, CP 676, São Carlos, São Paulo 13565-905, Brazil
| | - Sandra A Cruz
- Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luis km 235, CP 676, São Carlos, São Paulo 13565-905, Brazil
| | - Emerson R Camargo
- Department of Chemistry, Federal University of São Carlos (UFSCar), Rod. Washington Luis km 235, CP 676, São Carlos, São Paulo 13565-905, Brazil
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9
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Lin F, Pignon F, Putaux JL, Jean B. Temperature-triggered formation of a cellulose II nanocrystal network through regioselective derivatization. NANOSCALE 2021; 13:6447-6460. [PMID: 33885525 DOI: 10.1039/d0nr08597a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The two ends of rodlike cellulose II nanocrystals (CNC-II) were regioselectively functionalized either with gold nanoparticles or thermosensitive polymer chains. In the first case, after the introduction of sulfur atoms at both ends of the rods, CNC-II were labelled using a method based on the in situ nucleation and growth of gold nanoparticles (AuNPs) from soluble derivatives. Transmission electron microscopy (TEM) images showed that such a method resulted in the grafting of one monodisperse AuNP at each extremity of the CNC-II, i.e. to the formation of hybrid dumbbell-shaped objects. No AuNP was detected on the lateral surfaces of the CNC-II and almost all observed CNC-II exhibited this dual labeling. This result confirmed with a good statistics when compared to previous works the possibility to derivatize only the two ends of the CNC-II, thanks to the antiparallel arrangement of cellulose chains in these nanoparticles. In the second case, the localized grafting of temperature-sensitive macromolecules onto the ends of the CNC-II was performed using an oxidation reaction followed by a peptide coupling. This end-specific grafting of thermosensitive chains onto CNC-II enhanced their colloidal stability when the temperature was below the lower critical solution temperature (LCST) of the polymer. Above the LCST, the TEM images revealed the formation of a network extending to tens of microns resulting from end-to-end associations of the derivatized rods through attractive interactions between collapsed polymer chains. Rheology experiments further evidenced a temperature-induced sol-gel transition from a liquid-like (sol) behavior below the LCST to solid-like (gel) behavior above the LCST, in agreement with a change from purely repulsive interactions to interconnections via the hydrophobic collapsed chains. Importantly, all results concurred with a full reversibility of the phenomena upon cooling and reproducibility when samples were subjected to temperature cycles around the LCST. This work reveals that the dual site-specific derivatization of CNC-II can provide symmetric hybrid particles with innovative assembling and macroscopic properties that cannot be obtained through homogeneous chemical modifications.
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Affiliation(s)
- Fangbo Lin
- Univ. Grenoble Alpes, CNRS, CERMAV, F-38000 Grenoble, France.
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10
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Lin F, Putaux JL, Jean B. RETRACTED: Optimized reducing-end labeling of cellulose nanocrystals: Implication for the structure of microfibril bundles in plant cell walls. Carbohydr Polym 2021; 257:117618. [PMID: 33541646 DOI: 10.1016/j.carbpol.2021.117618] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/01/2021] [Accepted: 01/03/2021] [Indexed: 12/12/2022]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the senior authors of the article; Jean-Luc Putaux and Bruno Jean. There are serious concerns about the reliability of the data presented in this article, which critically affects the main conclusions. Namely, TEM Figs. 3, 6 and 7 show signs of manipulation, such as the presence of repeated fragments and the use of the clone stamp tool applied with some image editing software. The first author of the paper, Fangbo Lin, was contacted regarding this matter but did not respond. The two above mentioned authors apologize for any inconvenience to readers.
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Affiliation(s)
- Fangbo Lin
- Univ. Grenoble Alpes, CNRS, CERMAV, F-38000, Grenoble, France
| | - Jean-Luc Putaux
- Univ. Grenoble Alpes, CNRS, CERMAV, F-38000, Grenoble, France
| | - Bruno Jean
- Univ. Grenoble Alpes, CNRS, CERMAV, F-38000, Grenoble, France.
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