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Datta D, Bandi SP, Colaco V, Dhas N, Saha SS, Hussain SZ, Singh S. Cellulose-Based Nanofibers Infused with Biotherapeutics for Enhanced Wound-Healing Applications. ACS POLYMERS AU 2025; 5:80-104. [PMID: 40226346 PMCID: PMC11986729 DOI: 10.1021/acspolymersau.4c00092] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2024] [Revised: 02/02/2025] [Accepted: 02/03/2025] [Indexed: 04/15/2025]
Abstract
Nanofibers fabricated from various materials such as polymers, carbon, and semiconductors have been widely used for wound healing and tissue engineering applications due to their excellent nontoxic, biocompatible, and biodegradable properties. Nanofibers with a diameter in the nanometer range possess a larger surface area per unit mass permitting easier addition of surface functionalities and release of biotherapeutics incorporated compared with conventional polymeric microfibers. Henceforth, nanofibers are a choice for fabricating scaffolds for the management of wound healing. Nanofibrous scaffolds have emerged as a promising method for fabricating wound dressings since they mimic the fibrous dermal extracellular matrix milieu that offers structural support for wound healing and functional signals for guiding tissue regeneration. Cellulose-based nanofibers have gained significant attention among researchers in the fabrication of on-site biodegradable scaffolds fortified with biotherapeutics in the management of wound healing. Cellulose is a linear, stereoregular insoluble polymer built from repeated units of d-glucopyranose linked with 1,4-β glycoside bonds with a complex and multilevel supramolecular architecture. Cellulose is a choice and has been used by various researchers due to its solubility in many solvents and its capacity for self-assembly into nanofibers, facilitating the mimicry of the natural extracellular matrix fibrous architecture and promoting substantial water retention. It is also abundant and demonstrates low immunogenicity in humans due to its nonanimal origins. To this end, cellulose-based nanofibers have been studied for protein delivery, antibacterial activity, and biosensor applications, among others. Taken together, this review delves into an update on cellulose-based nanofibers fused with bioactive compounds that have not been explored considerably in the past few years.
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Affiliation(s)
- Deepanjan Datta
- Department
of Pharmaceutics, Manipal College of Pharmaceutical
Sciences, Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India
| | - Sony Priyanka Bandi
- Department
of Pharmacy, Birla Institute of Technology
and Science (BITS) Pilani, Hyderabad Campus, Hyderabad, Telangana State 500078, India
| | - Viola Colaco
- Department
of Pharmaceutics, Manipal College of Pharmaceutical
Sciences, Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India
| | - Namdev Dhas
- Department
of Pharmaceutics, Manipal College of Pharmaceutical
Sciences, Manipal Academy of Higher Education, Manipal, Karnataka State 576104, India
| | - Suprio Shantanu Saha
- Department
of Textile Engineering, Khulna University
of Engineering and Technology, Khulna-9203, Khulna, Bangladesh
| | - Syed Zubair Hussain
- Department
of Textile Engineering, Khulna University
of Engineering and Technology, Khulna-9203, Khulna, Bangladesh
| | - Sudarshan Singh
- Faculty
of Pharmacy, Chiang Mai University, Chiang Mai 50200, Thailand
- Office
of Research Administrations, Chiang Mai
University, Chiang Mai 50200, Thailand
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2
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Tian J, Motezakker AR, Wang R, Bae AJ, Fluerasu A, Zhu H, Hsiao BS, Rosén T. Probing the Self-Assembly dynamics of cellulose nanocrystals by X-ray photon correlation spectroscopy. J Colloid Interface Sci 2025; 683:1077-1086. [PMID: 39778489 DOI: 10.1016/j.jcis.2024.12.234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 10/29/2024] [Accepted: 12/29/2024] [Indexed: 01/11/2025]
Abstract
HYPOTHESIS Charge-stabilized colloidal cellulose nanocrystals (CNCs) can self-assemble into higher-ordered chiral nematic structures by varying the volume fraction. The assembly process exhibits distinct dynamics during the isotropic to liquid crystal phase transition, which can be elucidated using X-ray photon correlation spectroscopy (XPCS). EXPERIMENTS Anionic CNCs were dispersed in propylene glycol (PG) and water spanning a range of volume fractions, encompassing several phase transitions. Coupled with traditional characterization techniques, XPCS was conducted to monitor the dynamic evolution of the different phases. Additionally, simulated XPCS results were obtained using colloidal rods and compared with the experimental data, offering additional insights into the dynamic behavior of the system. FINDINGS The results indicate that the particle dynamics of CNCs undergo a stepped decay in three stages during the self-assembly process in PG, coinciding with the observed phases. The phase transitions are associated with a total drop of Brownian diffusion rates by four orders of magnitude, a decrease of more than a thousand times slower than expected in an ideal system of repulsive Brownian rods. Given the similarity in the phase behaviors in CNCs dispersed in PG and in water, we hypothesize that these dynamic behaviors can be extrapolated to other polar solvent environments. Importantly, these findings represent the direct measurement of CNC dynamics using XPCS, underscoring the feasibility of directly assessing the dynamic behavior of other rod-like colloidal suspensions.
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Affiliation(s)
- Jiajun Tian
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, United States
| | - Ahmad Reza Motezakker
- Department of Mechanics, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Wallenberg Wood Science Center, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Ruifu Wang
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, United States
| | - Andrew J Bae
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, United States
| | - Andrei Fluerasu
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973-5000, United States
| | - Hengwei Zhu
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, United States
| | - Benjamin S Hsiao
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794-3400, United States.
| | - Tomas Rosén
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
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3
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Wang R, He H, Tian J, Chodankar S, Hsiao BS, Rosén T. Solvent-Dependent Dynamics of Cellulose Nanocrystals in Process-Relevant Flow Fields. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:13319-13329. [PMID: 38859701 PMCID: PMC11210288 DOI: 10.1021/acs.langmuir.4c01846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/01/2024] [Accepted: 06/03/2024] [Indexed: 06/12/2024]
Abstract
Flow-assisted alignment of anisotropic nanoparticles is a promising route for the bottom-up assembly of advanced materials with tunable properties. While aligning processes could be optimized by controlling factors such as solvent viscosity, flow deformation, and the structure of the particles themselves, it is necessary to understand the relationship between these factors and their effect on the final orientation. In this study, we investigated the flow of surface-charged cellulose nanocrystals (CNCs) with the shape of a rigid rod dispersed in water and propylene glycol (PG) in an isotropic tactoid state. In situ scanning small-angle X-ray scattering (SAXS) and rheo-optical flow-stop experiments were used to quantify the dynamics, orientation, and structure of the assigned system at the nanometer scale. The effects of both shear and extensional flow fields were revealed in a single experiment by using a flow-focusing channel geometry, which was used as a model flow for nanomaterial assembly. Due to the higher solvent viscosity, CNCs in PG showed much slower Brownian dynamics than CNCs in water and thus could be aligned at lower deformation rates. Moreover, CNCs in PG also formed a characteristic tactoid structure but with less ordering than CNCs in water owing to weaker electrostatic interactions. The results indicate that CNCs in water stay assembled in the mesoscale structure at moderate deformation rates but are broken up at higher flow rates, enhancing rotary diffusion and leading to lower overall alignment. Albeit being a study of cellulose nanoparticles, the fundamental interplay between imposed flow fields, Brownian motion, and electrostatic interactions likely apply to many other anisotropic colloidal systems.
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Affiliation(s)
- Ruifu Wang
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United
States
| | - HongRui He
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United
States
| | - Jiajun Tian
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United
States
| | - Shirish Chodankar
- National
Synchrotron Light Source II, Brookhaven
National Laboratory, Upton, New York 11793-5000, United States
| | - Benjamin S. Hsiao
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United
States
| | - Tomas Rosén
- Department
of Fiber and Polymer Technology and Wallenberg Wood Science Center, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
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4
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Rosén T, He H, Wang R, Gordeyeva K, Motezakker AR, Fluerasu A, Söderberg LD, Hsiao BS. Exploring nanofibrous networks with x-ray photon correlation spectroscopy through a digital twin. Phys Rev E 2023; 108:014607. [PMID: 37583188 DOI: 10.1103/physreve.108.014607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 06/27/2023] [Indexed: 08/17/2023]
Abstract
We demonstrate a framework of interpreting data from x-ray photon correlation spectroscopy experiments with the aid of numerical simulations to describe nanoscale dynamics in soft matter. This is exemplified with the transport of passive tracer gold nanoparticles in networks of charge-stabilized cellulose nanofibers. The main structure of dynamic modes in reciprocal space could be replicated with a simulated system of confined Brownian motion, a digital twin, allowing for a direct measurement of important effective material properties describing the local environment of the tracers.
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Affiliation(s)
- Tomas Rosén
- Department of Fibre and Polymer Technology, Royal Institute of Technology, 100 44 Stockholm, Sweden
- Wallenberg Wood Science Center, Royal Institute of Technology, 100 44 Stockholm, Sweden
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, USA
| | - HongRui He
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, USA
| | - Ruifu Wang
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, USA
| | - Korneliya Gordeyeva
- Department of Fibre and Polymer Technology, Royal Institute of Technology, 100 44 Stockholm, Sweden
- Wallenberg Wood Science Center, Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Ahmad Reza Motezakker
- Wallenberg Wood Science Center, Royal Institute of Technology, 100 44 Stockholm, Sweden
- Department of Mechanics, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Andrei Fluerasu
- National Synchrotron Light Source II, Brookhaven National Lab, Upton, New York 11793, USA
| | - L Daniel Söderberg
- Department of Fibre and Polymer Technology, Royal Institute of Technology, 100 44 Stockholm, Sweden
- Wallenberg Wood Science Center, Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Benjamin S Hsiao
- Department of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, USA
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5
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Rashad A, Grøndahl M, Heggset EB, Mustafa K, Syverud K. Responses of Rat Mesenchymal Stromal Cells to Nanocellulose with Different Functional Groups. ACS APPLIED BIO MATERIALS 2023; 6:987-998. [PMID: 36763504 PMCID: PMC10031564 DOI: 10.1021/acsabm.2c00794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Cellulose nanofibrils (CNFs) are multiscale hydrophilic biocompatible polysaccharide materials derived from wood and plants. TEMPO-mediated oxidation of CNFs (TO-CNF) turns some of the primary hydroxyl groups to carboxylate and aldehyde groups. Unlike carboxylic functional groups, there is little or no information about the biological role of the aldehyde groups on the surface of wood-based CNFs. In this work, we replaced the aldehyde groups in the TO-CNF samples with carboxyl groups by another oxidation treatment (TO-O-CNF) or with primary alcohols with terminal hydroxyl groups by a reduction reaction (TO-R-CNF). Rat mesenchymal stem/stromal cells (MSCs) derived from bone marrow were seeded on polystyrene tissue culture plates (TCP) coated with CNFs with and without aldehyde groups. TCP and TCP coated with bacterial nanocellulose (BNC) were used as control groups. Protein adsorption measurements demonstrated that more proteins were adsorbed from cell culture media on all CNF surfaces compared to BNC. Live/dead and lactate dehydrogenase assays confirmed that all nanocellulose biomaterials supported excellent cell viability. Interestingly, TO-R-CNF samples, which have no aldehyde groups, showed better cell spreading than BNC and comparable results to TCP. Unlike TO-O-CNF surfaces, which have no aldehyde groups either, TO-R-CNF stimulated cells, in osteogenic medium, to have higher alkaline phosphatase activity and to form more biomineralization than TCP and TO-CNF groups. These findings indicate that the presence of aldehyde groups (280 ± 14 μmol/g) on the surface of TEMPO-oxidized CNFs might have little or no effect on attachment, proliferation, and osteogenic differentiation of MSCs.
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Affiliation(s)
- Ahmad Rashad
- Center of Translational Oral Research (TOR), Department of Clinical Dentistry, University of Bergen, Bergen 5009, Norway
| | - Martha Grøndahl
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology, Trondheim 7491, Norway
| | | | - Kamal Mustafa
- Center of Translational Oral Research (TOR), Department of Clinical Dentistry, University of Bergen, Bergen 5009, Norway
| | - Kristin Syverud
- RISE PFI, Trondheim 7491, Norway
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway
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6
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Singh M, Joshi G, Qiang H, Okajima MK, Kaneko T. Facile Design of Antibacterial Sheets of Sacran and Nanocellulose. CARBOHYDRATE POLYMER TECHNOLOGIES AND APPLICATIONS 2023. [DOI: 10.1016/j.carpta.2023.100280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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7
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Wang R, He H, Sharma PR, Tian J, Söderberg LD, Rosén T, Hsiao BS. Unexpected Gelation Behavior of Cellulose Nanofibers Dispersed in Glycols. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ruifu Wang
- Department of Chemistry, Stony Brook University, Stony Brook, New York11794-3400, United States
| | - Hongrui He
- Department of Chemistry, Stony Brook University, Stony Brook, New York11794-3400, United States
| | - Priyanka R. Sharma
- Department of Chemistry, Stony Brook University, Stony Brook, New York11794-3400, United States
| | - Jiajun Tian
- Department of Chemistry, Stony Brook University, Stony Brook, New York11794-3400, United States
| | - L. Daniel Söderberg
- Fiber and Polymer Technology Department, KTH Royal Institute of Technology, StockholmS-100 44, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, StockholmS-100 44, Sweden
| | - Tomas Rosén
- Fiber and Polymer Technology Department, KTH Royal Institute of Technology, StockholmS-100 44, Sweden
- Wallenberg Wood Science Center, KTH Royal Institute of Technology, StockholmS-100 44, Sweden
| | - Benjamin S. Hsiao
- Department of Chemistry, Stony Brook University, Stony Brook, New York11794-3400, United States
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8
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Tardy BL, Mattos BD, Otoni CG, Beaumont M, Majoinen J, Kämäräinen T, Rojas OJ. Deconstruction and Reassembly of Renewable Polymers and Biocolloids into Next Generation Structured Materials. Chem Rev 2021; 121:14088-14188. [PMID: 34415732 PMCID: PMC8630709 DOI: 10.1021/acs.chemrev.0c01333] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Indexed: 12/12/2022]
Abstract
This review considers the most recent developments in supramolecular and supraparticle structures obtained from natural, renewable biopolymers as well as their disassembly and reassembly into engineered materials. We introduce the main interactions that control bottom-up synthesis and top-down design at different length scales, highlighting the promise of natural biopolymers and associated building blocks. The latter have become main actors in the recent surge of the scientific and patent literature related to the subject. Such developments make prominent use of multicomponent and hierarchical polymeric assemblies and structures that contain polysaccharides (cellulose, chitin, and others), polyphenols (lignins, tannins), and proteins (soy, whey, silk, and other proteins). We offer a comprehensive discussion about the interactions that exist in their native architectures (including multicomponent and composite forms), the chemical modification of polysaccharides and their deconstruction into high axial aspect nanofibers and nanorods. We reflect on the availability and suitability of the latter types of building blocks to enable superstructures and colloidal associations. As far as processing, we describe the most relevant transitions, from the solution to the gel state and the routes that can be used to arrive to consolidated materials with prescribed properties. We highlight the implementation of supramolecular and superstructures in different technological fields that exploit the synergies exhibited by renewable polymers and biocolloids integrated in structured materials.
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Affiliation(s)
- Blaise L. Tardy
- Department
of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FI-00076 Aalto, Finland
| | - Bruno D. Mattos
- Department
of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FI-00076 Aalto, Finland
| | - Caio G. Otoni
- Department
of Physical Chemistry, Institute of Chemistry, University of Campinas, P.O. Box 6154, Campinas, São Paulo 13083-970, Brazil
- Department
of Materials Engineering, Federal University
of São Carlos, Rod. Washington Luís, km 235, São
Carlos, São Paulo 13565-905, Brazil
| | - Marco Beaumont
- School
of Chemistry and Physics, Queensland University
of Technology, 2 George
Street, Brisbane, Queensland 4001, Australia
- Department
of Chemistry, Institute of Chemistry of Renewable Resources, University of Natural Resources and Life Sciences, Vienna, A-3430 Tulln, Austria
| | - Johanna Majoinen
- Department
of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FI-00076 Aalto, Finland
| | - Tero Kämäräinen
- Department
of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FI-00076 Aalto, Finland
| | - Orlando J. Rojas
- Department
of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, P.O. Box 16300, FI-00076 Aalto, Finland
- Bioproducts
Institute, Department of Chemical and Biological Engineering, Department
of Chemistry and Department of Wood Science, University of British Columbia, 2360 East Mall, Vancouver, British Columbia V6T 1Z4, Canada
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9
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Fabrication of cellulose acetate nanocomposite films with lignocelluosic nanofiber filler for superior effect on thermal, mechanical and optical properties. ACTA ACUST UNITED AC 2021. [DOI: 10.1016/j.nanoso.2020.100642] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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10
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Sakai S, Yoshii A, Sakurai S, Horii K, Nagasuna O. Silk fibroin nanofibers: a promising ink additive for extrusion three-dimensional bioprinting. Mater Today Bio 2020; 8:100078. [PMID: 33083780 PMCID: PMC7552084 DOI: 10.1016/j.mtbio.2020.100078] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/11/2020] [Accepted: 09/12/2020] [Indexed: 12/11/2022] Open
Abstract
Here, we investigated the usefulness of silk fibroin nanofibers obtained via mechanical grinding of degummed silkworm silk fibers as an additive in bioinks for extrusion three-dimensional (3D) bioprinting of cell-laden constructs. The nanofibers could be sterilized by autoclaving, and addition of the nanofibers improved the shear thinning of polymeric aqueous solutions, independent of electric charge and the content of cross-linkable moieties in the polymers. The addition of nanofibers to bioinks resulted in the fabrication of hydrogel constructs with higher fidelity to blueprints. Mammalian cells in the constructs showed >85% viability independent of the presence of nanofibers. The nanofibers did not affect the morphologies of enclosed cells. These results demonstrate the great potential of silk fibroin nanofibers obtained via mechanical grinding of degummed silkworm silk fibers as an additive in bioinks for extrusion 3D bioprinting.
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Affiliation(s)
- S. Sakai
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-Cho, Toyonaka, Osaka, 560-8531, Japan
| | - A. Yoshii
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-Cho, Toyonaka, Osaka, 560-8531, Japan
| | - S. Sakurai
- Nagasuna Mayu Inc., Kyotango, Kyoto, 629-3101, Japan
| | - K. Horii
- Nagasuna Mayu Inc., Kyotango, Kyoto, 629-3101, Japan
| | - O. Nagasuna
- Nagasuna Mayu Inc., Kyotango, Kyoto, 629-3101, Japan
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Lai CW, Yu SS. 3D Printable Strain Sensors from Deep Eutectic Solvents and Cellulose Nanocrystals. ACS APPLIED MATERIALS & INTERFACES 2020; 12:34235-34244. [PMID: 32614162 DOI: 10.1021/acsami.0c11152] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Stretchable and conductive hydrogels have been intensively studied as wearable electronics to monitor the physiological activities of human bodies. However, it remains a challenge to fabricate robust hydrogels as sensors with complex 3D structures. Here, we designed a 3D printable ink from cellulose nanocrystals (CNCs), deep eutectic solvents (DESs), and ionically cross-linked polyacrylic acid (PAA). DESs composed of choline chloride and ethylene glycol served as a nonvolatile medium with high ionic conductivity. The dispersion of CNCs in a mixture of DESs, acrylic acid, and Al3+ ions formed ionogels with a reversible physical network for 3D printing. After the printing process, the ionogel was solidified by the photopolymerization of acrylic acid in the presence of Al3+ ions to form a second ionically cross-linked network. The first physical network of CNCs provides an energy-dissipating mechanism to make a strong and highly stretchable nanocomposite ionogel. When compared to hydrogels, we found that the DES/CNC nanocomposite ionogel was more stable in the air because of the low volatility of DESs. We further used the DES/CNC ink to 3D print an auxetic sensor with negative Poisson's ratios so that the sensor provided a conformal contact with the skin during large deformation. In addition, the auxetic sensor could continuously monitor and identify different motions of the human body by the change in resistance. These results demonstrate a simple and rapid strategy to fabricate stable and sensitive strain sensors from cheap and renewable feedstock.
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Affiliation(s)
- Chun-Wei Lai
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
| | - Sheng-Sheng Yu
- Department of Chemical Engineering, National Cheng Kung University, Tainan 70101, Taiwan
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