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1.
Int J Biol Macromol ; 280(Pt 4): 136182, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-39357735

RÉSUMÉ

This study investigates a novel all-polysaccharide hydrogel composed of tragacanth gum (TG) and cellulose nanocrystals (CNCs), eliminating the need for toxic crosslinkers. Designed for potential tissue engineering applications, these hydrogels were fabricated using 3D printing and freeze-drying techniques to create scaffolds with interconnected macropores, facilitating nutrient transport. SEM images revealed that the hydrogels contained macropores with a diameter of 100-115 µm. Notably, increasing the CNC content within the TG matrix (30-50 %) resulted in a decrease in porosity from 83 % to 76 %, attributed to enhanced polymer-nanocrystal interactions that produced denser networks. Despite the reduced porosity, the hydrogels demonstrated high swelling ratios (890-1090 %) due to the high water binding capacity of the hydrogel. Mechanical testing showed that higher CNC concentrations significantly improved compressive strength (27.7-49.5 kPa) and toughness (362-707 kJ/m3), highlighting the enhanced mechanical properties of the hydrogels. Thermal analysis confirmed stability up to 400 °C and verified ionic crosslinking with CaCl2. Additionally, hemolysis tests indicated minimal hemolytic activity, affirming the biocompatibility of the TG/CNC hydrogels. These findings highlight the potential of these hydrogels as advanced materials for 3D-printed scaffolds and injectable hydrogels, offering customizable porosity, superior mechanical strength, thermal stability, and biocompatibility.

2.
Int J Biol Macromol ; 278(Pt 1): 134402, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39094885

RÉSUMÉ

3D printed scaffolds have revolutionized the field of regenerative medicine by overcoming the lacunas such as precision, customization, and reproducibility observed through traditional methods of scaffold preparation such as freeze-drying, electrospinning, etc. Combining the advantages of 3D printed scaffolds along with bioactive cues such as signaling molecules can be an effective treatment approach. In the present study, cellulose nanocrystals (CNCs) along with gelatin, in different ratios, were used for scaffold preparation through the direct ink writing technique and thoroughly characterized. The scaffolds showed porous microstructure, high swelling ratio (∼390 to 590), degradability and porosity (∼65 %). In vitro biocompatibility assays showed high biocompatibility and no toxicity through live-dead, proliferation and hemolysis assay. Further, the optimum formulation was functionalized with nitric oxide (NO)-releasing modified gelatin to enhance the scaffold's biomedical applicability. Functionality assays with this formulation, scratch, and neurite outgrowth showed positive effects of NO on cell migration and neurite length. The study presents the fabrication, modification, and biomedical applicability of the aforementioned inks, which paves new pathways in the field of 3D printing of scaffolds with significant potential for biomedical applications, soft tissue engineering, and wound dressing, for example.


Sujet(s)
Matériaux biocompatibles , Cellulose , Gélatine , Nanoparticules , Impression tridimensionnelle , Médecine régénérative , Structures d'échafaudage tissulaires , Gélatine/composition chimique , Cellulose/composition chimique , Structures d'échafaudage tissulaires/composition chimique , Nanoparticules/composition chimique , Médecine régénérative/méthodes , Matériaux biocompatibles/composition chimique , Matériaux biocompatibles/pharmacologie , Animaux , Ingénierie tissulaire/méthodes , Prolifération cellulaire/effets des médicaments et des substances chimiques , Porosité , Humains , Hémolyse/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Monoxyde d'azote/composition chimique , Test de matériaux
3.
Int J Biol Macromol ; 279(Pt 1): 135173, 2024 Nov.
Article de Anglais | MEDLINE | ID: mdl-39214203

RÉSUMÉ

This study presents a comprehensive analysis encompassing melt blending, characterization, life cycle assessment (LCA), and 3D printing of a range of polylactic acid (PLA)/starch biocomposites, with starch content varying from 0 to 50 wt%. To enhance compatibility between the starch particles and the PLA matrix, we utilized a solvent-free method to graft N-octadecyl isocyanate (ODI) molecules onto the surface of the starch particles, resulting in ODI-g-starch, which yielded several improved properties. Notably, toughness and elongation at break improved by approximately 170 % and 300 %, respectively. Moreover, the crystallinity increased from 11.6 % in plain PLA to 30.1 %, suggesting that the uniform dispersion of ODI-g-starch particles acted as nucleating sites for the crystallization of PLA chains. Additionally, viscosity decreased significantly with the introduction of ODI-g-starch particles, indicating their plasticizing effect, thereby enhancing the processability and ease of fabrication of the biocomposite. Crucially, our LCA analysis revealed a significant reduction in the carbon footprint of these biocomposites, up to 18 % and 63 %, compared to plain PLA and selected fossil-based plastics, respectively, upon the incorporation of ODI-g-starch. In summary, our research introduces the newly developed PLA/starch biocomposites as a sustainable and eco-friendly alternative to commercially available plain PLA and specific fossil-based plastics.


Sujet(s)
Polyesters , Amidon , Polyesters/composition chimique , Amidon/composition chimique , Matériaux biocompatibles/composition chimique , Viscosité , Impression tridimensionnelle
4.
Adv Mater ; 36(38): e2405917, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39044611

RÉSUMÉ

Using light to drive polymer actuators can enable spatially selective complex motions, offering a wealth of opportunities for wireless control of soft robotics and active textiles. Here, the integration of photothermal components is reported into shape memory polymer actuators. The fabricated twist-coiled artificial muscles show on-command multidirectional bending, which can be controlled by both the illumination intensity, as well as the chirality, of the prepared artificial muscles. Importantly, the direction in which these artificial muscles bend does not depend on intrinsic material characteristics. Instead, this directionality is achieved by localized untwisting of the actuator, driven by selective irradiation. The reaction times of this bending system are significantly - at least two orders of magnitude - faster than heliotropic biological systems, with a response time up to one second. The programmability of the artificial muscles is further demonstrated for selective, reversible, and sustained actuation when integrated in butterfly-shaped textiles, along with the capacity to autonomously orient toward a light source. This functionality is maintained even on a rotating platform, with angular velocities of 6°/s, independent of the rotation direction. These attributes collectively represent a breakthrough in the field of artificial muscles, intended to adaptive shape-changing soft systems and biomimetic technologies.


Sujet(s)
Lumière , Robotique , Muscles/physiologie , Textiles , Polymères/composition chimique , Matériaux biomimétiques/composition chimique , Matériaux biomimétiques/effets des radiations , Biomimétique/méthodes , Organes artificiels
5.
Int J Biol Macromol ; 275(Pt 1): 133480, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38942408

RÉSUMÉ

This study investigates the conversion of highly acetylated sugarcane bagasse into high-modulus carbon nanofibers (CnNFs) with exceptional electrical conductivity. By electrospinning the bagasse into nanofibers with diameters ranging from 80 nm to 800 nm, a cost-effective CnNFs precursor is obtained. The study reveals the transformation of the cellulose crystalline structure into a stable antiparallel chain arrangement of cellulose II following prolonged isothermal treatment, leading to a remarkable 50 % increase in CnNFs recovery with carbon contents ranging from 80 % to 90 %. This surpasses the performance of any other reported biomass precursors. Furthermore, graphitization-induced shrinkage of CnNFs diameter results in significant growth of specific surface area and pore volume in the resulting samples. This, along with a highly ordered nanostructure and high crystallinity degree, contributes to an impressive tensile modulus of 9.592 GPa, surpassing that of most petroleum-based CnNFs documented in the literature. Additionally, the prolonged isothermal treatment influences the d002 value (measured at 0.414 nm) and CnNFs degree of crystallinity, leading to an enhancement in electrical conductivity. However, the study observes no size effect advantages on mechanical properties and electrical conductivity, possibly attributed to the potential presence of point defects in the ultrathin CnNFs. Overall, this research opens a promising and cost-effective pathway for converting sugarcane biomasses into high-modulus carbon nanofibers with outstanding electrical conductivity. These findings hold significant implications for the development of sustainable and high-performance materials for various applications, including electronics, energy storage, and composite reinforcement.


Sujet(s)
Carbone , Cellulose , Nanofibres , Nanofibres/composition chimique , Cellulose/composition chimique , Carbone/composition chimique , Conductivité électrique , Biomasse , Saccharum/composition chimique , Température , Résistance à la traction
6.
Int J Biol Macromol ; 265(Pt 1): 130750, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38467224

RÉSUMÉ

The study explores the use of hydrochar-derived activated carbon (AC) to improve the adsorption capacity and mechanical properties of carrageenan (CAR) hydrogel beads. Four distinct samples, with carrageenan to activated carbon ratios of 1:0 (CAR), 2:1 (CAC2), 4:1 (CAC4), and 10:1 (CAC10), were prepared. These polymeric beads underwent comprehensive evaluation for their methylene blue (MB) adsorption capacity, gel content (GC), and swelling ratio (SR). Increasing activated carbon content up to 50 % of carrageenan mass significantly enhanced GC and SR by 20.57 % and 429.24 %, respectively. Various analytical techniques were employed to characterize the composites, including FTIR, XRD, Raman Spectroscopy, BET, SEM, and EDS-Mapping. Batch adsorption tests investigated the effects of pH, contact time, dye concentration, and temperature on MB adsorption. Maximum adsorption capacities for CAR, CAC10, CAC4, and CAC2 were 475.48, 558.54, 635.93, and 552.35 mg/g, respectively, under optimal conditions. Kinetic models (Elovich and pseudo-second-order) and isotherm models (Temkin for CAR and Freundlich for CAC10, CAC4, and CAC2) fitted well with the experimental data. Thermodynamic analysis showed spontaneous, exothermic MB adsorption. Primary mechanisms include electrostatic attraction, hydrogen bonding, n-π, and π-π stacking. The study highlights enhanced adsorption capacity of carrageenan hydrogel via carrageenan/activated carbon composites, providing cost-effective wastewater treatment.


Sujet(s)
Hydrogels , Polluants chimiques de l'eau , Bleu de méthylène/composition chimique , Charbon de bois , Carragénane/composition chimique , Adsorption , Polluants chimiques de l'eau/analyse , Concentration en ions d'hydrogène , Cinétique
7.
Adv Colloid Interface Sci ; 324: 103095, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38301316

RÉSUMÉ

Direct ink writing (DIW) stands as a pioneering additive manufacturing technique that holds transformative potential in the field of hydrogel fabrication. This innovative approach allows for the precise deposition of hydrogel inks layer by layer, creating complex three-dimensional structures with tailored shapes, sizes, and functionalities. By harnessing the versatility of hydrogels, DIW opens up possibilities for applications spanning from tissue engineering to soft robotics and wearable devices. This comprehensive review investigates DIW as applied to hydrogels and its multifaceted applications. The paper introduces a diverse range of printing techniques while providing a thorough exploration of DIW for hydrogel-based printing. The investigation aims to explain the progress made, challenges faced, and potential trajectories that lie ahead for DIW in hydrogel-based manufacturing. The fundamental principles underlying DIW are carefully examined, specifically focusing on rheological attributes and printing parameters, prompting a comprehensive survey of the wide variety of hydrogel materials. These encompass both natural and synthetic variations, all of which can be effectively harnessed for this purpose. Furthermore, the review explores the latest applications of DIW for hydrogels in biomedical areas, with a primary focus on tissue engineering, wound dressing, and drug delivery systems. The document not only consolidates the existing state of DIW within the context of hydrogel-based manufacturing but also charts potential avenues for further research and innovative breakthroughs.


Sujet(s)
Hydrogels , Encre , Hydrogels/composition chimique , Impression tridimensionnelle , Ingénierie tissulaire/méthodes , Rhéologie
8.
Green Chem ; 26(2): 593-630, 2024 Jan 22.
Article de Anglais | MEDLINE | ID: mdl-38264324

RÉSUMÉ

The demand for biodegradable materials across various industries has recently surged due to environmental concerns and the need for the adoption of renewable materials. In this context, lignin has emerged as a promising alternative, garnering significant attention as a biogenic resource that endows functional properties. This is primarily ascribed to its remarkable origin and structure that explains lignin's capacity to bind other molecules, reinforce composites, act as an antioxidant, and endow antimicrobial effects. This review summarizes recent advances in lignin-based composites, with particular emphasis on innovative methods for modifying lignin into micro and nanostructures and evaluating their functional contribution. Indeed, lignin-based composites can be tailored to have superior physicomechanical characteristics, biodegradability, and surface properties, thereby making them suitable for applications beyond the typical, for instance, in ecofriendly adhesives and advanced barrier technologies. Herein, we provide a comprehensive overview of the latest progress in the field of lignin utilization in emerging composite materials.

9.
ACS Appl Mater Interfaces ; 15(41): 48584-48600, 2023 Oct 18.
Article de Anglais | MEDLINE | ID: mdl-37787649

RÉSUMÉ

This study introduces the development of a thermally responsive shape-morphing fabric using low-melting-point polyamide shape memory actuators. To facilitate the blending of biomaterials, we report the synthesis and characterization of a biopolyamide with a relatively low melting point. Additionally, we present a straightforward and solvent-free method for the compatibilization of starch particles with the synthesized biopolyamide, aiming to enhance the sustainability of polyamide and customize the actuation temperature. Subsequently, homogeneous dispersion of up to 70 wt % compatibilized starch particles into the matrix is achieved. The resulting composites exhibit excellent mechanical properties comparable to those reported for soft and tough materials, making them well suited for textile integration. Furthermore, cyclic thermomechanical tests were conducted to evaluate the shape memory and shape recovery of both plain polyamide and composites. The results confirmed their remarkable shape recovery properties. To demonstrate the potential application of biocomposites in textiles, a heat-responsive fabric was created using thermoresponsive shape memory polymer actuators composed of a biocomposite containing 50 wt % compatibilized starch. This fabric demonstrates the ability to repeatedly undergo significant heat-induced deformations by opening and closing pores, thereby exposing hidden functionalities through heat stimulation. This innovative approach provides a convenient pathway for designing heat-responsive textiles, adding value to state-of-the-art smart textiles.

10.
Biomacromolecules ; 24(11): 4901-4914, 2023 11 13.
Article de Anglais | MEDLINE | ID: mdl-37874127

RÉSUMÉ

Traditional metal-alloy bone fixation devices provide structural support for bone repair but have limitations in actively promoting bone healing and often require additional surgeries for implant removal. In this study, we focused on addressing these challenges by fabricating biodegradable composites using poly(lactic acid) (PLA) and strontium-substituted nanohydroxyapatite (SrHAP) via melt compounding and injection molding. Various percentages of SrHAP (5, 10, 20, and 30% w/w) were incorporated into the PLA matrix. We systematically investigated the structural, morphological, thermal, mechanical, rheological, and dynamic mechanical properties of the prepared composites. Notably, the tensile modulus, a critical parameter for orthopedic implants, significantly improved from 2.77 GPa in pristine PLA to 3.73 GPa in the composite containing 10% w/w SrHAP. The incorporation of SrHAP (10% w/w) into the PLA matrix led to an increased storage modulus, indicating a uniform dispersion of SrHAP within the PLA and good compatibility between the polymer and nanoparticles. Moreover, we successfully fabricated screws using PLA composites with 10% (w/w) SrHAP, demonstrating their formability at room temperature and radiopacity when observed under X-ray microtomography (micro-CT). Furthermore, the water contact angle decreased from 93 ± 2° for pristine PLA to 75 ± 3° for the composite containing SrHAP, indicating better surface wettability. To assess the biological behavior of the composites, we conducted in vitro cell-material tests, which confirmed their osteoconductive and osteoinductive properties. These findings highlight the potential of our developed PLA/SrHAP10 (10% w/w) composites as machinable implant materials for orthopedic applications. In conclusion, our study presents the fabrication and comprehensive characterization of biodegradable composites comprising PLA and strontium-substituted nanohydroxyapatite (SrHAP). These composites exhibit improved mechanical properties, formability, and radiopacity while also demonstrating desirable biological behavior. Our results suggest that these PLA/SrHAP10 composites hold promise as machinable implant materials for orthopedic applications.


Sujet(s)
Polyesters , Strontium , Polyesters/composition chimique , Polymères/composition chimique , Prothèses et implants
11.
Int J Biol Macromol ; 209(Pt B): 2020-2031, 2022 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-35500781

RÉSUMÉ

The current study provides a comprehensive rheology study and a survey on direct ink writing of xanthan gum/cellulose nanocrystal (XG/CNC) bio-inks for developing 3D geometries that mimic soft tissue engineering scaffolds' physical and mechanical properties. The presence of CNC was found to be a critical prerequisite for the printability of XG bio-inks; accordingly, the hybrid XG/CNC bio-inks revealed the excellent viscoelastic properties that enabled precise control of hydrogel shaping and printing of lattice structures composed of up to eleven layers with high fidelity and fair resolution without any deformation after printing. The lyophilized 3D scaffolds presented a porous structure with open and interconnected pores and a porosity higher than 70%, vital features for tissue engineering scaffolds. Moreover, they showed a relatively high swelling of approximately 11 g/g, facilitating oxygen and nutrient exchange. Furthermore, the elastic and compressive moduli of the scaffolds that enhanced significantly upon increasing CNC content were in the range of a few kPa, similar to soft tissues. Finally, no significant cell cytotoxicity was observed against human liver cancer cells (HepG2), highlighting the potential of these developed 3D printed scaffolds for soft tissue engineering applications.


Sujet(s)
Encre , Impression tridimensionnelle , Cellulose/composition chimique , Excipients , Humains , Hydrogels/composition chimique , Polyosides bactériens/composition chimique , Ingénierie tissulaire , Structures d'échafaudage tissulaires/composition chimique
12.
J Wound Care ; 30(Sup9a): XIIIi-XIIIx, 2021 Sep 02.
Article de Anglais | MEDLINE | ID: mdl-34597172

RÉSUMÉ

OBJECTIVE: Providing a suitable environment to improve the healing process is the main target of wound dressing that also protects the wound from additional harms. In the present study, fabrication and characterisation of a new kind of electrospun wound dressing composed of polyvinyl alcohol (PVA) and quince seed mucilage (QSM) is reported. METHOD: QSM was extracted from quince seeds, purified, freeze-dried and used to produce aqueous solutions containing different amounts of PVA and QSM. The wound dressings were fabricated via the electrospinning method and their characteristics were investigated with scanning electron microscope (SEM) images, Fourier transform infrared (FTIR) spectra, tensile and swelling test, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cytotoxicity assay against fibroblast cells. RESULTS: SEM images confirmed that proper, uniform, non-oriented nanofibres with an average diameter in the range of 60-240nm, depending on the QSM content had been fabricated. The tensile test showed that with increasing QSM content, the tensile strength of fibre increased while elongation at break was decreased, which was consistent with SEM images where the diameter of samples decreased by increasing QSM content. MTT assay showed significant biocompatibility against fibroblast cells; however, it was increased by increased QSM proportion. In addition, SEM images supported the proper adhesion of fibroblast cells on the sample one day after culturing. CONCLUSION: Overall, the findings of the current study support the potential of PVA/QSM nanofibres as a proper candidate for biomedical applications, especially as a wound dressing.


Sujet(s)
Poly(alcool vinylique) , Rosaceae , Bandages , Graines , Cicatrisation de plaie
13.
Mater Sci Eng C Mater Biol Appl ; 130: 112424, 2021 Nov.
Article de Anglais | MEDLINE | ID: mdl-34702510

RÉSUMÉ

We proposed a simple method to process hydrogels containing polyvinyl alcohol and cellulose nanofibrils (PVA/CNF) to prepare volumetric architectures by direct ink writing (DIW). The presence of CNF in the aqueous PVA suspensions conferred rheology profiles that were suitable for extrusion and solidification in pre-designed shapes. The viscoelastic behavior of the hybrid inks enabled precise control on processability and shape retention, for instance, as demonstrated in multilayered lattice structures of high fidelity. After lyophilization, the obtained 3D-printed hydrogels presented a very high porosity, with open and interconnected pores, allowing a high-water uptake capacity (up to 1600%). The mechanical strength of the composite 3D-printed materials matched those of soft tissues, opening opportunities for skin applications. As such, drug-loaded samples revealed a controlled and efficient delivery of an antioxidant (ascorbic acid) in PBS buffer media at 23 °C (~80% for 8 h). Altogether, PVA/CNF hydrogels were introduced as suitable precursors of 3D-lattice geometries with excellent physical and mechanical characteristics.


Sujet(s)
Cellulose , Poly(alcool vinylique) , Acide ascorbique , Hydrogels , Impression tridimensionnelle
14.
Int J Biol Macromol ; 192: 1098-1107, 2021 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-34666132

RÉSUMÉ

Plant-based hydrogels have attracted great attention in biomedical fields since they are biocompatible and based on natural, sustainable, cost-effective, and widely accessible sources. Here, we introduced new viscoelastic bio-inks composed of quince seed mucilage and cellulose nanofibrils (QSM/CNF) easily extruded into 3D lattice structures through direct ink writing in ambient conditions. The QSM/CNF inks enabled precise control on printing fidelity where CNF endowed objects with shape stability after freeze-drying and with suitable porosity, water uptake capacity, and mechanical strength. The compressive and elastic moduli of samples produced at the highest CNF content were both increased by ~100% (from 5.1 ± 0.2 kPa and 32 ± 1 kPa to 10.7 ± 0.5 and 64 ± 2 kPa, respectively). These values ideally matched those reported for soft tissues; accordingly, the cell compatibility of the printed samples was evaluated against HepG2 cells (human liver cancer). The results confirmed the 3D hydrogels as being non-cytotoxic and suitable to support attachment, survival, and proliferation of the cells. All in all, the newly developed inks allowed sustainable 3D bio-hydrogels fitting the requirements as scaffolds for soft tissue engineering.


Sujet(s)
Cellulose/composition chimique , Hydrogels/composition chimique , Nanofibres/composition chimique , Mucilage des plantes/composition chimique , Impression tridimensionnelle , Rosaceae/composition chimique , Lignée cellulaire tumorale , Phénomènes chimiques , Humains , Nanofibres/ultrastructure , Porosité , Rhéologie , Analyse spectrale , Structures d'échafaudage tissulaires
15.
J Biomater Appl ; 36(5): 803-817, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34121491

RÉSUMÉ

In the present study, alginate/cartilage extracellular matrix (ECM)-based injectable hydrogel was developed incorporated with silk fibroin nanofibers (SFN) for cartilage tissue engineering. The in situ forming hydrogels were composed of different ionic crosslinked alginate concentrations with 1% w/v enzymatically crosslinked phenolized cartilage ECM, resulting in an interpenetrating polymer network (IPN). The response surface methodology (RSM) approach was applied to optimize IPN hydrogel's mechanical properties by varying alginate and SFN concentrations. The results demonstrated that upon increasing the alginate concentration, the compression modulus improved. The SFN concentration was optimized to reach a desired mechanical stiffness. Accordingly, the concentrations of alginate and SFN to have an optimum compression modulus in the hydrogel were found to be 1.685 and 1.724% w/v, respectively. The gelation time was found to be about 10 s for all the samples. Scanning electron microscope (SEM) images showed homogeneous dispersion of the SFN in the hydrogel, mimicking the natural cartilage environment. Furthermore, water uptake capacity, degradation rate, cell cytotoxicity, and glycosaminoglycan and collagen II secretions were determined for the optimum hydrogel to support its potential as an injectable scaffold for articular cartilage defects.


Sujet(s)
Alginates , Cartilage , Matrice extracellulaire , Hydrogels/composition chimique , Polymères/composition chimique , Ingénierie tissulaire/méthodes , Cartilage/effets des médicaments et des substances chimiques , Cartilage articulaire , Chondrocytes/effets des médicaments et des substances chimiques , Collagène/métabolisme , Matrice extracellulaire/effets des médicaments et des substances chimiques , Fibroïne , Glycosaminoglycanes , Hydrogels/pharmacologie , Polymères/pharmacologie , Structures d'échafaudage tissulaires
16.
Carbohydr Polym ; 266: 118114, 2021 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-34044931

RÉSUMÉ

Direct-ink-writing (DIW) of hydrogels has become an attractive research area due to its capability to fabricate intricate, complex, and highly customizable structures at ambient conditions for various applications, including biomedical purposes. In the current study, cellulose nanofibrils reinforced aloe vera bio-hydrogels were utilized to develop 3D geometries through the DIW technique. The hydrogels revealed excellent viscoelastic properties enabled extruding thin filaments through a nozzle with a diameter of 630 µm. Accordingly, the lattice structures were printed precisely with a suitable resolution. The 3D-printed structures demonstrated significant wet stability due to the high aspect ratio of the nano- and microfibrils cellulose, reinforced the hydrogels, and protected the shape from extensive shrinkage upon drying. Furthermore, all printed samples had a porosity higher than 80% and a high-water uptake capacity of up to 46 g/g. Altogether, these fully bio-based, porous, and wet stable 3D structures might have an opportunity in biomedical fields.


Sujet(s)
Aloe/composition chimique , Cellulose/composition chimique , Hydrogels/composition chimique , Encre , Nanofibres/composition chimique , Impression tridimensionnelle , Porosité , Substances viscoélastiques/composition chimique , Viscosité
17.
J Biomater Appl ; 33(5): 619-629, 2018 11.
Article de Anglais | MEDLINE | ID: mdl-30388384

RÉSUMÉ

Peripheral nervous system in contrary to central one has the potential for regeneration, but its regrowth requires proper environmental conditions and supporting growth factors. The aim of this study is to design and fabricate a conductive polyaniline/graphene nanoparticles incorporated gelatin nanofibrous scaffolds suitable for peripheral nervous system regeneration. The scaffolds were fabricated with electrospinning and the fabrication process was designed with Design-Expert software via response surface methodology. The effect of process parameters including applied voltage (kV), syringe pump flow rate (cm3/h), and PAG concentration (wt%), on the scaffold conductivity, nanofibers diameter, and cell viability were investigated. The obtained results showed that the scaffold conductivity and cell viability are affected by polyaniline/graphene concentration while nanofiber diameter is more affected by the applied voltage and syringe pump flow rate. Optimum scaffold with maximum conductivity (0.031 ± 0.0013 S/cm) and cell compatibility and suitable diameter were electrospun according to the software introduced values for the process parameters (voltage of 13 kV, flow rate of 0.1 cm3/h, and PAG wt.% of 1.3) and its morphology, cell compatibility, and biodegradability were further investigated, which showed its potential for applying in peripheral nervous system injury regeneration.


Sujet(s)
Dérivés de l'aniline/composition chimique , Gélatine/composition chimique , Graphite/composition chimique , Cellules souches mésenchymateuses/cytologie , Nanofibres/composition chimique , Structures d'échafaudage tissulaires/composition chimique , Animaux , Lignée cellulaire , Survie cellulaire , Conductivité électrique , Souris , Nanofibres/ultrastructure , Régénération nerveuse , Ingénierie tissulaire/méthodes
18.
Int J Biol Macromol ; 109: 1019-1028, 2018 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-29154877

RÉSUMÉ

In this study, we reported the design and fabrication of starch/gelatin/graphene oxide biodegradable nanocomposite films with proper potential for food packaging applications. The experiments were designed using Design Expert software via RSM by defining gelatin/starch weight ratio (G/S wt. ratio) and graphene oxide (GO) wt.% as process parameters affecting on the properties of the prepared films. The optimization was done and various properties of the optimum film were investigated. The XRD and SEM images confirmed that GO layers could intercalate in the starch/gelatin matrix and proper dispersion of nanofillers in the matrix obtained via solution casting method. The mechanical strength, thermal stability, surface hydrophilicity, and water vapor permeability were improved in the present of GO which could be related to reinforcing effect and proper barrier property of GO. Degradation of the prepared films under the soil was investigated during 6 weeks and the results indicated at least 30% weight loss happened throughout the test duration. Overall, the obtained results corroborate that the starch/gelatin/GO compounding can be a good candidate for fabricating of biodegradable nanocomposite films for food packaging applications.


Sujet(s)
Gélatine/composition chimique , Graphite/composition chimique , Nanocomposites/composition chimique , Oxydes/composition chimique , Amidon/composition chimique , Interactions hydrophobes et hydrophiles , Phénomènes mécaniques , Nanocomposites/ultrastructure , Spectroscopie infrarouge à transformée de Fourier , Résistance à la traction , Thermogravimétrie , Diffraction des rayons X
19.
Int J Biol Macromol ; 88: 288-95, 2016 Jul.
Article de Anglais | MEDLINE | ID: mdl-27037056

RÉSUMÉ

Porous gelatin-chitosan microcarriers (MCs) with the size of 350±50µm were fabricated with blends of different gelatin/chitosan (G/C) weight ratio using an electrospraying technique. Response surface methodology (RSM) was used to study the quantitative influence of process parameters, including blend ratio, voltage, and syringe pump flow rate, on MCs diameter and density. In the following, MCs of the same diameter and different G/C weight ratio (1, 2, and 3) were fabricated and their porosity and biocompatibility were investigated via SEM images and MTT assay, respectively. The results showed that mesenchymal stem cells (MSCs) could attach, proliferate, and spread on fabricated porous MCs during 7 days of culturing especially on those prepared with a G/C weight ratio of 1. Such porous gelatin-chitosan MCs with a G/C weight ratio of 1 may be considered as a promising candidate for injectable carriers supporting attachment and proliferation of MSCs.


Sujet(s)
Chitosane/composition chimique , Vecteurs de médicaments , Gélatine/composition chimique , Cellules souches mésenchymateuses/effets des médicaments et des substances chimiques , Structures d'échafaudage tissulaires , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Chitosane/pharmacologie , Techniques électrochimiques , Analyse statistique factorielle , Femelle , Gélatine/pharmacologie , Humains , Cellules souches mésenchymateuses/cytologie , Porosité , Grossesse , Culture de cellules primaires , Cordon ombilical/cytologie , Cordon ombilical/effets des médicaments et des substances chimiques
20.
J Biomater Appl ; 31(1): 152-61, 2016 07.
Article de Anglais | MEDLINE | ID: mdl-26916948

RÉSUMÉ

In this study, we reported the preparation of self cross-linked oxidized alginate-gelatin hydrogels for muscle tissue engineering. The effect of oxidation degree (OD) and oxidized alginate/gelatin (OA/GEL) weight ratio were examined and the results showed that in the constant OA/GEL weight ratio, both cross-linking density and Young's modulus enhanced by increasing OD due to increment of aldehyde groups. Furthermore, the degradation rate was increased with increasing OD probably due to decrement in alginate molecular weight during oxidation reaction facilitated degradation of alginate chains. MTT cytotoxicity assays performed on Wharton's Jelly-derived umbilical cord mesenchymal stem cells cultured on hydrogels with OD of 30% showed that the highest rate of cell proliferation belong to hydrogel with OA/GEL weight ratio of 30/70. Overall, it can be concluded from all obtained results that the prepared hydrogel with OA/GEL weight ratio and OD of 30/70 and 30%, respectively, could be proper candidate for use in muscle tissue engineering.


Sujet(s)
Alginates/composition chimique , Matériaux biocompatibles/synthèse chimique , Gélatine/composition chimique , Hydrogels/synthèse chimique , Cellules souches mésenchymateuses/physiologie , Muscles squelettiques/croissance et développement , Ingénierie tissulaire/méthodes , Différenciation cellulaire/physiologie , Cellules cultivées , Résistance à la compression , Réactifs réticulants/composition chimique , Acide glucuronique/composition chimique , Acides hexuroniques/composition chimique , Humains , Test de matériaux , Cellules souches mésenchymateuses/cytologie , Muscles squelettiques/cytologie , Oxydoréduction , Contrainte mécanique , Résistance à la traction
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