| 1. |
- Abbaszad Rafi, Abdolrahim, et al.
(författare)
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Photo-Switchable Nanomechanical Systems Comprising a Nanocontainer (Montmorillonite) and Light-Driven Molecular Jack (Azobenzene-Imidazolium Ionic Liquids) as Drug Delivery Systems; Synthesis, Characterization, and in Vitro Release Studies
- 2018
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society. - 2373-9878. ; 4:1, s. 184-192
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Tidskriftsartikel (refereegranskat)abstract
- In this work, photoresponsive nanomechanical systems were prepared through the intercalation of positively charged photoswitching molecular jacks (azobenzene ionic liquids, Azo-ILs) within montmorillonite (MMT) layers (MMT@Azo-ILs). The study shows that MMT@Azo-ILs are photosensitive and the synthesized molecular jacks could change the basal distances of MMT layers upon UV irradiation. These changes come from changes in the structure and geometry of Azo molecules (i.e., cis-trans isomerization) between clay layers upon UV irradiation. The prepared photoresponsive nanomechanical systems were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDX), field-emission scanning electron microscope (FE-SEM). Moreover, the in vitro release studies were performed in different conditions (upon UV irradiation and darkness) in pH 5.8 at 34 ± 1 °C, and it was found that the release rates from drug loaded MMT@Azo-ILs were higher upon UV irradiation in comparison with the release rates in darkness. According to the release studies, the prepared photoresponsive carriers might be considered as an excellent potential candidate in order to formulate smart sunscreens. © 2017 American Chemical Society.
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| 2. |
- Aminoroaya, Alireza, et al.
(författare)
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A Review of Dental Composites : Methods Of Characterizations
- 2020
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 6:7, s. 3713-3744
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Forskningsöversikt (refereegranskat)abstract
- Dental composites are becoming increasingly popular in esthetic restorative dentistry and present a promising substitute for amalgam. However, the major hurdles that hinder their total adoption in restorative dentistry are limited longevity and possible health risks, leading to significant attempts for addressing these shortcomings. Besides the new materials, the evaluation methods play a critical role in the introduction and improvement of these types of materials. This review aims to cover the characterization methods in the evaluation of dental composites that are most employed nowadays. Therefore, the methods for evaluating the physical properties of the dental composites are first explained. Subsequently, the assessment methods of curing kinetics and the mechanical properties of the composites are classified and reviewed. Afterward, the article delves into the introduction and classification of the microscopic and antibacterial evaluation methods. Finally, the test methods for assessment of in vitro cytotoxicity and self-healing ability are described. It should be noted, for each test method, the most recent and interesting articles are cited. It is envisaged that this review will facilitate an understanding and provide knowledge for the section and utilizing the most effective and suitable characterization methods for future research on the development of dental composites.
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| 3. |
- Apelgren, Peter, et al.
(författare)
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In Vivo Human Cartilage Formation in Three-Dimensional Bioprinted Constructs with a Novel Bacterial Nanocellulose Bioink
- 2019
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Ingår i: Acs Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:5, s. 2482-2490
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Tidskriftsartikel (refereegranskat)abstract
- Bacterial nanocellulose (BNC) is a 3D network of nanofibrils exhibiting excellent biocompatibility. Here, we present the aqueous counter collision (ACC) method of BNC disassembly to create bioink with suitable properties for cartilage-specific 3D-bioprinting. BNC was disentangled by ACC, and fibril characteristics were analyzed. Bioink printing fidelity and shear-thinning properties were evaluated. Cell-laden bioprinted grid constructs (5 X 5 X 1 mm(3)) containing human nasal chondrocytes (10 M mL(-1)) were implanted in nude mice and explanted after 30 and 60 days. Both ACC and hydrolysis resulted in significantly reduced fiber lengths, with ACC resulting in longer fibrils and fewer negative charges relative to hydrolysis. Moreover, ACC-BNC bioink showed outstanding printability, postprinting mechanical stability, and structural integrity. In vivo, cell-laden structures were rapidly integrated, maintained structural integrity, and showed chondrocyte proliferation, with 32.8 +/- 13.8 cells per mm(2) observed after 30 days and 85.6 +/- 30.0 cells per mm(2) at day 60 (p = 0.002). Furthermore, a full-thickness skin graft was attached and integrated completely on top of the 3D-bioprinted construct. The novel ACC disentanglement technique makes BNC biomaterial highly suitable for 3D-bioprinting and clinical translation, suggesting cell-laden 3D-bioprinted ACC-BNC as a promising solution for cartilage repair.
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| 4. |
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| 5. |
- Atefyekta, Saba, 1987, et al.
(författare)
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Antimicrobial Peptide-Functionalized Mesoporous Hydrogels
- 2021
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 7:4, s. 1693-1702
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Tidskriftsartikel (refereegranskat)abstract
- Antimicrobial peptides (AMPs) are seen as a promising replacement to conventional antibiotics for the prevention of skin wound infections. However, due to the short half-life of AMPs in biological environments, such as blood, their use in clinical applications has been limited. The covalent immobilization of AMPs onto suitable substrates is an effective solution to create contact-killing surfaces with increased long-term stability. In this work, an antimicrobial peptide, RRPRPRPRPWWWW-NH2 (RRP9W4N), was covalently attached to amphiphilic and ordered mesoporous Pluronic F127 hydrogels made of cross-linked lyotropic liquid crystals through 1-ethyl-3-(3-(dimethylamino)propyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) chemistry. The AMP-hydrogels showed high antibacterial activity against Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, methicillin-resistant S. aureus (MRSA), and multidrug-resistant Escherichia coli for up to 24 h. Furthermore, the AMP-hydrogels did not present any toxicity to human fibroblasts. The AMPs retained their antimicrobial activity up to 48 h in human blood serum, which is a significant increase in stability compared to when used in dissolved state. A pilot in vivo rat model showed 10-100x less viable counts of S. aureus on AMP-hydrogels compared with control hydrogels during the first 3 days of infection. Studies performed on human whole blood showed that blood coagulated more readily in the presence of AMP-hydrogels as compared to hydrogels without AMPs, indicating potential hemostatic activity. Overall, the results suggest that the combination of amphiphilic hydrogels with covalently bonded AMPs has potential to be used as antibacterial wound dressing material to reduce infections and promote hemostatic activity as an alternative to antibiotics or other antimicrobial agents, whose use should be restricted.
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| 6. |
- Berg, Camilla, et al.
(författare)
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Amorphous Calcium Magnesium Phosphate Particles for Treatment of Dentin Hypersensitivity : A Mode of Action Study
- 2020
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Ingår i: ACS Biomaterials Science & Engineering. - : AMER CHEMICAL SOC. - 2373-9878. ; 6:6, s. 3599-3607
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Tidskriftsartikel (refereegranskat)abstract
- Occlusion of exposed dentin tubules may eliminate or reduce dentin hypersensitivity by hindering fluid movements within the tubules. In this study, the mode of action of spherical particles of amorphous calcium magnesium phosphate (180-440 nm in diameter) was studied. A degradation study of the particles in Tris-HCl buffer showed that the particles continuously released Ca2+, Mg2+, and phosphate, and XRD analysis revealed the formation of hydroxyapatite (HA) after 1 week. The occluding effect and efficacy of the spherical particles as an occluding agent were evaluated in an in vitro study. The ACMP particles were incorporated in a gel intended for at-home use and tested on extracted human molars. Application of the particles followed by incubation in artificial saliva resulted in occlusion of exposed tubules, and examination with SEM showed that the particles could penetrate the tubules down to 100 mu m from the dentin surface. Transformation of the particles into nanocrystalline HA-structures (nanoHA) was initiated at the dentin surface within 12 h of application, and tubule penetration of the particles, accompanied by further ion release and diffusion of ions, resulted in deep intratubular occlusion in the majority of the tubules within 3 days from application. NanoHA was tightly adhered to the tubule walls, filling the entire tubule volume after 7 days. The results of this study demonstrate the mode of action of the amorphous calcium magnesium phosphate particles in occluding exposed dentin tubules. Interaction with saliva and transformation of the particles within the tubules inducing further mineralization indicate that the particles may be used as an effective treatment to reduce dentin hypersensitivity.
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| 7. |
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| 8. |
- Carville, N. Craig, et al.
(författare)
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Biocompatible Gold Nanoparticle Arrays Photodeposited on Periodically Proton Exchanged Lithium Niobate
- 2016
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 2:8, s. 1351-1356
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Tidskriftsartikel (refereegranskat)abstract
- Photodeposition of silver nanoparticles onto chemically patterned lithium niobate having alternating lithium niobate and proton exchanged regions has been previously investigated. Here, the spatially defined photodeposition of gold nanoparticles onto periodically proton exchanged lithium niobate is demonstrated. It is shown that the location where the gold nanoparticles form can be tailored by altering the concentration of HAuCl4. This enables the possibility to sequentially deposit gold and silver in different locations to create bimetallic arrays. The cytocompatibility of photodeposited gold, silver, and bimetallic ferroelectric templates to osteoblast-like cells is also investigated. Gold samples provide significantly greater cell biocompatibility than silver samples. These results highlight a potential route for using photodeposited gold on lithium niobate as a template for applications in cellular biosensing.
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| 9. |
- Chen, Jialin, et al.
(författare)
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Hydroxycamptothecin and substratum stiffness synergistically regulate fibrosis of human corneal fibroblasts
- 2023
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 9:2, s. 959-967
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Tidskriftsartikel (refereegranskat)abstract
- Corneal fibrosis is a common outcome of inappropriate repair associated with trauma or ocular infection. Altered biomechanical properties with increased corneal stiffness is a feature of fibrosis that cause corneal opacities, resulting in severe visual impairment and even blindness. The present study aims to determine the effect of hydroxycamptothecin (HCPT) and matrix stiffness on transforming growth factor-β1 (TGF-β1)-induced fibrotic processes in human corneal fibroblasts (HTK cells). HTK cells were cultured on substrates with different stiffnesses ("soft", ∼261 kPa; "stiff", ∼2.5 × 103 kPa) and on tissue culture plastic (TCP, ∼106 kPa) and simultaneously treated with or without 1 μg/mL HCPT and 10 ng/mL TGF-β1. We found that HCPT induced decreased cell viability and antiproliferative effects on HTK cells. TGF-β1-induced expression of fibrosis-related genes (FN1, ACTA2) was reduced if the cells were simultaneously treated with HCPT. Substrate stiffness did not affect the expression of fibrosis-related genes. The TGF-β1 induced expression of FN1 on both soft and stiff substrates was reduced if cells were simultaneously treated with HCPT. However, this trend was not seen for ACTA2, i.e., the TGF-β1 induced expression of ACTA2 was not reduced by simultaneous treatment of HCPT in either soft or stiff substrate. Instead, HCPT treatment in the presence of TGF-β1 resulted in increased gene expression of keratocyte phenotype makers (LUM, KERA, AQP1, CHTS6) on both substrate stiffnesses. In addition, the protein expression of keratocyte phenotype makers LUM and ALDH3 was increased in HTK cells simultaneously treated with TGF-β1 and HCPT on stiff substrate as compared to control, i.e., without HCPT. In conclusion, we found that HCPT can reduce TGF-β1-induced fibrosis and promote the keratocyte phenotype in a substrate stiffness dependent manner. Thus, HCPT stimulation might be an approach to stimulate keratocytes in the appropriate healing stage to avoid or reverse fibrosis and achieve more optimal corneal wound healing.
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| 10. |
- Chen, Jialin, et al.
(författare)
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Regulation of Keratocyte Phenotype and Cell Behavior by Substrate Stiffness
- 2020
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 6:9, s. 5162-5171
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Tidskriftsartikel (refereegranskat)abstract
- Corneal tissue engineering is an alternative way to solve the problem of lack of corneal donor tissue in corneal transplantation. Keratocytes with a normal phenotype and function in tissue-engineered cornea would be critical for corneal regeneration. Although the role of extracellular/substrate material stiffness is well-known for the regulation of the cell phenotype and cell behavior in many different cell types, its effects in keratocyte culture have not yet been thoroughly studied. This project studied the effect of substrate stiffness on the keratocyte phenotype marker expression and typical cell behavior (cell adhesion, proliferation, and migration), and the possible mechanisms involved. Human primary keratocytes were cultured on tissue culture plastic (TCP, similar to 10(6) kPa) or on plates with the stiffness equivalent of physiological human corneal stroma (25 kPa) or vitreous body (1 kPa). The expression of keratocyte phenotype markers, cell adhesion, proliferation, and migration were compared. The results showed that the stiffness of the substrate material regulates the phenotype marker expression and cell behavior of cultured keratocytes. Physiological corneal stiffness (25 kPa) superiorly preserved the cell phenotype when compared to the TCP and 1 kPa group. Keratocytes had a larger cell area when cultured on 25 kPa plates as compared to on TCP. Treatment of cells with NSC 23766 (Rac1 inhibitor) mimicked the response in the cell phenotype and behavior seen in the transition from soft materials to stiff materials, including the cytoskeletal structure, expression of keratocyte phenotype markers, and cell behavior. In conclusion, this study shows that substrate stiffness regulates the cell phenotype marker expression and cell behavior of keratocytes by Rac1-mediated cytoskeletal reorganization. This knowledge contributes to the development of corneal tissue engineering.
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| 11. |
- Chen, Zhixuan, et al.
(författare)
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Effects of Zinc, Magnesium, and Iron Ions on Bone Tissue Engineering
- 2022
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 8:6, s. 2321-2335
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Forskningsöversikt (refereegranskat)abstract
- Large-sized bone defects are a great challenge in clinics and considerably impair the quality of patients' daily life. Tissue engineering strategies using cells, scaffolds, and bioactive molecules to regulate the microenvironment in bone regeneration is a promising approach. Zinc, magnesium, and iron ions are natural elements in bone tissue and participate in many physiological processes of bone metabolism and therefore have great potential for bone tissue engineering and regeneration. In this review, we performed a systematic analysis on the effects of zinc, magnesium, and iron ions in bone tissue engineering. We focus on the role of these ions in properties of scaffolds (mechanical strength, degradation, osteogenesis, antibacterial properties, etc.). We hope that our summary of the current research achievements and our notifications of potential strategies to improve the effects of zinc, magnesium, and iron ions in scaffolds for bone repair and regeneration will find new inspiration and breakthroughs to inspire future research.
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| 12. |
- Chouhan, Dimple, et al.
(författare)
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Silkworm Silk Matrices Coated with Functionalized Spider Silk Accelerate Healing of Diabetic Wounds
- 2019
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:7, s. 3537-3548
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Tidskriftsartikel (refereegranskat)abstract
- Complex cutaneous wounds like diabetic foot ulcers represent a critical clinical challenge and demand a large-scale and low-cost strategy for effective treatment. Herein, we use a rabbit animal model to investigate efficacy of bioactive wound dressings made up of silk biomaterials. Nanofibrous mats of Antheraea assama silkworm silk fibroin (AaSF) are coated with various recombinant spider silk fusion proteins through silk-silk interactions to fabricate multifunctional wound dressings. Two different types of spider silk coatings are used to compare their healing efficiency: FN-4RepCT (contains a cell binding motif derived from fibronectin) and Lac-4RepCT (contains a cationic antimicrobial peptide from lactoferricin). AaSF mats coated with spider silk show accelerated wound healing properties in comparison to the uncoated mats. Among the spider silk coated variants, dual coating of FN-4RepCT and Lac-4RepCT on top of AaSF mat demonstrated better wound healing efficiency, followed by FN-4RepCT and Lac-4RepCT single coated counterparts. The in vivo study also reveals excellent skin regeneration by the functionalized silk dressings in comparison to commercially used Duoderm dressing and untreated wounds. The spider silk coatings demonstrate early granulation tissue development, re-epithelialization, and efficient matrix remodelling of wounds. The results thus validate potential of bioactive silk matrices in faster repair of diabetic wounds.
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| 13. |
- Chouhan, Dimple, et al.
(författare)
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Silkworm Silk Scaffolds Functionalized with Recombinant Spider Silk Containing a Fibronectin Motif Promotes Healing of Full-Thickness Burn Wounds
- 2019
-
Ingår i: ACS Biomaterials Science & Engineering. - : AMER CHEMICAL SOC. - 2373-9878. ; 5:9, s. 4634-4645
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Tidskriftsartikel (refereegranskat)abstract
- Full-thickness cutaneous wounds, such as deep burns, are complex wounds that often require surgical interventions. Herein, we show the efficacy of acellular grafts that can be made available off-the-shelf at an affordable cost using silk biomaterials. Silkworm silk fibroin (SF), being a cost-effective and natural biopolymer, provides essential features required for the fabrication of three-dimensional constructs for wound-healing applications. We report the treatment of third-degree burn wounds using a freeze-dried microporous scaffold of Antheraea assama SF (AaSF) functionalized with a recombinant spider silk fusion protein FN-4RepCT (FN-4RC) that holds the fibronectin cell binding motif. In order to examine the healing efficiency of functionalized silk scaffolds, an in vivo burn rat model was used, and the scaffolds were implanted by a one-step grafting procedure. The aim of our work is to investigate the efficacy of the developed acellular silk grafts for treating full-thickness wounds as well as to examine the effect of recombinant spider silk coatings on the healing outcomes. Following 14-day treatment, AaSF scaffolds coated with FN-4RC demonstrated accelerated wound healing when compared to the uncoated counterpart, commercially used DuoDERM dressing patch, and untreated wounds. Histological assessments of wounds over time further confirmed that functionalized silk scaffolds promoted wound healing, showing vascularization and re-epithelialization in the initial phase. In addition, higher extent of tissue remodeling was affirmed by the gene expression study of collagen type I and type III, indicating advanced stage of healing by the silk treatments. Thus, the present study validates the potential of scaffolds of combined silkworm silk and FN-4RC for skin regeneration.
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| 14. |
- Fuchs, Stefanie, et al.
(författare)
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In-Line Analysis of Organ-on-Chip Systems with Sensors : Integration, Fabrication, Challenges, and Potential
- 2021
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 7:7, s. 2926-2948
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Forskningsöversikt (refereegranskat)abstract
- Organ-on-chip systems are promising new in vitro research tools in medical, pharmaceutical, and biological research. Their main benefit, compared to standard cell culture platforms, lies in the improved in vivo resemblance of the cell culture environment. A critical aspect of these systems is the ability to monitor both the cell culture conditions and biological responses of the cultured cells, such as proliferation and differentiation rates, release of signaling molecules, and metabolic activity. Today, this is mostly done using microscopy techniques and off-chip analytical techniques and assays. Integrating in situ analysis methods on-chip enables improved time resolution, continuous measurements, and a faster read-out; hence, more information can be obtained from the developed organ and disease models. Integrated electrical, electrochemical, and optical sensors have been developed and used for chemical analysis in lab-on-a-chip systems for many years, and recently some of these sensing principles have started to find use in organ-on-chip systems as well. This perspective review describes the basic sensing principles, sensor fabrication, and sensor integration in organ-on-chip systems. The review also presents the current state of the art of integrated sensors and discusses future potential. We bring a technological perspective, with the aim of introducing in-line sensing and its promise to advance organ-on-chip systems and the challenges that lie in the integration to researchers without expertise in sensor technology.
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| 15. |
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| 16. |
- Güler, Rezan, et al.
(författare)
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VEGFR2-Specific Ligands Based on Affibody Molecules Demonstrate Agonistic Effects when Tetrameric in the Soluble Form or Immobilized via Spider Silk
- 2019
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:12, s. 6474-6484
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Tidskriftsartikel (refereegranskat)abstract
- Strategies to promote vascularization are being developed in order to improve long-term survival of artificial tissue constructs. Vascular endothelial growth factor A (VEGFA) has an important role in both pathological and physiological angiogenesis, mediated by binding to VEGF receptors (VEGFRs). In nature, signaling can be modulated by presentation of growth factors in either soluble form or bound to the extracellular matrix. Herein, a previously reported VEGFR2-binding antagonistic affibody heterodimer (di-Z(VEGFR2)) was formatted into a tetrameric construct (tetra-Z(VEGFR2)) with the intention of generating artificial agonistic ligands for VEGFR2 signaling. In vitro cell assays demonstrated that tetra-Z(VEGFR2) induced VEGFR2 phosphorylation and increased cell proliferation, in contrast to di-Z(VEGFR2). In order to simulate matrix-bound factors, both constructs were fused at the genetic level to a partial spider silk protein, 4RepCT. Assembly of the silk fusion proteins onto a solid surface was verified by quartz crystal microbalance with dissipation analysis. Moreover, surface plasmon resonance studies demonstrated retained VEGFR2 binding ability of di-Z(VEGFR2) silk and tetra-Z(VEGFR2)-silk after silk-mediated immobilization. Cell culture studies demonstrated that VEGFR2-overexpressing cells adhered to di-Z(VEGFR2) -silk and tetra-Z(VEGFR2) -silk and had activated VEGFR2 signaling. Altogether, we demonstrate the potential of especially tetra-Z(VEGFR2)-silk to promote angiogenesis in tissue-engineering applications. The results from the study also show that molecules can obtain completely new functions when presented on materials, and verifying the biological effects after functionalizing materials is thus always recommended.
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| 17. |
- Hedberg, Yolanda S., et al.
(författare)
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Can Cobalt(II) and Chromium(III) ions released from joint prostheses influence the friction coefficient?
- 2015
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Ingår i: ACS Biomaterial Science and Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 1:8, s. 617-620
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Tidskriftsartikel (refereegranskat)abstract
- Cobalt chromium molybdenum alloys (CoCrMo) are commonly used as articulating components in joint prostheses. In this tribocorrosive environment, wear debris and metal ionic species are released and interact with proteins, possibly resulting in protein aggregation. This study aimed to investigate whether this could have an effect on the friction coefficient in a typical material couple, namely CoCrMo-on-polyethylene. It was confirmed that both Co(II) and Cr(III) ions, and their combination, at concentrations relevant for the metal release situation, resulted in protein aggregation and its concomitant precipitation, which increased the friction coefficient. Future studies should identify the clinical importance of these findings.
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| 18. |
- Hulander, Mats, 1974, et al.
(författare)
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Influence of Fibrinogen on Staphylococcus epidermidis Adhesion Can Be Reversed by Tuning Surface Nanotopography
- 2019
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Ingår i: ACS Biomaterial Science and Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:9, s. 4323-4330
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Tidskriftsartikel (refereegranskat)abstract
- Surface modifications in the nanoscale regime have shown promising potential in the combat against bacterial adhesion and colonization of surfaces. However, detailed knowledge of how the bacteria-substrate interactions occur is still limited. Herein we have used a gradient in nanostructure density on a surface, realized by immobilizing 40 nm sized silicon dioxide nanoparticles with increasing distance on a glass surface, to systematically study the initial attachment of Staphylococcus epidermidis with or without the presence of human fibrinogen. By using a parallel plate laminar flow chamber, we found a near-linear positive correlation between the adhesion of S. epidermidis with increasing nanoparticle density on unmodified (hydrophilic) nanogradients as well as on gradients where polyethylene glycol was immobilized on the surface in-between nanoparticles. However, if the nanostructured gradient was precoated with human fibrinogen the opposite relationship was observed, although the adsorbed amount of fibrinogen was found to be higher on nanostructured than on smooth surfaces. Our results highlight that even minute changes of the nanotopography on a surface can have profound impact on initial attachment of S. epidermidis to biomaterial surfaces and that the presence of nanostructures strongly hampered the cell's ability to bind to adsorbed fibrinogen, possibly due to changes in the orientation or secondary structure of the fibrinogen molecule upon adsorption.
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| 19. |
- Johansson, Ulrika, 1974-, et al.
(författare)
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Integration of Primary Endocrine Cells and Supportive Cells Using Functionalized Silk Promotes the Formation of Prevascularized Islet-like Clusters
- 2020
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 6:2, s. 1186-1195
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Tidskriftsartikel (refereegranskat)abstract
- Pancreatic islet transplantation has not yet succeeded as an overall treatment for type 1 diabetes because of limited access to donor islets, as well as low efficacy and poor reproducibility of the current procedure. Herein, a method to create islets-like composite clusters (coclusters) from dispersed endocrine cells and supportive cells is described, attempting to improve compatibility with the recipient and more efficiently make use of the donor-derived material. To mimic the extracellular matrix environment, recombinant,spider silk functionalized with cell binding motifs are used as 3D support for the coclusters. A cell binding motif derived from fibronectin (FN) was found superior in promoting cell adherence, while a plain RGD-motif incorporated in the repetitive part of the silk protein (2R) increased the mobility and cluster formation of endocrine cells. Self-assembly of a mixture of FN/2R silk is utilized to integrate endocrine cells together with endothelial and mesenchymal cells into islet-like coclusters. Both xenogenic and allogenic versions of these coclusters were found to be viable and were able to respond to dynamic glucose stimulation with insulin release. Moreover, the endothelial cells were found to be colocalized with the endocrine cells, showing that the silk combined with supportive cells may promote vascularization. This method to engineer combined islet-like coclusters allows donor-derived endocrine cells to be surrounded by supportive cells from the recipient, which have the potential to further promote engraftment in the host and considerably reduce risk of rejection.
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| 20. |
- Karazisis, Dimitrios, 1977, et al.
(författare)
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Molecular Response to Nanopatterned Implants in the Human Jaw Bone
- 2021
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Ingår i: Acs Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 7:12, s. 5878-5889
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Tidskriftsartikel (refereegranskat)abstract
- Implant surface modification by nanopatterning is an interesting route for enhancing osseointegration in humans. Herein, the molecular response to an intentional, controlled nanotopography pattern superimposed on screw-shaped titanium implants is investigated in human bone. When clinical implants are installed, additional two mini-implants, one with a machined surface (M) and one with a machined surface superimposed with a hemispherical nanopattern (MN), are installed in the posterior maxilla. In the second-stage surgery, after 6-8 weeks, the mini-implants are retrieved by unscrewing, and the implant-adherent cells are subjected to gene expression analysis using quantitative polymerase chain reaction (qPCR). Compared to those adherent to the machined (M) implants, the cells adherent to the nanopatterned (MN) implants demonstrate significant upregulation (1.8- to 2-fold) of bone-related genes (RUNX2, ALP, and OC). No significant differences are observed in the expression of the analyzed inflammatory and remodeling genes. Correlation analysis reveals that older patient age is associated with increased expression of proinflammatory cytokines (TNF-alpha and MCP-1) on the machined implants and decreased expression of proosteogenic factor (BMP-2) on the nanopatterned implants. Controlled nanotopography, in the form of hemispherical 60 nm protrusions, promotes gene expressions related to early osteogenic differentiation and osteoblastic activity in implant-adherent cells in the human jaw bone.
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| 21. |
- Kurut, Anil, et al.
(författare)
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Dimerization of Terminal Domains in Spiders Silk Proteins Is Controlled by Electrostatic Anisotropy and Modulated by Hydrophobic Patches
- 2015
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 1:6, s. 363-371
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Tidskriftsartikel (refereegranskat)abstract
- The well-tuned spinning technology from spiders has attracted many researchers with the promise of producing high-performance, biocompatible, and yet biodegradable fibers. So far, the intricate chemistry and rheology of spinning have eluded us. A breakthrough was achieved recently, when the 3D structures of the N and C terminal domains of spider dragline silk were resolved and their pH-induced dimerization was revealed. To understand the terminal domains' dimerization mechanisms, we developed a protein model based on the experimental structures that reproduces charge and hydrophobic anisotropy of the complex protein surfaces. Monte Carlo simulations were used to study the thermodynamic dimerization of the N-terminal domain as a function of pH and ionic strength. We show that the hydrophobic and electrostatic anisotropies of the N-terminal domain cooperate constructively in the association process. The dipolar attractions at pH 6 lead to weakly bound dimers by forcing an antiparallel monomer orientation, stabilized by hydrophobic locking at close separations. Elevated salt concentrations reduce the thermodynamic dimerization constant due to screened electrostatic dipolar attraction. Moreover, the mutations on ionizable residues reveal a free energy of binding, proportional to the dipole moment of the mutants. It has previously been shown that dimers, formed at pH 6, completely dissociate at pH 7, which is thought to be due to altered protein charges. In contrast, our study indicates that the pH increase has no influence on the charge distribution of the N-terminal domain. Instead, the pH-induced dissociation is due to an adapted, loose conformation at pH 7, which significantly hampers both electrostatic and hydrophobic attractive interactions.
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| 22. |
- Leblanc, K. J., et al.
(författare)
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Stability of High Speed 3D Printing in Liquid-Like Solids
- 2016
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society. - 2373-9878. ; 2:10, s. 1796-1799
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Tidskriftsartikel (refereegranskat)abstract
- Fluid instabilities limit the ability of features to hold their shape in many types of 3D printing as liquid inks solidify into written structures. By 3D printing directly into a continuum of jammed granular microgels, these instabilities are circumvented by eliminating surface tension and body forces. However, this type of 3D printing process is potentially limited by inertial instabilities if performed at high speeds where turbulence may destroy features as they are written. Here, we design and test a high-speed 3D printing experimental system to identify the instabilities that arise when an injection nozzle translates at 1 m/s. We find that the viscosity of the injected material can control the Reynold's instability, and we discover an additional, unanticipated instability near the top surface of the granular microgel medium.
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| 23. |
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| 24. |
- Liang, Lijun, et al.
(författare)
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Theoretical Evaluation on Potential Cytotoxicity of Graphene Quantum Dots
- 2016
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Ingår i: ACS Biomaterials Science & Engineering. - : AMER CHEMICAL SOC. - 2373-9878. ; 2:11, s. 1983-1991
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Tidskriftsartikel (refereegranskat)abstract
- Owing to unique morphology, ultrasmall lateral sizes, and exceptional properties, graphene quantum dots (GQDs) hold great potential in many applications, especially in the field of electrochemical biosensors, bioimaging, drug delivery, et cetera. Its biosafety and potential cytotoxicity to human and animal cells has been a growing concern in recent years. In this work, the potential cytotoxicity of GQDs was evaluated by molecular dynamics simulations. Our simulation demonstrates that small size GQDs could easily permeate into the lipid membrane in a vertical way. It is relatively difficult to permeate into the lipid membrane for GQDs that are larger than GQD61 on the nanosecond time-scale. The thickness of the POPC membrane could even be affected by the small size of GQDs. Free energy calculations revealed that the free energy barrier of GQD permeation through the lipid membrane could greatly change with the change of GQD size. Under high GQD concentration, the GQD molecules could rapidly aggregate in water but disaggregate after entering into the membrane interior. Moreover, high concentrations of GQDs could induce changes in the structure properties and diffusion properties of the lipid bilayer, and it may affect the cell signal transduction. However, GQDs with relatively small size are not large enough to mechanically damage the lipid membrane. Our results suggest that the cytotoxicity of GQDs with small size is low and may be appropriate for biomedical application.
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| 25. |
- Lu, Yung Hsiang, et al.
(författare)
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Temporally Controlled Photouncaged Epidermal Growth Factor Influences Cell Fate in Hydrogels
- 2022
-
Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 8:1, s. 185-195
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Tidskriftsartikel (refereegranskat)abstract
- Hydrogels are powerful materials that more accurately mimic the cellular microenvironment over static two-dimensional culture. Photochemical strategies enable dynamic complexity to be achieved within hydrogels to better mimic the extracellular matrix; however, many photochemical systems to pattern proteins within hydrogels are complicated by long reaction times to immobilize these proteins wherein the protein can lose activity. As proof-of-concept, we demonstrate an elegant method where photocaged proteins are immobilized in hydrogels and then directly photoactivated. Specifically, we immobilized streptavidin-ortho-nitrobenzyl-modified epidermal growth factor (EGF) to cross-linked hyaluronan hydrogels and cultured two EGF-responsive cancer cells of breast and lung therein. We used light to temporally uncage and control EGF activation, thereby inducing cell death in breast cancer cells and proliferation in lung cancer cells. These results show how temporal, photochemical, protein activation influences cellular response and lays the foundation for further advances in manipulating the in vitro environment to control cell fate.
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| 26. |
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| 27. |
- Panagiotis Tasiopoulos, Christos, et al.
(författare)
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Fibrillar Nanomembranes of Recombinant Spider Silk Protein Support Cell Co-culture in an In Vitro Blood Vessel Wall Model
- 2021
-
Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 7:7, s. 3332-3339
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Tidskriftsartikel (refereegranskat)abstract
- Basement membrane is a thin but dense network of self-assembled extracellular matrix (ECM) protein fibrils that anchors and physically separates epithelial/endothelial cells from the underlying connective tissue. Current replicas of the basement membrane utilize either synthetic or biological polymers but have not yet recapitulated its geometric and functional complexity highly enough to yield representative in vitro co-culture tissue models. In an attempt to model the vessel wall, we seeded endothelial and smooth muscle cells on either side of 470 +/- 110 nm thin, mechanically robust, and nanofibrillar membranes of recombinant spider silk protein. On the apical side, a confluent endothelium formed within 4 days, with the ability to regulate the permeation of representative molecules (3 and 10 kDa dextran and IgG). On the basolateral side, smooth muscle cells produced a thicker ECM with enhanced barrier properties compared to conventional tissue culture inserts. The membranes withstood 520 +/- 80 Pa pressure difference, which is of the same magnitude as capillary blood pressure in vivo. This use of protein nanomembranes with relevant properties for co-culture opens up for developing advanced in vitro tissue models for drug screening and potent substrates in organ-on-a-chip systems.
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| 28. |
- Peña Fernández, Marta
(författare)
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Full-field strain analysis of bone-biomaterial systems produced by osteoregenerative biomaterials after in vivo service in an ovine model
- 2019
-
Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 5:5, s. 2543-2554
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Tidskriftsartikel (refereegranskat)abstract
- Osteoregenerative biomaterials for the treatment of bone defects are under much development, with the aim of favoring osteointegration up to complete bone regeneration. A detailed investigation of bone-biomaterial integration is vital to understand and predict the ability of such materials to promote bone formation, preventing further bone damage and supporting load-bearing regions. This study aims to characterize the ex vivo micromechanics and microdamage evolution of bone-biomaterial systems at the tissue level, combining high-resolution synchrotron micro-computed tomography, in situ mechanics and digital volume correlation. Results showed that the main microfailure events were localized close to or within the newly formed bone tissue, in proximity to the bone-biomaterial interface. The apparent nominal compressive load applied to the composite structures resulted in a complex loading scenario, mainly due to the higher heterogeneity but also to the different biomaterial degradation mechanisms. The full-field strain distribution allowed characterization of microdamage initiation and progression. The findings reported in this study provide a deeper insight into bone-biomaterial integration and micromechanics in relation to the osteoregeneration achieved in vivo for a variety of biomaterials. This could ultimately be used to improve bone tissue regeneration strategies.
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| 29. |
- Pettersson, Maria, et al.
(författare)
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Morphology and dissolution rate of wear debris from silicon nitride coatings
- 2016
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 2:6, s. 998-1004
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Tidskriftsartikel (refereegranskat)abstract
- Silicon nitride (SiNx) coatings have recentlY been introduced as a potential material for joint implant bearing surfaces, but there is no data on wear debri morphology nor their dissolution rate, something that could play a central role to implant longevity. In this study, wear debris was generated in a ball-on-disc setup in simulated body fluid. After serum digestion the debris was analyzed with scanning electron microscopy and energy-dispersive X-ray spectroscopy. The particle dissolution rate was evaluated using inductively coupled plasma techniques, on model SiNx particlEs. The wear debris from SiNx coatings was found to be round, in the nm range and formed agglomerates in the submicrometer to micrometer range. Model particles dissolved in simulated body fluid at a rate of: c(t) = 39.45[1 - exp(-1.11 X 10(-6) t], where [c(t)] = mg/L and [t] = s. This study can be used as a preliminary prediction of size, shape, and dissolution rate of wear debris from SiNx coatings.
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| 30. |
- Pupkaite, Justina, et al.
(författare)
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Delivering More of an Injectable Human Recombinant Collagen III Hydrogel Does Not Improve Its Therapeutic Efficacy for Treating Myocardial Infarction
- 2020
-
Ingår i: ACS Biomaterials Science & Engineering. - : AMER CHEMICAL SOC. - 2373-9878. ; 6:7, s. 4256-4265
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Tidskriftsartikel (refereegranskat)abstract
- Injectable hydrogels are a promising method to enhance repair in the heart after myocardial infarction (MI). However, few studies have compared different strategies for the application of biomaterial treatments. In this study, we use a clinically relevant mouse MI model to assess the therapeutic efficacy of different treatment protocols for intramyocardial injection of a recombinant human collagen III (rHCIII) thermoresponsive hydrogel. Comparing a single hydrogel injection at an early time point (3 h) versus injections at multiple time points (3 h, 1 week, and 2 weeks) post-MI revealed that the single injection group led to superior cardiac function, reduced scar size and inflammation, and increased vascularization. Omitting the 3 h time point and delivering the hydrogel at 1 and 2 weeks post-MI led to poorer cardiac function. The positive effects of the single time point injection (3 h) on scar size and vascular density were lost when the hydrogels collagen concentration was increased from 1% to 2%, and it did not confer any additional functional improvement. This study shows that early treatment with a rHCIII hydrogel can improve cardiac function post-MI but that injecting more rHCIII (by increased concentration or more over time) can reduce its efficacy, thus highlighting the importance of investigating optimal treatment strategies of biomaterial therapy for MI.
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| 31. |
- Quellmalz, Arne, et al.
(författare)
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Citric acid cross-linked nanocellulose-based paper for size-exclusion nanofiltration
- 2015
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 1:4, s. 271-276
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Tidskriftsartikel (refereegranskat)abstract
- This article explores the effect of cross-linking of nanocellulose with citric acid for the development of novel paper filters for potential application within nanofiltration, including sterile (virus) filtration. Cladophora cellulose paper sheets were cross-linked by first soaking in 16 wt % citric acid in the presence of 1 wt % sodium hypophosphate overnight and then curing at 160 degrees C for 10 min in a hot-press. The cross-linked paper filter samples were then characterized with FTIR, AFM, N-2 gas adsorption, and tensile strength analysis (dry and wet strength). The particle retention properties were further studied with respect to filtering of 20 nm Au nanoparticles with SEM and comparing the UV absorbance intensity of the starting solution and the filtrate. The wet strength of the paper filter was greatly improved following the cross-linking, although in the dry state, the paper becomes brittle. The improved wet strength of the paper filter enables increasing the pressure gradient applied for filtration without compromising the integrity of the filter. This is the first report in which a fully nature-derived paper filter is capable of removing tracer particles as small as 20 nm. It is concluded that citric acid cross-linking of nanocellulose is beneficial for developing paper based sterile (virus) removal industrial filters.
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| 32. |
- Raina, Deepak Bushan, et al.
(författare)
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Synthesis and Characterization of a Biocomposite Bone Bandage for Controlled Delivery of Bone-Active Drugs in Fracture Nonunions
- 2020
-
Ingår i: ACS Biomaterials Science and Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 6:5, s. 2867-2878
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Tidskriftsartikel (refereegranskat)abstract
- Fracture nonunions are common in orthopedics and their treatment often involves multiple surgical interventions. The aim of this study was to fabricate and characterize a gelatin-nano-hydroxyapatite membrane (GM)-based bone bandage for controlled delivery of bio-active molecules; recombinant human bone morphogenic protein-2 (rhBMP-2) and zoledronic acid (ZA) to promote osteoinduction and prevent callus resorption, respectively. In vitro cell-material interaction experiments using MC3T3 cells seeded on the GM indicated good biocompatibility. rhBMP-2-functionalized GM promoted osteogenic differentiation of MC3T3 cells and the rhBMP-2 bio-activity thus remained, as indicated by increased levels of alkaline phosphatase compared to only GM. The GM released a small amount (1.1%) of rhBMP-2 in vitro over a period of 5 weeks, demonstrating a strong interaction of rhBMP-2 with the GM. In the first animal study, the GM specimens loaded with rhBMP-2 or with the combination of rhBMP-2 + ZA were placed in the abdominal muscle pouch of rats. In the GM + rhBMP-2 + ZA group, significantly higher bone volume (21.5 ± 5.9 vs 2.7 ± 1.0 mm3) and area (3.3 ± 2.3 vs 1.0 ± 0.4 mm2) of bone were observed compared to GM + rhBMP-2 after 4 weeks, as indicated by micro-computed tomography and histomorphometry, respectively. Finally, a nonunion model in rats was used to evaluate the efficacy of the GM bandage and bio-active molecules in healing of fracture nonunions. The GM functionalized with rhBMP-2 + ZA led to higher bone formation around the fracture (63.9 ± 19.0 vs 31.8 ± 3.7 mm3) and stronger fracture callus (110.8 ± 46.8 vs 45.6 ± 17.8 N) compared to the empty controls. However, the overall union rate was only marginally improved. The GM alone or combined with ZA did not aid in bone healing in this model. Thus, this study shows that controlled delivery of rhBMP-2 + ZA via the developed GM is a promising approach that could aid in earlier full load bearing in patients with nonunion.
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| 33. |
- Rogal, J, et al.
(författare)
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Developer's Guide to an Organ-on-Chip Model
- 2022
-
Ingår i: ACS biomaterials science & engineering. - : American Chemical Society (ACS). - 2373-9878. ; 8:11, s. 4643-4647
-
Tidskriftsartikel (refereegranskat)
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| 34. |
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| 35. |
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| 36. |
- Thatikonda, Naresh, et al.
(författare)
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Bioactivation of Spider Silk with Basic Fibroblast Growth Factor for in Vitro Cell Culture : A Step toward Creation of Artificial ECM
- 2018
-
Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 4:9, s. 3384-3396
-
Tidskriftsartikel (refereegranskat)abstract
- Presentation of immobilized growth factors with retained bioactivity remains a challenge in the field of tissue engineering. In the present study, we propose a strategy to covalently conjugate a pleiotropic growth factor, basic fibroblast growth factor (bFGF) to a partial spider silk protein at gene level. The resulting silk-bFGF fusion protein has the propensity to self-assemble into silk-like fibers, and also surface coatings, as confirmed by quartz crystal microbalance studies. Functionality of the silk-bFGF coating to bind its cognate receptor was confirmed with surface plasmon resonance studies. As a step toward the creation of an artificial ECM, the silk-bFGF protein was mixed with FN-silk, an engineered spider silk protein with enhanced cell adhesive properties. Bioactivity of the thereby obtained combined silk was confirmed by successful culture of primary human endothelial cells on coatings and integrated within fibers, even in culture medium without supplemented growth factors. Together, these findings show that silk materials bioactivated with growth factors can be used for in vitro cell culture studies, and have potential as a tissue engineering scaffold.
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| 37. |
- Theobald, J., et al.
(författare)
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Liver-Kidney-on-Chip To Study Toxicity of Drug Metabolites
- 2018
-
Ingår i: Acs Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 4:1, s. 78-89
-
Tidskriftsartikel (refereegranskat)abstract
- Advances in organ-on-chip technologies for the application in in vitro drug development provide an attractive alternative approach to replace ethically controversial animal testing and to establish a basis for accelerated drug development. In recent years, various chip-based tissue culture systems have been developed, which are mostly optimized for cultivation of one single cell type or organoid structure and lack the representation of multi organ interactions. Here we present an optimized microfluidic chip design consisting of interconnected compartments, which provides the possibility to mimic the exchange between different organ specific cell types and enables to study interdependent cellular responses between organs and demonstrate that such tandem system can greatly improve the reproducibility and efficiency of toxicity studies. In a simplified liver-kidney-on-chip model, we showed that hepatic cells that grow in microfluidic conditions abundantly and stably expressed metabolism-related biomarkers. Moreover, we applied this system for investigating the biotransformation and toxicity of Aflatoxin B1 (AFB1) and Benzoalphapyrene (BaP), as well as the interaction with other chemicals. The results clearly demonstrate that the toxicity and metabolic response to drugs can be evaluated in a flow-dependent manner within our system, supporting the importance of advanced interconnected multiorgans in microfluidic devices for application in in vitro toxicity testing and as optimized tissue culture systems for in vitro drug screening.
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| 38. |
- Tummala, Gopi Krishna, 1986-, et al.
(författare)
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Hyperelastic Nanocellulose-Reinforced Hydrogel of High Water Content for Ophthalmic Applications
- 2016
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 2:11, s. 2072-2079
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Tidskriftsartikel (refereegranskat)abstract
- A nanocellulose-reinforced poly(vinyl alcohol) hydrogel material of exceptionally high water content for ophthalmic applications is presented (>90 wt %), which also features a hitherto unprecedented combination of optical, mechanical, viscoelastic, oxygen permeability, and biocompatibility properties. The hydrogel combines the desired softness with remarkable strain-dependent mechanical strength and thereby demonstrates hyperelastic, rubber-like mechanical properties. The observed unusual mechanical behavior is due to both high water content and the combination of relatively stiff cellulose nanowhiskers entangled in a soft polymer matrix of poly(vinyl alcohol) (PVA), thus mimicking the structural characteristics of the cornea's main constituents, i.e., water and collagen.
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| 39. |
- Wang, Hui, et al.
(författare)
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Two-Photon Active Organotin(IV) Carboxylate Complexes for Visualization of Anticancer Action
- 2017
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Ingår i: ACS Biomaterials Science & Engineering. - : AMER CHEMICAL SOC. - 2373-9878. ; 3:5, s. 836-842
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Tidskriftsartikel (refereegranskat)abstract
- It is still a challenge that organotin(IV) carboxylate complexes with high-performance two-photon activity for cancer therapy. At present work, two novel organotin carboxylate complexes LSn1 and LSn2, containing coumarin moiety, were rationally designed for two-photon fluorescent imaging and anticancer purpose. The complexes possessed large two-photon action cross-sections and high quantum yields. Living cells evaluation revealed that complexes LSn1 and LSn2 exhibited good biocompatibility and deep tissue penetration over femtosecond laser with wavelength of 840 nm. Furthermore, the antitumor active and as well as possible mechanism of complexes LSn1 and LSn2 have been investigated systematically. The results indicated that complexes LSn1 and LSn2 could induce apoptotic cell death through a mitochondria] dysfunction and ROS elevation pathway. The present work provides a strategy for rationally designing organotin(IV) carboxylate complexes with two-photon activity and antitumor activity.
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| 40. |
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| 41. |
- Xia, Wei, et al.
(författare)
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Bioactive Spheres: The Way of Treating Dentin Hypersensitivity
- 2016
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Ingår i: Acs Biomaterials-Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 2:5, s. 734-740
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Tidskriftsartikel (refereegranskat)abstract
- Sealing exposed dental tubules is the most effective and long-term way to relieve the pain induced by dental sensitivity. A bioactive hollow sphere (strontium substituted calcium phosphate) was synthesized and added in toothpaste to study its effect on dental hypersensitivity via tooth tubules occlusion and mineralization. The size of spheres is perfect for penetrating into dental tubules, reaching to 20 pm into the tubules. The exposed dental tubules were occluded by spheres and new apatite layer after 3 days brushing. The spheres attached to the surface of dentin and the mineralized surface contained two layers, a porous layer followed by a dense apatite layer. The porous layer can be dissolved in an acidic solution, but the following dense layer could be kept even after soaking in an acid solution. In conclusion, Sr-substituted calcium phosphate spheres could be a good candidate for at-home treatment of dental hypersensitivity.
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| 42. |
- Zhou, Juan, et al.
(författare)
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Trehalose-Conjugated, Photofunctionalized Mesoporous Silica Nanoparticles for Efficient Delivery of Isoniazid into Mycobacteria
- 2015
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Ingår i: ACS Biomaterials Science & Engineering. - : American Chemical Society (ACS). - 2373-9878. ; 1:12, s. 1250-1255
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Tidskriftsartikel (refereegranskat)abstract
- Glyconanoparticle carriers have been synthesized and efficiently delivered into mycobacteria. Mesoporous silica nanoparticles were functionalized with a,a-trehalose through azide-mediated surface photoligation, and loaded with the antitubercular drug isoniazid. The glyconanoparticles showed high isoniazid loading capacity and higher antimicrobial activity than the free drug.
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