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(a) Stability of gelatin hydrogel deposited on top of a titanium disk incubated in PBS buffer solution at 37 °C after 5 days of experiment. (b) Surface aspect of a titanium disk after the deposition of oxidized (L-DOPA-L-lysine)2-L-DOPA for 1 h. (c) Stability of gelatin hydrogel deposited on top of a titanium disk modified with oxidized (L-DOPA-L-lysine)2-L-DOPA incubated in PBS buffer solution at 37 °C after 21 days of experiment. To visualize the hydrogel on the surface of a titanium disc, the gelatin hydrogel has been labeled with a red dye (Sirius red). (d) Metabolic activity as measured by a fluorescence viability kit (Resazurin) of 3T3 cells encapsulated in gelatin hydrogel in direct contact with titanium-oxidized (L-DOPA-L-lysine)2-L-DOPA versus a control (no titanium in contact with cells encapsulated in gelatin hydrogel), where I.F = intensity of fluorescence. Statistics were performed using a Mann–Whitney test (*p < 0.05).
Source publication
For in-dwelling implants, controlling the biological interface is a crucial parameter to promote tissue regeneration and prevent implant failure. For this purpose, one possibility is to facilitate the establishment of the interface with cell-laden hydrogel fixed to the implant. However, for proper functioning, the stability of the hydrogel on the i...
Citations
... This morphological behaviour of the HMF is recurrent in membranes with larger pore sizes (1800-4800 nm 2 according to the mean represented in Fig. 3a and b), this could suggest cell penetration and migration within the scaffold itself [54]. 8%/4% PCL/Ge revealed some background fluorescence that can be attributed to the non-specific phalloidin binding to high concentrations of amino acids derived from the gelatin that is also found in the composition of actin filaments [55,56]. Even though, there is a noteworthy decrease in the overall HMF cluster area size (Fig. 10) when comparing Matrigel™ (result mean of 116,436 µm 2 ) to PU (result mean of 28,576 µm 2 ) and PVA (mean area of 11,806 µm 2 ). ...
In recent years the interest in synthetic scaffolds has increased significantly as an alternative to animal-derived materials, as well as the advancement of material and manufacturing engineering, has resulted in improved standardisation and reproducibility within the field. Despite these advancements, a significant amount of research on animal-derived scaffolds, whilst research on synthetic materials is lacking for the growth of non-tumourgenic breast cell lines. The main objective of this work is to manufacture biodegradable scaffolds using biocompatible materials such as PVA (Polyvinyl Alcohol), PU (Polyurethane), Ge (Gelatin) and PCL (Poly-(-caprolactone) to test human cell adhesion and investigate the optimal system that supports representative tissue organisation and that could be used as an alternative to Matrigel™. Here, human mammary fibroblasts (HMF) were used as proof of concept. The membranes were manufactured using the process of electrospinning and characterised by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (ATR-FTIR), contact angle, tensile strength, and degradation studies. The assessment of the membranes as a viable biomaterial for the growth and development of cells was studied by MTT proliferation assay, fluorescence microscopy and SEM imaging. Results demonstrate that all materials are suitable for HMF proliferation. However, from microscopy analysis, only PU and PVA membranes induced morphological organisation of HMF similar to those results obtained in the Matrigel™ control conditions. This feasibility study reveals that HMF organisation, and proliferation are affected by the properties of the scaffold. Consequently, scaffolds parameters should be adjusted and manipulated to impact cell behaviour and emulate in vivo conditions.
... hydrogels (Solorio et al., 2015;Subramaniam et al., 2016;Murahashi et al., 2019;Wang et al., 2019). However, these materials either serve as structural support or provide cell adhesive motif during bone healing (Sarker et al., 2015;Barthes et al., 2017). Very few materials offer more complex biological functions which allow efficient regulation of multiple biological processes during tissue regeneration. ...
Exploration for ideal bone regeneration materials still remains a hot research topic due to the unmet clinical challenge of large bone defect healing. Bone grafting materials have gradually evolved from single component to multiple-component composite, but their functions during bone healing still only regulate one or two biological processes. Therefore, there is an urgent need to develop novel materials with more complex composition, which convey multiple biological functions during bone regeneration. Here, we report an naturally nanostructured ECM based composite scaffold derived from fish air bladder and combined with dicalcium phosphate (DCP) microparticles to form a new type of bone grafting material. The DCP/acellular tissue matrix (DCP/ATM) scaffold demonstrated porous structure with porosity over 65% and great capability of absorbing water and other biologics. In vitro cell culture study showed that DCP/ATM scaffold could better support osteoblast proliferation and differentiation in comparison with DCP/ADC made from acid extracted fish collagen. Moreover, DCP/ATM also demonstrated more potent bone regenerative properties in a rat calvarial defect model, indicating incorporation of ECM based matrix in the scaffolds could better support bone formation. Taken together, this study demonstrates a new avenue toward the development of new type of bone regeneration biomaterial utilizing ECM as its key components.
... As both Gelatin and HA are adhesive by their nature, the establishment of the interface would not be problematic. If necessary, a layer of wet adhesive can be added as we have described previously ( Barthes et al., 2017). Another advantage of the patch system is that the MSCs can continue their differentiation with the right polarity (as the substrate defines their positioning) in a microenvironment that is particularly suitable for respiratory epithelium differentiation. ...
Here we report fabrication of Gelatin based biocomposite films and their application in developing epithelial patches. The films were loaded with an epithelial cell growth factor cocktail and used as an extracellular matrix mimic (ECM mimic) for in vitro regeneration of organised respiratory epithelium using Calu‐3 cell line and mesenchymal stem cells (MSCs). Our data show differentiation of Calu‐3 cells on composite films as evidenced by tight junction protein expression and barrier formation. The films also supported attachment, migration and proliferation of alveolar basal epithelial cell line A549. We also show the suitability of the composite films as a biomimetic scaffold and growth factor delivery platform for differentiation of human MSCs to epithelial cells. MSCs differentiation to the epithelial lineage was confirmed by staining for epithelial and stem cell specific markers. Our data show that the MSCs acquire the epithelial characteristics after two weeks with significant reduction in vimentin, increase in pan cytokeratin expression as well as morphological changes. However, despite the expression of epithelial lineage markers these cells did not form fully functional tight junctions as evidenced by low expression of junctional protein ZO1. Further optimisation of culture conditions and growth factor cocktail is required to enhance tight junction formation in MSCs derived epithelial cells on the composite hydrogels. Nevertheless, our data clearly highlight the possibility of using MSCs in epithelial tissue engineering and the applicability of the composite hydrogels as transferrable ECM mimics and delivery platforms with potential applications in regenerative medicine and in vitro modelling of barrier tissues.
... These have proven their adhesion even under wet conditions. [141][142][143][144][145] Apart from wound healing, these adhesives were also applied in other fields like dentistry, 146 facilitating implantation, 147,148 as an antifouling agents 149 etc. ...
Bioadhesives and glues are widely used as an adjunct to conventional methods employed in healing the post‐surgical injuries and restoration of normal tissue functions. Protein‐based bioadhesives have been used for a long time, and they are a more biocompatible alternative compared with synthetic adhesives. They offer advantages such as ease of application, reduction in surgery time, improved quality and strength of the seal, and effective sealing. Also, bioadhesives are being exploited in different fields like controlled and site‐specific drug delivery systems, and in tissue engineering and regeneration. There are various marketed protein‐based glues that are available in different forms. Thus, all in all, it is a patient compliant system, thereby increasing its recent popularity. This article provides insight into different types and sources of protein‐based bioadhesives, their history of use, mechanism of adhesion. and various products that have been approved by the regulatory authorities for clinical use. It also includes information regarding the products in clinical trials and potential applications.
... But the practical application of SPIAs has been limited, due to the low water resistance [4]. Chemical and physical methods were applied to enhance water resistance of the SPIAs, including denaturation [5], cross-linking agents [6], synthetic resin [7], nano-material [8] and biomimetic modification [9]. Among those modifications, the most effective way is using cross-linking agents and synthetic resins, such as phenol formaldehyde resin [10], polyisocynates [11], polyamidoamine-epichlorohydrin resin [12] and epoxide [13]. ...
The purpose of this study was to improve the performance of soy protein isolate (SPI) adhesives using a polyurethane elastomer. Triglycidylamine (TGA), SPI, thermoplastic polyurethane elastomer (TPU), and γ-(2,3-epoxypropoxy) propyltrimethoxysilane (KH-560) were used to develop a novel SPI-based adhesive. The residual rate, functional groups, thermal stability, and fracture surface micrographs of the cured adhesives were characterized. Three-ply plywood was fabricated, and the dry/wet shear strength was determined. The experimental results suggested that introducing 2% TGA improved the residual rate of the SPI/TGA adhesive by 4.1% because of the chemical cross-linking reaction between epoxy groups and protein molecules. Incorporating 7% TPU into the SPI/TGA adhesive, the residual rate of the adhesive increased by 5.2% and the dry/wet shear strength of plywood bonded by SPI/TGA/TPU adhesive increased by 10.7%/67.7%, respectively, compared with that of SPI/TGA adhesive. When using KH-560 and TPU together, the residual rate of the adhesive improved by 0.9% compared with that of SPI/TGA/TPU adhesive. The dry and wet shear strength of the plywood bonded by the SPI/TGA/TPU/KG-560 adhesive further increased by 23.2% and 23.6% respectively when compared with that of SPI/TGA/TPU adhesive. TPU physically combined with the SPI/TGA adhesive to form a interpenetration network and KH-560 acted as a bridge to connect TPU and SPI/TGA to form a joined crosslinking network, which improved the thermo stability/toughness of the adhesive and created a uniform ductile fracture section of the adhesive.
... These click chemistrybased hydrogel materials show immense potentials to be used in the latest technologies like 3D bioprinting for creating tissue and organ structures [26][27][28][29]. Even though scaffold-free approaches are investigated for tissue regeneration [30], injectable in situ hydrogels either with or without live cells, growth factors, biomolecules, nanoparticles and microspheres are promising for tissue engineering applications with improved mechanical properties and biocompatibility [31][32][33][34][35][36][37][38][39][40]. ...
Background
The tissue engineering and regenerative medicine approach require biomaterials which are biocompatible, easily reproducible in less time, biodegradable and should be able to generate complex three-dimensional (3D) structures to mimic the native tissue structures. Click chemistry offers the much-needed multifunctional hydrogel materials which are interesting biomaterials for the tissue engineering and bioprinting inks applications owing to their excellent ability to form hydrogels with printability instantly and to retain the live cells in their 3D network without losing the mechanical integrity even under swollen state.
Methods
In this review, we present the recent developments of in situ hydrogel in the field of click chemistry reported for the tissue engineering and 3D bioinks applications, by mainly covering the diverse types of click chemistry methods such as Diels–Alder reaction, strain-promoted azide-alkyne cycloaddition reactions, thiol-ene reactions, oxime reactions and other interrelated reactions, excluding enzyme-based reactions.
Results
The click chemistry-based hydrogels are formed spontaneously on mixing of reactive compounds and can encapsulate live cells with high viability for a long time. The recent works reported by combining the advantages of click chemistry and 3D bioprinting technology have shown to produce 3D tissue constructs with high resolution using biocompatible hydrogels as bioinks and in situ injectable forms.
Conclusion
Interestingly, the emergence of click chemistry reactions in bioink synthesis for 3D bioprinting have shown the massive potential of these reaction methods in creating 3D tissue constructs. However, the limitations and challenges involved in the click chemistry reactions should be analyzed and bettered to be applied to tissue engineering and 3D bioinks. The future scope of these materials is promising, including their applications in in situ 3D bioprinting for tissue or organ regeneration.
The rapid and robust adhesion of marine mussels to diverse solid surfaces in wet environments is mediated by the secreted mussel adhesive proteins which are abundant in a catecholic amino acid, L-3,4-dihydroxyphenylalanine (Dopa). Over the last two decades, enormous efforts have been devoted to the development of synthetic mussel-inspired adhesives with water-resistant adhesion and cohesion properties by modifying polymer systems with Dopa and its analogues. In the present review, an overview of the unique features of various mussel foot proteins is provided in combination with an up-to-date understanding of catechol chemistry, which contributes to the strong interfacial binding via balancing a variety of covalent and noncovalent interactions including oxidative cross-linking, electrostatic interaction, metal-catechol coordination, hydrogen bonding, hydrophobic interactions and π–π/cation-π interactions. The recent developments of novel Dopa-containing adhesives with on-demand mechanical properties and other functionalities are then summarized under four broad categories: viscous coacervated adhesives, soft adhesive hydrogels, smart adhesives, and stiff adhesive polyesters, where their emerging applications in engineering, biological and biomedical fields are discussed. Limitations of the developed adhesives are identified and future research perspectives in this field are proposed.
The advent of electrochromic aqueous batteries represents a promising trend in the development of smart and environmentally friendly energy storage devices. However, it remains a great challenge to integrate electrochromic, flexible, and patterned features into a single battery unit through a simple operation. Herein, an entirely new class of hetero‐polyacid‐based underwater adhesives is designed and synthesized by combining the redox properties of hetero‐polyacids and the water‐resistant binding of adhesives in single system. The hybrid underwater adhesives not only serve as printable electrode coatings in aqueous solution but also offer unique electrochromic feature for guiding the convenient fabrication of self‐powered electrochromic aqueous battery. The reversible discharging and H2O2 assistant charging behavior is also demonstrated. This kind of wet and electrochromic adhesive with excellent toleration of mechanical deformation offers great promise in developing flexible and smart energy storage configuration, which provides a user‐device interface platform allowing one to evaluate the battery's charging state based on the naked eye–visible change in color. Printable electrochromic adhesives are fabricated through co‐assembly of hetero‐polyacid and aromatic amino acids in water. The resultant patterned electrode coatings exhibit excellent bending and stretching tolerance in aqueous solution, thus open up new opportunities for creating flexible and smart batteries, where the discharging and charging states can be monitored by the naked eye–visible change in color.
