You are researching: Chitosan
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AUTHOR Alison, Lauriane and Menasce, Stefano and Bouville, Florian and Tervoort, Elena and Mattich, Iacopo and Ofner, Alessandro and Studart, André R.
Title 3D printing of sacrificial templates into hierarchical porous materials [Abstract]
Year 2019
Journal/Proceedings Scientific Reports
Reftype Alison2019
Hierarchical porous materials are widespread in nature and find an increasing number of applications as catalytic supports, biological scaffolds and lightweight structures. Recent advances in additive manufacturing and 3D printing technologies have enabled the digital fabrication of porous materials in the form of lattices, cellular structures and foams across multiple length scales. However, current approaches do not allow for the fast manufacturing of bulk porous materials featuring pore sizes that span broadly from macroscopic dimensions down to the nanoscale. Here, ink formulations are designed and investigated to enable 3D printing of hierarchical materials displaying porosity at the nano-, micro- and macroscales. Pores are generated upon removal of nanodroplets and microscale templates present in the initial ink. Using particles to stabilize the droplet templates is key to obtain Pickering nanoemulsions that can be 3D printed through direct ink writing. The combination of such self-assembled templates with the spatial control offered by the printing process allows for the digital manufacturing of hierarchical materials exhibiting thus far inaccessible multiscale porosity and complex geometries.
AUTHOR Sommer, Marianne R. and Alison, Lauriane and Minas, Clara and Tervoort, Elena and Ruhs, Patrick A. and Studart, Andre R.
Title 3D printing of concentrated emulsions into multiphase biocompatible soft materials [Abstract]
Year 2017
Journal/Proceedings Soft Matter
3D printing via direct ink writing (DIW) is a versatile additive manufacturing approach applicable to a variety of materials ranging from ceramics over composites to hydrogels. Due to the mild processing conditions compared to other additive manufacturing methods{,} DIW enables the incorporation of sensitive compounds such as proteins or drugs into the printed structure. Although emulsified oil-in-water systems are commonly used vehicles for such compounds in biomedical{,} pharmaceutical{,} and cosmetic applications{,} printing of such emulsions into architectured soft materials has not been fully exploited and would open new possibilities for the controlled delivery of sensitive compounds. Here{,} we 3D print concentrated emulsions into soft materials{,} whose multiphase architecture allows for site-specific incorporation of both hydrophobic and hydrophilic compounds into the same structure. As a model ink{,} concentrated emulsions stabilized by chitosan-modified silica nanoparticles are studied{,} because they are sufficiently stable against coalescence during the centrifugation step needed to create a bridging network of droplets. The resulting ink is ideal for 3D printing as it displays high yield stress{,} storage modulus and elastic recovery{,} through the formation of networks of droplets as well as of gelled silica nanoparticles in the presence of chitosan. To demonstrate possible architectures{,} we print biocompatible soft materials with tunable hierarchical porosity containing an encapsulated hydrophobic compound positioned in specific locations of the structure. The proposed emulsion-based ink system offers great flexibility in terms of 3D shaping and local compositional control{,} and can potentially help address current challenges involving the delivery of incompatible compounds in biomedical applications.
AUTHOR Ng, Wei Long and Yeong, Wai Yee and Naing, May Win
Title Polyelectrolyte gelatin-chitosan hydrogel optimized for 3D bioprinting in skin tissue engineering [Abstract]
Year 2016
Journal/Proceedings International Journal of Bioprinting
Bioprinting is a promising automated platform that enables the simultaneous deposition of multiple types of cells and biomaterials to fabricate complex three-dimensional (3D) tissue constructs. Most of the previous bioprinting works focused on collagen-based biomaterial, which has poor printability and long crosslinking time. This posed a immerse challenge to create a 3D construct with pre-determined shape and configuration. There is a need for a functional material with good printability in order to fabricate a 3D skin construct. Recently, the use of chitosan for wound healing applications has attracted huge attention due to its attractive traits such as its antimicrobial properties and ability to trigger hemostasis. In this paper, we report the modification of chitosan-based biomaterials for functional 3D bioprinting. Modification to the chitosan was carried out via the oppositely charged functional groups from chitosan and gelatin at a specific pH of ~pH 6.5 to form polyelectrolyte complexes. The polyelectrolyte hydrogels were evaluated in terms of chemical interactions within polymer blend, rheological properties (viscosities, storage and loss modulus), printing resolution at varying pressures and feed rates and biocompatibility. The chitosan-based hydrogels formulated in this work exhibited good printability at room temperature, high shape fidelity of the printed 3D constructs and good biocompatibility with fibroblast skin cells.