3D printing of concentrated emulsions into multiphase biocompatible soft materials. Issue 9 (6th February 2017)

• Record Type: Journal Article
• Authors: Sommer, Marianne R.; Alison, Lauriane; Minas, Clara; Tervoort, Elena; Rühs, Patrick A.; Studart, André R.
• Is Part Of: Soft matter. Volume 13:Issue 9(2017)
• Page Start: 1794
• Page End: 1803
• Publication Date: 2017-02-06
• Subjects: Soft condensed matter -- Periodicals; 530.413
• DOI: 10.1039/c6sm02682f
• Languages: English
• ISSNs: 1744-683X

Abstract

Abstract : 3D printed concentrated emulsions form soft materials with multiphase architecture allowing for the site-specific incorporation of sensitive compounds. Abstract : 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.