Review Cite This: Biomacromolecules 2018, 19, 701−711
pubs.acs.org/Biomac
Potential and Limitations of Nanocelluloses as Components in Biocomposite Inks for Three-Dimensional Bioprinting and for Biomedical Devices Gary Chinga-Carrasco* Biomacromolecules 2018.19:701-711. Downloaded from pubs.acs.org by UNIV OF CALIFORNIA SANTA BARBARA on 01/02/19. For personal use only.
Lead Scientist−Biocomposites, RISE PFI, Høgskoleringen 6b, 7491 Trondheim, Norway ABSTRACT: Three-dimensional (3D) printing has rapidly emerged as a new technology with a wide range of applications that includes biomedicine. Some common 3D printing methods are based on the suitability of biopolymers to be extruded through a nozzle to construct a 3D structure layer by layer. Nanocelluloses with specific rheological characteristics are suitable components to form inks for 3D printing. This review considers various nanocelluloses that have been proposed for 3D printing with a focus on the potential advantages, limitations, and requirements when used for biomedical devices and when used in contact with the human body.
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INTRODUCTION Three-dimensional (3D) printing has been a focus for some years. Good reviews have been written about several techniques for 3D printing, including fused deposition modeling, selective laser sintering, and stereolithography.1 Such techniques are applied for 3D printing of solid constructs using polymers such as polylactic acid (PLA) and polyhydroxyalkanoates (PHA) used in biomedical applications.2 In this review, focus will be put on studies where nanocelluloses have been used as hydrogels for 3D printing. Note that hydrogels are classified as inks in the context of 3D printing.3 Furthermore, 3D printing that involves the controlled deposition of cell-laden inks (bioinks) for tissue engineering is commonly referred to as 3D bioprinting. Hence, the term 3D printing will be used generally, and 3D bioprinting will be used specifically in cases where a bioink contains living cells. The three main technologies for depositing bioinks are inkjet, laserassisted, and extrusion bioprinting (Figure 1). Currently, the extrusion systems have been the preferred methods for 3D bioprinting of nanocellulose-based inks. Extrusion systems are capable of printing complex and cell compatible 3D constructs.5 The purpose of the present work is to review some advances in the development of nanocelluloses and 3D printing as an emerging technology for biomedical applications. Hence, nanocellulose will be reviewed as a biomaterial, focusing on the capability of various nanocelluloses to be 3D printed and addressing some aspects that are recommended for biomedical devices.
structurally homogeneous nanofibrils having typical widths in the nanometer scale (
