Biological gum-based biopolymers as advanced materials for 3D printing applications: A review

As a modern manufacturing technique, three dimensional (3D) printing allows the production of customized 3D constructs with unprecedented degrees of flexibility in design. Nowadays, various sectors are exploiting 3D printing to develop inordinately complex architectures with extra benefitting features including the light weight and accurate dimensions of the design among others. When it comes to human-relevant applications, a critical concern is the use of non-toxic biodegradable and biocompatible compounds for formulating the ink. Biological gums such as alginate, xanthan, carrageenan, guar gum, gellan gum, gum rosin, konjac gum, locust bean gum, and gum arabic are particularly attractive for fabricating 3D printing inks due to their biodegradability, abundance, accessibility, and low cost. Gum-based inks possess proper pseudoplastic behavior which along with unique thixotropic attributes and robust mechanical features have made them proper candidates for developing 3D structures with diverse geometries. This review begins with an overview of the historical perspectives on the use of gums in 3D printing applications, followed by a discussion of the key practical considerations for their application in additive manufacturing. Additionally, the latest advancements and techniques employed to enhance their printability are systematically presented. We also provided detailed insight into the characteristics of popular gums used in 3D-printed applications. The final section described the application of gum-based inks in various sectors. Current challenges and future perspectives of 3D printing with gum-based inks are also discussed to shed light on the road ahead of the application of these materials.