Concentric bioprinting of alginate-based tubular constructs using multi-nozzle extrusion-based technique

J Biomedical Materials Res

2017

Self Cite

In this article, mouse fibroblast cells (L929) were seeded on 2%, 5%, and 10% alginate hydrogels, and they were also bio-printed with 2%, 5%, and 10% alginate solutions individually to form constructs. The elastic and viscous moduli of alginate solutions, their interior structure and stiffness, interactions of cells and alginate, cell viability, migration and morphology were investigated by rheometer, MTT assay, scanning electron microscope (SEM), and fluorescent microscopy. The three types of bio-printed scaffolds of distinctive stiffness were prepared, and the seeded cells showed robust viability either on the alginate hydrogel surfaces or in the 3D bio-printed constructs. Majority of the proliferated cells in the 3D bio-printed constructs weakly attached to the surrounding alginate matrix. The concentration of alginate solution and hydrogel stiffness influenced cell migration and morphology, moreover the cells formed spheroids in the bio-printed 10% alginate hydrogel construct. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1009-1018, 2017.

Section: Introductionmentioning

confidence: 99%

Investigation of cell viability and morphology in 3D bio‐printed alginate constructs with tunable stiffness

Shi

Laude

J Biomedical Materials Res

2017

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“…Microneedle, tapered tip, or nozzle based syringe extrusion methods were widely applied in the reported extrusion-based bioprinting approaches7124344. We herein found that the micropipette-based extrusion method is a good approach to print tightly packed PLGA microspheres.…”

Section: Discussionmentioning

confidence: 82%

Hybrid microscaffold-based 3D bioprinting of multi-cellular constructs with high compressive strength: A new biofabrication strategy

Tan

et al. 2016

Sci Rep

Self Cite

106

A hybrid 3D bioprinting approach using porous microscaffolds and extrusion-based printing method is presented. Bioink constitutes of cell-laden poly(D,L-lactic-co-glycolic acid) (PLGA) porous microspheres with thin encapsulation of agarose-collagen composite hydrogel (AC hydrogel). Highly porous microspheres enable cells to adhere and proliferate before printing. Meanwhile, AC hydrogel allows a smooth delivery of cell-laden microspheres (CLMs), with immediate gelation of construct upon printing on cold build platform. Collagen fibrils were formed in the AC hydrogel during culture at body temperature, improving the cell affinity and spreading compared to pure agarose hydrogel. Cells were proven to proliferate in the bioink and the bioprinted construct. High cell viability up to 14 days was observed. The compressive strength of the bioink is more than 100 times superior to those of pure AC hydrogel. A potential alternative in tissue engineering of tissue replacements and biological models is made possible by combining the advantages of the conventional solid scaffolds with the new 3D bioprinting technology.

“…The layer thickness can be affected by other printing parameters such as printing path height, path space and nozzle diameters . Printing numerous layers in the z direction will affect the overall structure and deviates from the intended build …”

Section: Design Factors and The Capabilities Of Bioprintingmentioning

confidence: 99%

“…Materials or bio‐inks formulations are optimized to achieve desired viscosity, yield stress and mechanical integrity for fast shear recovery during and after printing . Some methods of optimization for direct printing includes forming semi‐crosslinked mixture and adding thickening agent . Adding enzyme crosslinker, adjusting temperature of thermosensitive hydrogel, and pre‐exposure of photopolymer to UV light are some methods to improve viscosity of bio‐ink through partially crosslinking the hydrogel.…”

Section: Bioprinting Fabrication Strategiesmentioning

confidence: 99%

“…For instance, when Skardal et al exposed the photopolymer to UV light prior to printing, viscoelasticity of the hydrogel was improved to equate the storage modulus G′ to the loss modulus G′′ for better extrusion . Also, using thickening agents such as hydroxyapatite particles, nanocellulose, xanthum gum, and gellan gum helps to improve the printability of bio‐ink to achieve a suitable viscosity for extrusion bioprinting.…”

Section: Bioprinting Fabrication Strategiesmentioning

confidence: 99%

See 1 more Smart Citation

Design and Printing Strategies in 3D Bioprinting of Cell‐Hydrogels: A Review

Lee

Adv Healthcare Materials

2016

Self Cite

267

189

Bioprinting is an emerging technology that allows the assembling of both living and non‐living biological materials into an ideal complex layout for further tissue maturation. Bioprinting aims to produce engineered tissue or organ in a mechanized, organized, and optimized manner. Various biomaterials and techniques have been utilized to bioprint biological constructs in different shapes, sizes and resolutions. There is a need to systematically discuss and analyze the reported strategies employed to fabricate these constructs. We identified and discussed important design factors in bioprinting, namely shape and resolution, material heterogeneity, and cellular‐material remodeling dynamism. Each design factors are represented by the corresponding process capabilities and printing parameters. The process‐design map will inspire future biomaterials research in these aspects. Design considerations such as data processing, bio‐ink formulation and process selection are discussed. Various printing and crosslinking strategies, with relevant applications, are also systematically reviewed. We categorized them into 5 general bioprinting strategies, including direct bioprinting, in‐process crosslinking, post‐process crosslinking, indirect bioprinting and hybrid bioprinting. The opportunities and outlook in 3D bioprinting are highlighted. This review article will serve as a framework to advance computer‐aided design in bioprinting technologies.