3D printing of metallic micro-gears for micro-fluidic applications

Micro-fluidic devices are essential to handle fluids on the micro-meter scale (micro-scale), making them crucial to biomedical applications, where micro-gear is the key component for active fluid mixing. Rapid and direct fabrication of micro-gears is preferred because they are usually custom-made to specific applications and iterative design is needed. However, conventional manufacturing (CM) techniques for micro-fluidic devices are labor-intensive and time-consuming as multiple steps are required. Three-dimensional (3D) printing, or formally known as additive manufacturing (AM) offers a promising alternative over CM techniques in producing near-net shape complex geometries, given the micro-scale fabrication process. In this work, two types of powder-bed fusion (PBF) AM techniques, namely laser-PBF (L-PBF) and electron beam-PBF (EB-PBF) are used to benchmark 3D-printed micro-gears from stainless steel 316L micro-granular powders. Results showcase the preeminence of L-PBF over EB-PBF in generating distinguishable micro-scale features on gear profiles and superior micro-hardness in mechanical property. Overall, PBF metal AM shows significant promise in advancing the otherwise tedious state of CM for micro-gears.

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3D Printed Microfluidics

Annual Review of Analytical Chemistry ◽

10.1146/annurev-anchem-091619-102649 ◽

2020 ◽

Vol 13 (1) ◽

pp. 45-65 ◽

Cited By ~ 18

Author(s):

Anna V. Nielsen ◽

Michael J. Beauchamp ◽

Gregory P. Nordin ◽

Adam T. Woolley

Keyword(s):

3D Printing ◽

Early Stage ◽

Three Dimensional ◽

Microfluidic Devices ◽

Fabrication Method ◽

Size Scale ◽

Additional Work ◽

Fluidic Devices ◽

3D Printed ◽

Microfabrication Techniques

Traditional microfabrication techniques suffer from several disadvantages, including the inability to create truly three-dimensional (3D) architectures, expensive and time-consuming processes when changing device designs, and difficulty in transitioning from prototyping fabrication to bulk manufacturing. 3D printing is an emerging technique that could overcome these disadvantages. While most 3D printed fluidic devices and features to date have been on the millifluidic size scale, some truly microfluidic devices have been shown. Currently, stereolithography is the most promising approach for routine creation of microfluidic structures, but several approaches under development also have potential. Microfluidic 3D printing is still in an early stage, similar to where polydimethylsiloxane was two decades ago. With additional work to advance printer hardware and software control, expand and improve resin and printing material selections, and realize additional applications for 3D printed devices, we foresee 3D printing becoming the dominant microfluidic fabrication method.

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Benefits And Limitations Of Three-Dimensional Printing Technology For Ecological Research

10.1101/283895 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jocelyn E. Behm ◽

Brenna R. Waite ◽

S. Tonia Hsieh ◽

Matthew R. Helmus

Keyword(s):

3D Printing ◽

New Technology ◽

Wood Fiber ◽

Three Dimensional ◽

Model Organisms ◽

Successful Implementation ◽

Ecological Research ◽

Predator Attack ◽

Custom Made ◽

3D Printed

AbstractBackgroundEcological research often involves sampling and manipulating non-model organisms that reside in heterogeneous environments. As such, ecologists often adapt techniques and ideas from industry and other scientific fields to design and build equipment, tools, and experimental contraptions custom-made for the ecological systems under study. Three-dimensional (3D) printing provides a way to rapidly produce identical and novel objects that could be used in ecological studies, yet ecologists have been slow to adopt this new technology. Here, we provide ecologists with an introduction to 3D printing.ResultsFirst, we give an overview of the ecological research areas in which 3D printing is predicted to be the most impactful and review current studies that have already used 3D printed objects. We then outline a methodological workflow for integrating 3D printing into an ecological research program and give a detailed example of a successful implementation of our 3D printing workflow for 3D printed models of the brown anole, Anolis sagrei, for a field predation study. After testing two print media in the field, we show that the models printed from the less expensive and more sustainable material (blend of 70% plastic and 30% recycled wood fiber) were just as durable and had equal predator attack rates as the more expensive material (100% virgin plastic).ConclusionsOverall, 3D printing can provide time and cost savings to ecologists, and with recent advances in less toxic, biodegradable, and recyclable print materials, ecologists can choose to minimize social and environmental impacts associated with 3D printing. The main hurdles for implementing 3D printing – availability of resources like printers, scanners, and software, as well as reaching proficiency in using 3D image software – may be easier to overcome at institutions with digital imaging centers run by knowledgeable staff. As with any new technology, the benefits of 3D printing are specific to a particular project, and ecologists must consider the investments of developing usable 3D materials for research versus other methods of generating those materials.

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Combining Materials Obtained by 3D-Printing and Electrospinning from Commercial Polylactide Filament to Produce Biocompatible Composites

Polymers ◽

10.3390/polym13213806 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3806

Author(s):

Pablo Romero-Araya ◽

Victor Pino ◽

Ariel Nenen ◽

Verena Cárdenas ◽

Francisca Pavicic ◽

...

Keyword(s):

Mechanical Properties ◽

Tissue Engineering ◽

3D Printing ◽

Three Dimensional ◽

Fibrillar Structure ◽

3D Print ◽

3T3 Fibroblasts ◽

Custom Made ◽

3D Printers ◽

3D Printed

The design of scaffolds to reach similar three-dimensional structures mimicking the natural and fibrous environment of some cells is a challenge for tissue engineering, and 3D-printing and electrospinning highlights from other techniques in the production of scaffolds. The former is a well-known additive manufacturing technique devoted to the production of custom-made structures with mechanical properties similar to tissues and bones found in the human body, but lacks the resolution to produce small and interconnected structures. The latter is a well-studied technique to produce materials possessing a fibrillar structure, having the advantage of producing materials with tuned composition compared with a 3D-print. Taking the advantage that commercial 3D-printers work with polylactide (PLA) based filaments, a biocompatible and biodegradable polymer, in this work we produce PLA-based composites by blending materials obtained by 3D-printing and electrospinning. Porous PLA fibers have been obtained by the electrospinning of recovered PLA from 3D-printer filaments, tuning the mechanical properties by blending PLA with small amounts of polyethylene glycol and hydroxyapatite. A composite has been obtained by blending two layers of 3D-printed pieces with a central mat of PLA fibers. The composite presented a reduced storage modulus as compared with a single 3D-print piece and possessing similar mechanical properties to bone tissues. Furthermore, the biocompatibility of the composites is assessed by a simulated body fluid assay and by culturing composites with 3T3 fibroblasts. We observed that all these composites induce the growing and attaching of fibroblast over the surface of a 3D-printed layer and in the fibrous layer, showing the potential of commercial 3D-printers and filaments to produce scaffolds to be used in bone tissue engineering.

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3D Printed Clamps for In Vitro Tensile Tests of Human Gracilis and the Superficial Third of Quadriceps Tendons

Applied Sciences ◽

10.3390/app11062563 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2563

Author(s):

Ivan Grgić ◽

Vjekoslav Wertheimer ◽

Mirko Karakašić ◽

Željko Ivandić

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Tensile Tests ◽

Biomechanical Properties ◽

Testing Procedure ◽

Laboratory Equipment ◽

Fused Deposition ◽

Custom Made ◽

3D Printed

Recent soft tissue studies have reported issues that occur during experimentation, such as the tissue slipping and rupturing during tensile loads, the lack of standard testing procedure and equipment, the necessity for existing laboratory equipment adaptation, etc. To overcome such issues and fulfil the need for the determination of the biomechanical properties of the human gracilis and the superficial third of the quadriceps tendons, 3D printed clamps with metric thread profile-based geometry were developed. The clamps’ geometry consists of a truncated pyramid pattern, which prevents the tendons from slipping and rupturing. The use of the thread application in the design of the clamp could be used in standard clamping development procedures, unlike in previously custom-made clamps. Fused deposition modeling (FDM) was used as a 3D printing technique, together with polylactic acid (PLA), which was used as a material for clamp printing. The design was confirmed and the experiments were conducted by using porcine and human tendons. The findings justify the usage of 3D printing technology for parts manufacturing in the case of tissue testing and establish independence from the existing machine clamp system, since it was possible to print clamps for each prepared specimen and thus reduce the time for experiment setup.

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Recurrent contracted sockets treated with personalized, three-dimensionally printed conformers and buccal grafts

European Journal of Ophthalmology ◽

10.1177/11206721211000013 ◽

2021 ◽

pp. 112067212110000

Author(s):

Annabel LW Groot ◽

Jelmer S Remmers ◽

Roel JHM Kloos ◽

Peerooz Saeed ◽

Dyonne T Hartong

Keyword(s):

Three Dimensional ◽

Case Series ◽

Secondary Outcome ◽

Retrospective Case ◽

Upper Eyelid ◽

Ocular Prosthesis ◽

Buccal Mucosal Graft ◽

Custom Made ◽

3D Printed

Purpose: Recurrent contracted sockets are complex situations where previous surgeries have failed, disabling the wear of an ocular prosthesis. A combined method of surgery and long-term fixation using custom-made, three-dimensional (3D) printed conformers is evaluated. Methods: Retrospective case series of nine patients with recurrent excessive socket contraction and inability to wear a prosthesis, caused by chemical burns ( n = 3), fireworks ( n = 3), trauma ( n = 2) and enucleation and radiotherapy at childhood due to optic nerve glioma ( n = 1) with three average previous socket surgeries (range 2–6). Treatment consisted of a buccal mucosal graft and personalized 3D-printed conformer designed to be fixated to the periosteum and tarsal plates for minimal 2 months. Primary outcome was the retention of an ocular prosthesis. Secondary outcome was the need for additional surgeries. Results: Outcomes were measured at final follow-up between 7 and 36 months postoperatively (mean 20 months). Eight cases were able to wear an ocular prosthesis after 2 months. Three cases initially treated for only the upper or only the lower fornix needed subsequent surgery for the opposite fornix for functional reasons. Two cases had later surgery for cosmetic improvement of upper eyelid position. Despite pre-existing lid abnormalities (scar, entropion, lash deficiency), cosmetic outcome was judged highly acceptable in six cases because of symmetric contour and volume, and reasonably acceptable in the remaining two. Conclusions: Buccal mucosal transplant fixated with a personalized 3D-designed conformer enables retention of a well-fitted ocular prosthesis in previously failed socket surgeries. Initial treatment of both upper and lower fornices is recommended to avoid subsequent surgeries for functional reasons.

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Three-dimensional printing for heart diseases: clinical application review

Bio-Design and Manufacturing ◽

10.1007/s42242-021-00125-8 ◽

2021 ◽

Author(s):

Yanyan Ma ◽

Peng Ding ◽

Lanlan Li ◽

Yang Liu ◽

Ping Jin ◽

...

Keyword(s):

3D Printing ◽

Clinical Application ◽

Heart Diseases ◽

Three Dimensional ◽

Convincing Evidence ◽

Surgical Interventions ◽

Three Dimensional Printing ◽

Complex Anatomy ◽

Precise Understanding ◽

3D Printed

AbstractHeart diseases remain the top threat to human health, and the treatment of heart diseases changes with each passing day. Convincing evidence shows that three-dimensional (3D) printing allows for a more precise understanding of the complex anatomy associated with various heart diseases. In addition, 3D-printed models of cardiac diseases may serve as effective educational tools and for hands-on simulation of surgical interventions. We introduce examples of the clinical applications of different types of 3D printing based on specific cases and clinical application scenarios of 3D printing in treating heart diseases. We also discuss the limitations and clinically unmet needs of 3D printing in this context.

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Three-Dimensional Printing of Hydroxyapatite Composites for Biomedical Application

Crystals ◽

10.3390/cryst11040353 ◽

2021 ◽

Vol 11 (4) ◽

pp. 353

Author(s):

Yanting Han ◽

Qianqian Wei ◽

Pengbo Chang ◽

Kehui Hu ◽

Oseweuba Valentine Okoro ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Biomedical Application ◽

Three Dimensional ◽

Antibacterial Properties ◽

Natural Polymers ◽

Three Dimensional Printing ◽

3D Printed ◽

Dental Applications ◽

Hard Tissue Engineering

Hydroxyapatite (HA) and HA-based nanocomposites have been recognized as ideal biomaterials in hard tissue engineering because of their compositional similarity to bioapatite. However, the traditional HA-based nanocomposites fabrication techniques still limit the utilization of HA in bone, cartilage, dental, applications, and other fields. In recent years, three-dimensional (3D) printing has been shown to provide a fast, precise, controllable, and scalable fabrication approach for the synthesis of HA-based scaffolds. This review therefore explores available 3D printing technologies for the preparation of porous HA-based nanocomposites. In the present review, different 3D printed HA-based scaffolds composited with natural polymers and/or synthetic polymers are discussed. Furthermore, the desired properties of HA-based composites via 3D printing such as porosity, mechanical properties, biodegradability, and antibacterial properties are extensively explored. Lastly, the applications and the next generation of HA-based nanocomposites for tissue engineering are discussed.

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Three-dimensionally printed polycaprolactone/multicomponent bioactive glass scaffolds for potential application in bone tissue engineering

Biomedical glasses ◽

10.1515/bglass-2020-0006 ◽

2020 ◽

Vol 6 (1) ◽

pp. 57-69

Author(s):

Amirhosein Fathi ◽

Farzad Kermani ◽

Aliasghar Behnamghader ◽

Sara Banijamali ◽

Masoud Mozafari ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Three Dimensional ◽

Layer By Layer ◽

Composite Scaffolds ◽

3D Printed ◽

Co Doped

AbstractOver the last years, three-dimensional (3D) printing has been successfully applied to produce suitable substitutes for treating bone defects. In this work, 3D printed composite scaffolds of polycaprolactone (PCL) and strontium (Sr)- and cobalt (Co)-doped multi-component melt-derived bioactive glasses (BGs) were prepared for bone tissue engineering strategies. For this purpose, 30% of as-prepared BG particles (size <38 μm) were incorporated into PCL, and then the obtained composite mix was introduced into a 3D printing machine to fabricate layer-by-layer porous structures with the size of 12 × 12 × 2 mm3.The scaffolds were fully characterized through a series of physico-chemical and biological assays. Adding the BGs to PCL led to an improvement in the compressive strength of the fabricated scaffolds and increased their hydrophilicity. Furthermore, the PCL/BG scaffolds showed apatite-forming ability (i.e., bioactivity behavior) after being immersed in simulated body fluid (SBF). The in vitro cellular examinations revealed the cytocompatibility of the scaffolds and confirmed them as suitable substrates for the adhesion and proliferation of MG-63 osteosarcoma cells. In conclusion, 3D printed composite scaffolds made of PCL and Sr- and Co-doped BGs might be potentially-beneficial bone replacements, and the achieved results motivate further research on these materials.

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3D printing of a bio-based ink made of cross-linked cellulose nanofibrils with various metal cations

Scientific Reports ◽

10.1038/s41598-021-85865-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

J. Benedikt Mietner ◽

Xuehe Jiang ◽

Ulrica Edlund ◽

Bodo Saake ◽

Julien R. G. Navarro

Keyword(s):

3D Printing ◽

Divalent Cations ◽

Cellulose Nanofibrils ◽

Three Dimensional ◽

Metal Cations ◽

Cross Link ◽

Cellulose Pulp ◽

Freeze Dried ◽

3D Printed ◽

Metallic Cations

AbstractIn this work, we present an approach to cross-link cellulose nanofibrils (CNFs) with various metallic cations (Fe3+, Al3+, Ca2+, and Mg2+) to produce inks suitable for three-dimensional (3D) printing application. The printability of each hydrogel ink was evaluated, and several parameters such as the optimal ratio of Mn+:TOCNF:H2O were discussed. CNF suspensions were produced by mechanical disintegration of cellulose pulp with a microfluidizer and then oxidized with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). Finally, metal cations were introduced to the deprotonated TEMPO-oxidized CNF (TOCNF) suspension to cross-link the nanofibrils and form the corresponding hydrogels. The performances of each gel-ink were evaluated by rheological measurements and 3D printing. Only the gels incorporated with divalent cations Ca2+ and Mg2+ were suitable for 3D printing. The 3D printed structures were freeze-dried and characterized with Fourier transform infrared spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). The better interaction of the TOCNFs with the divalent metallic cations in terms of printability, the viscoelastic properties of the inks, and the variation trends owing to various metal cations and ratios are discussed.

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A review on the role of 3D printing in the fight against COVID-19: safety and challenges

Rapid Prototyping Journal ◽

10.1108/rpj-08-2020-0198 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Sapam Ningthemba Singh ◽

Vavilada Satya Swamy Venkatesh ◽

Ashish Bhalchandra Deoghare

Keyword(s):

Supply Chain ◽

3D Printing ◽

Three Dimensional ◽

Content Type ◽

Medical Supplies ◽

Future Challenges ◽

Safety And Reliability ◽

3D Printed ◽

Comprehensive Study

Purpose During the COVID-19 pandemic, the three-dimensional (3D) printing community is actively participating to address the supply chain gap of essential medical supplies such as face masks, face shields, door adapters, test swabs and ventilator valves. This paper aims to present a comprehensive study on the role of 3D printing during the coronavirus (COVID-19) pandemic, its safety and its challenges. Design/methodology/approach This review paper focuses on the applications of 3D printing in the fight against COVID-19 along with the safety and challenges associated with 3D printing to fight COVID-19. The literature presented in this paper is collected from the journal indexing engines including Scopus, Google Scholar, ResearchGate, PubMed, Web of Science, etc. The main keywords used for searches were 3D printing COVID-19, Safety of 3D printed parts, Sustainability of 3D printing, etc. Further possible iterations of the keywords were used to collect the literature. Findings The applications of 3D printing in the fight against COVID-19 are 3D printed face masks, shields, ventilator valves, test swabs, drug deliveries and hands-free door adapters. As most of these measures are implemented hastily, the safety and reliability of these parts often lacked approval. The safety concerns include the safety of the printed parts, operators and secondary personnel such as the workers in material preparation and transportation. The future challenges include sustainability of the process, long term supply chain, intellectual property and royalty-free models, etc. Originality/value This paper presents a comprehensive study on the applications of 3D printing in the fight against COVID-19 with emphasis on the safety and challenges in it.

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