Name: stereolithographic 3d printing with renewable acrylates
Uploaded: 2018-09-12T15:00:00.000+00:00
Duration: 8 min 28 s
Description: Watch this Scientific Journal Video about Stereolithographic 3D Printing with Renewable Acrylates at JoVE.com

Este estudo foi suportado por centro de aplicação de polímero de GreenPAC como parte do projeto 140413: "impressão 3D na produção". Nós gostaríamos de reconhecer Albert Hartman, Corinne van Noordenne, Rens van Leeuwen, Anniek Bruins, Femke Tamminga, Jur van Dijken e Albert Woortman para facilitar as filmagens de vídeo.

Atenção: Por favor consulte todas as fichas de dados de segurança (MSDS) antes do uso.
1. preparação da resina Photocurable
Nota: Por favor, use equipamento protetor pessoal (óculos de segurança, luvas, avental, etc.) durante o procedimento a seguir. Consulte nosso trabalho anterior12 para mais detalhes sobre esta seção.
<ol><li>Coloque 50 g de 1,10-decanediol diacrylate (SA5201) em um Erlenmeyer de 500 mL.</li>
	<li>Adicionar 1,0 g de diphenyl(2,4,6-trimethylbenzoyl) óxido de fosfina (TPO) e 0,40 g de 2,5 -bis(5 -tert-butil-benzoxazol-2-yl) tiofeno (BBOT) ao balão.</li>
	<li>Equipar o balão com um agitador mecânico e agitar a mistura a 200 rpm por 5 min à temperatura ambiente, a fim de dissolver o TPO e BBOT No monómero de acrilato.</li>
	<li>Adicionar 100 g de triacrilato de pentaeritritol e 100 g de acrilato de epóxi multifuncional (ver Tabela de materiais) para a mistura.</li>
	<li>Agite a mistura a 200 rpm por 30 min a 50 ° C, para garantir uma resina homogênea.</li>
	<li>Retire o agitador mecânico e caber o frasco com uma rolha. O frasco é envolto em folha de alumínio para proteger a resina de fotopolímero biobased acrilato (BAPR) da luz. Nota: O protocolo pode ser pausado aqui.</li>
	<li>Cobrir a placa inferior de um rheometer com geometria paralelo-placa com o photoresin.</li>
	<li>Ajustar a distância entre as placas de 1 mm e cobrir o rheometer com uma capa resistente a UV.</li>
	<li>Medir a viscosidade da resina à temperatura ambiente em taxas de cisalhamento de 0,1 a 100 s-1; por exemplo,0,100, 0,126, 0,158, 0.200, 0.251, 0,316, 0,398, 0.501, 0.631, 0.794, 1.00, 1,26, 1.58, 2,00, 2,51, 3.16, 3,98, 5.01, 6.31, 7.94, 10.0, 12,6, 15,8, 20,0, 25,1, 31,6, 39,8, 50,1, 63.1, 79,4 e 100 s-1.</li>
</ol>2. Stereolithographic impressão 3D com Biobased Acrylates
Nota: Consulte nosso trabalho anterior12 para mais detalhes sobre esta seção.
<ol><li>Ligue a impressora 3D de SLA e selecione o modo de abertura.</li>
	<li>Inicie o software de preparação de modelo em um computador. Escolha configurações de impressão desejado: material (Clear), versão (V4) e espessura de camada (50 µm).</li>
	<li>Abra o modelo digital do complexo em forma de protótipo, um arquivo de idioma (. STL) padrão de mosaico (consulte o Arquivo de codificação suplementar) e escolha a localização e a orientação sobre a plataforma de compilação.  Carregar o trabalho de impressão a partir do software de elaboração de modelo para a impressora 3D de SLA. Nota: Dependendo da arquitetura do produto, uma estrutura de apoio pode ser integrada no modelo 3D para estabilizar a construção durante a fabricação. No caso do complexo em forma de protótipo demonstrado aqui, uma estrutura de apoio não é necessária se impresso normal à direção de compilação.</li>
	<li>200 mL de photoresin a biobased despeje um tanque de resina. Abra a impressora 3D e montar o tanque de resina corretamente.</li>
	<li>Montar a plataforma de compilação e feche a impressora 3D.</li>
	<li>Inicie o trabalho de impressão.</li>
	<li>Permitir que a impressora 3D fabricar protótipos de forma complexos.  Não abra a impressora até que o trabalho de impressão é concluído. Nota: Antes de imprimir, certifique-se que a impressora 3D é nivelada. Para o protocolo demonstrado, o comprimento de onda do laser UV é a 405 nm. O momento da impressão do objeto é 2,5 h.</li>
</ol>3. pós-tratamento de 3D impresso objetos
Nota: Use equipamento de proteção pessoal (óculos de segurança, luvas) durante o procedimento a seguir.
<ol><li>Quando o trabalho de impressão for concluído, abra a impressora. Retire a plataforma de compilação, com as peças produzidas anexadas e feche a impressora.</li>
	<li>Abra a estação de lavagem, preenchida com álcool isopropílico e inserir a plataforma de compilação. Inicie o procedimento e enxaguar por 20 min remover qualquer resina não tenha reagida.</li>
	<li>Quando for concluído o procedimento de lavagem, remover a plataforma de compilação da estação de lavagem e separe os protótipos da plataforma de compilação.</li>
	<li>Os protótipos para o ar deixe secar por 30 min. Entretanto, pré-aquecer o forno UV a 60 ° C. Nota: O pré-aquecimento levará pelo menos 15 min. O comprimento de onda UV do forno é de 405 nm, idêntico ao comprimento de onda do laser SLA.</li>
	<li>Abrir o forno UV e rapidamente Coloque os protótipos na plataforma rotativa. Feche o forno UV e cura para 60 min a 60 ° C para assegurar a conversão completa.</li>
	<li>Quando terminar o procedimento pós-curando, abra o forno UV e tirar os protótipos.</li>
</ol>4. Caracterização da morfologia superficial de protótipos em forma de complexo
Nota: Consulte nosso trabalho anterior12 para mais detalhes sobre esta seção.
<ol><li>Corte ca. 1 cm da hélice interna do protótipo de forma complexo, usando uma lâmina de barbear.</li>
	<li>Anexe a amostra para o porta-amostras com condutor fita dupla face de carbono.</li>
	<li>Antes da imagem latente, revestir a amostra com 30 nm Pt/Pd (80: 20) em um sistema de pulverização catódica.</li>
	<li>Inserir a amostra em um microscópio eletrônico de varredura operando a uma tensão de aceleração de 5 kV. Adquira várias imagens da amostra em 30 X e ampliação de X 120.</li>
</ol>

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Fabricação de aditiva é aplicada na fabricação de Tailor-Made protótipos e pequenas séries, quando os custos de produção mais elevados por parte podem competir com processos convencionais, desde que não há nenhuma necessidade para a produção de moldes e ferramentas. Na última década, as receitas de serviços e produtos relacionados à fabricação de aditiva tem crescido exponencialmente,13. A maior fração de vendas de material é de fotopolímeros. O crescimento atraiu atenção ...

Prototipagem rápida permite liberdade de design e produção por demanda e permite que a fabricação eficiente de 3D constrói-se em uma forma de camada por camada1. Como resultado, a impressão 3D como uma técnica de fabricação desenvolveu rapidamente em anos recentes2. Várias tecnologias estão disponíveis, todos contando com a tradução de modelos virtuais em objetos físicos e aplicação de processos, tais como extrusão, deposição de energia direta, solidificação de pó, laminação de folha e fotopolimerização. Este último envolve gradual de cura UV de resinas de fotopolímero líquido. Em 1986, casco e cooperadores desenvolveram o aparelho estereolitografia (SLA), uma impressora 3D baseados em laser UV. Mais recentemente, um processo similar chamado digital light processing (DLP) tornou-se disponível, no qual fotopolimerização é iniciada por um projetor. Juntos, DLP e SLA são referidos como estereolitografia 3D impressão3.
SLA é aplicado em prototipagem de alta resolução e fabricação de dispositivos biomédicos4,5. Esta tecnologia é superior à deposição fundida amplamente utilizado (FDM) de modelagem em termos de precisão, acabamento de superfície e resolução6. Dependendo da arquitetura do produto, uma estrutura de apoio é integrada no modelo 3D para estabilizar a construção durante a fabricação. Além disso, um tratamento pós-impressão de peças fabricadas é necessário7,8. Normalmente, objetos impressos são lavados em um banho de álcool para dissolver a resina não tenha reagida, e posterior cura em um forno UV é executada para garantir a conversão completa da polimerização9.
Em geral, resinas para fabricação de aditiva baseados em litografia dependem photocurable sistemas contendo multifuncional acrilatos ou epóxidos10. Resinas de fotopolímero atual no mercado comercial são baseados em fósseis e caro, enquanto a disponibilidade de resinas renováveis de baixo custo é necessária para facilitar a fabricação local e livre de resíduos de produtos sustentáveis de 3D para uma economia de biobased1 , 6. recentemente, resinas de fotopolímero, com base em renováveis acrilatos foram desenvolvidas e aplicadas com sucesso em estereolitografia 3D impressão11,12. Neste protocolo detalhado, demonstramos a prototipagem rápida com resinas recicladas em um equipamento de estereolitografia comercial. É dada especial atenção à críticas etapas no procedimento, ou seja, tratamentos pós-impressão e formulação resina, para ajudar novos actores no domínio da fabricação aditiva.

<table><tbody><tr><td>Isobornyl acrylate&amp;nbsp;</td><td>Sartomer</td><td>SA5102</td><td>Acrylate monomer</td></tr><tr><td>1,10-decanediol diacrylate</td><td>Sartomer</td><td>SA5201</td><td>Acrylate monomer</td></tr><tr><td>Pentaerythritol tetraacrylate</td><td>Sartomer</td><td>SA5400</td><td>Acrylate monomer</td></tr><tr><td>Multifunctional epoxy acrylate</td><td>Sartomer</td><td>SA7101</td><td>Acrylate oligomer</td></tr><tr><td>Diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO), 97%</td><td>Sigma Aldrich</td><td>415952</td><td>Photoinitiator</td></tr><tr><td>2,5-bis(5-&lt;em&gt;tert&lt;/em&gt;-butyl-benzoxazol-2-yl)thiophene (BBOT), 99%</td><td>Sigma Aldrich</td><td>223999</td><td>Optical absorber</td></tr><tr><td>Isopropyl alcohol (IPA), 99%</td><td>Bleko</td><td>1010500</td><td>For alcohol bath (applied in Form Wash)</td></tr><tr><td>Paar Physica MCR300&amp;nbsp;</td><td>Anton Paar</td><td>-</td><td>Rheometer with parallel plate geometry</td></tr><tr><td>Form 2 Printer</td><td>Formlabs</td><td>-</td><td>Desktop SLA 3D printer</td></tr><tr><td>Form Wash&amp;nbsp;</td><td>Formlabs</td><td>-</td><td>Washing station</td></tr><tr><td>Form Cure</td><td>Formlabs</td><td>-</td><td>UV oven</td></tr><tr><td>Instron 4301 1KN Series IX</td><td>Instron</td><td>-</td><td>Universal testing machine</td></tr><tr><td>Philips XL30 ESEM-FEG&amp;nbsp;</td><td>Philips</td><td>-</td><td>Scanning electron microscope</td></tr></tbody></table>

stereolithographic 3d printing with renewable acrylates

A acessibilidade de materiais renováveis custo-do competidor e sua aplicação na fabricação de aditiva é essencial para uma economia eficiente recicladas. Demonstramos a prototipagem rápida de resinas sustentáveis, usando uma impressora 3D stereolithographic. Formulação da resina ocorre pela simples mistura de biobased acrilato monômeros e oligômeros com um photoinitiatior e absorvente de óptico. Viscosidade da resina é controlada pelo monômero relação oligómero e é determinada em função da taxa de cisalhamento por um rheometer com geometria placa paralela. Um aparelho de stereolithographic cobrado com as resinas recicladas é empregado para produzir protótipos de forma complexos com alta precisão. Os produtos requerem um pós-tratamento, incluindo o álcool enxaguando e irradiação UV, para assegurar a cura completa. A característica de alta resolução e excelente superfície de acabamento dos protótipos é revelado por microscopia eletrônica.

Quatro composições representativas da resina são exibidas na tabela 1, juntamente com seu conteúdo de carbono médio biobased (BC) derivado do BC individual dos componentes. A viscosidade da resina (Figura 1) é influenciada pela relação de acrilato monômeros e oligômeros e normalmente demonstra comportamento Newtoniano. As propriedades mecânicas de peças fabricadas a partir de várias resinas foram determinadas pela análise de ten...

Watch this Scientific Journal Video about Stereolithographic 3D Printing with Renewable Acrylates at JoVE.com

Stereolithographic 3D Printing with Renewable Acrylates

Um protocolo para a fabricação de aditivo com resinas renováveis fotopolímero em um equipamento de estereolitografia é apresentado.

Stereolithographic de impressão 3D com acrilatos renováveis

The accessibility of cost-competitive renewable materials and their application in additive manufacturing is essential for an efficient biobased economy. ...

stereolithographic-3d-printing-with-renewable-acrylates

Research

JoVE Journal

Chemistry

9.4K visualizações.  NHL Stenden University of Applied Sciences. Um protocolo para a fabricação de aditivo com resinas renováveis fotopolímero em um equipamento de estereolitografia é apresentado.

Vídeo: Stereolithographic 3D Printing with Renewable Acrylates

Planar and Three-Dimensional Printing of Conductive Inks

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical devices1-3. In this paper, we focus on one- (1D), two- (2D), and three-dimensional (3D) printing of conductive metallic inks in the form of flexible, stretchable, and spanning microelectrodes.
Direct-write assembly4,5 is a 1-to-3D printing technique that enables the fabrication of features ranging from simple lines to complex structures by the deposition of concentrated inks through fine nozzles (~0.1 - 250 &mu;m). This printing method consists of a computer-controlled 3-axis translation stage, an ink reservoir and nozzle, and 10x telescopic lens for visualization. Unlike inkjet printing, a droplet-based process, direct-write assembly involves the extrusion of ink filaments either in- or out-of-plane. The printed filaments typically conform to the nozzle size. Hence, microscale features (&lt; 1 &mu;m) can be patterned and assembled into larger arrays and multidimensional architectures.
In this paper, we first synthesize a highly concentrated silver nanoparticle ink for planar and 3D printing via direct-write assembly. Next, a standard protocol for printing microelectrodes in multidimensional motifs is demonstrated. Finally, applications of printed microelectrodes for electrically small antennas, solar cells, and light-emitting diodes are highlighted.

Planar and three-dimensional printing of conductive metallic inks is described. Our approach provides new avenues for fabricating printed electronic, optoelectronic, and biomedical devices in unusual layouts at the microscale.

Impressão de planar e tridimensional de tintas condutoras

Printed electronics rely on low-cost, large-area fabrication routes to create flexible or multidimensional electronic, optoelectronic, and biomedical ...

Bioengenharia

3D Printing of Biomolecular Models for Research and Pedagogy

The construction of physical three-dimensional (3D) models of biomolecules can uniquely contribute to the study of the structure-function relationship. 3D structures are most often perceived using the two-dimensional and exclusively visual medium of the computer screen. Converting digital 3D molecular data into real objects enables information to be perceived through an expanded range of human senses, including direct stereoscopic vision, touch, and interaction. Such tangible models facilitate new insights, enable hypothesis testing, and serve as psychological or sensory anchors for conceptual information about the functions of biomolecules. Recent advances in consumer 3D printing technology enable, for the first time, the cost-effective fabrication of high-quality and scientifically accurate models of biomolecules in a variety of molecular representations. However, the optimization of the virtual model and its printing parameters is difficult and time consuming without detailed guidance. Here, we provide a guide on the digital design and physical fabrication of biomolecule models for research and pedagogy using open source or low-cost software and low-cost 3D printers that use fused filament fabrication technology.

Physical models of biomolecules can facilitate an understanding of their structure-function for the researcher, aid in communication between researchers, and serve as an educational tool in pedagogical endeavors. Here, we provide detailed guidance for the 3D printing of accurate models of biomolecules using fused filament fabrication desktop 3D printers.

Impressão 3D de biomoleculares Modelos de Investigação e Pedagogia

The construction of physical three-dimensional (3D) models of biomolecules can uniquely contribute to the study of the structure-function relationship. 3D ...

Engenharia

Printing Thermoresponsive Reverse Molds for the Creation of Patterned Two-component Hydrogels for 3D Cell Culture

Bioprinting is an emerging technology that has its origins in the rapid prototyping industry. The different printing processes can be divided into contact bioprinting1-4 (extrusion, dip pen and soft lithography), contactless bioprinting5-7 (laser forward transfer, ink-jet deposition) and laser based techniques such as two photon photopolymerization8. It can be used for many applications such as tissue engineering9-13, biosensor microfabrication14-16 and as a tool to answer basic biological questions such as influences of co-culturing of different cell types17. Unlike common photolithographic or soft-lithographic methods, extrusion bioprinting has the advantage that it does not require a separate mask or stamp. Using CAD software, the design of the structure can quickly be changed and adjusted according to the requirements of the operator. This makes bioprinting more flexible than lithography-based approaches.
Here we demonstrate the printing of a sacrificial mold to create a multi-material 3D structure using an array of pillars within a hydrogel as an example. These pillars could represent hollow structures for a vascular network or the tubes within a nerve guide conduit. The material chosen for the sacrificial mold was poloxamer 407, a thermoresponsive polymer with excellent printing properties which is liquid at 4 &deg;C and a solid above its gelation temperature ~20 &deg;C for 24.5% w/v solutions18. This property allows the poloxamer-based sacrificial mold to be eluted on demand and has advantages over the slow dissolution of a solid material especially for narrow geometries. Poloxamer was printed on microscope glass slides to create the sacrificial mold. Agarose was pipetted into the mold and cooled until gelation. After elution of the poloxamer in ice cold water, the voids in the agarose mold were filled with alginate methacrylate spiked with FITC labeled fibrinogen. The filled voids were then cross-linked with UV and the construct was imaged with an epi-fluorescence microscope.

A bioprinter was used to create patterned hydrogels based on a sacrificial mold. The poloxamer mold was backfilled with a second hydrogel and then eluted, leaving voids which were filled with a third hydrogel. This method uses fast elution and good printability of poloxamer to generate complex architectures from biopolymers.

Impressão de Moldes reversa Thermoresponsive para a Criação de Patterned hidrogéis de dois componentes para Cultura de Células em 3D

Bioprinting is an emerging technology that has its origins in the rapid prototyping industry. The different printing processes can be divided into contact ...

Imunologia e Infecção

Procedure for the Transfer of Polymer Films Onto Porous Substrates with Minimized Defects

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support substrates. Accomplishing this transfer in a highly controlled, mechanized, and reproducible manner can eliminate the creation of macroscale defect structures (e.g., tears, cracks, and wrinkles) within the thin film that compromise device performance and the usable area per sample. Here, we describe a general protocol for the highly controlled and mechanized transfer of a polymeric thin film onto an arbitrary porous support substrate for eventual use as a water filtration membrane device. Specifically, we fabricate a block copolymer (BCP) thin film on top of a sacrificial, water-soluble poly(acrylic acid) (PAA) layer and silicon wafer substrate. We then utilize a custom-designed, 3D-printed transfer tool and drain chamber system to deposit, lift-off, and transfer the BCP thin film onto the center of a porous anodized aluminum oxide (AAO) support disc. The transferred BCP thin film is shown to be consistently placed onto the center of the support surface due to the guidance of the meniscus formed between the water and the 3D-printed plastic drain chamber. We also compare our mechanized transfer-processed thin films to those that have been transferred by hand with the use of tweezers. Optical inspection and image analysis of the transferred thin films from the mechanized process confirm that little-to-no macroscale inhomogeneities or plastic deformations are produced, as compared to the multitude of tears and wrinkles produced from manual transfer by hand. Our results suggest that the proposed strategy for thin film transfer can reduce defects when compared to other methods across many systems and applications.

We present a procedure for highly controlled and wrinkle-free transfer of block copolymer thin films onto porous support substrates using a 3D-printed drain chamber. The drain chamber design is of general relevance to all procedures involving transfer of macromolecular films onto porous substrates, which is normally done by hand in an irreproducible fashion.

Procedimento para transferência de películas de polímero para substratos porosos com defeitos minimizados

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support ...

Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper composition, targeted modulus, and well-defined architectural features. Biomaterials that recapitulate the intrinsic architecture of in vivo tissue are vital for studying diseases as well as to facilitate the regeneration of lost and malformed soft tissue. A novel biofabrication technique was developed which combines state of the art imaging, three-dimensional (3D) printing, and selective enzymatic activity to create a new generation of biomaterials for research and clinical application. The developed material, Bovine Serum Albumin rubber, is reaction injected into a mold that upholds specific geometrical features. This sacrificial material allows the adequate transfer of architectural features to a natural scaffold material. The prototype consists of a 3D collagen scaffold with 4 and 3 mm channels that represent a branched architecture. This paper emphasizes the use of this biofabrication technique for the generation of natural constructs. This protocol utilizes a computer-aided software (CAD) to manufacture a solid mold which will be reaction injected with BSA rubber followed by the enzymatic digestion of the rubber, leaving its architectural features within the scaffold material.

An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

Tridimensional Tecnologia Biomimético: Novel Biorubber Cria Definido micro e macro-escala Arquitecturas em colágeno hidrogéis

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper ...

Multimodal 3D Printing of Phantoms to Simulate Biological Tissue

Biomedical optical imaging is playing an important role in diagnosis and treatment of various diseases. However, the accuracy and the reproducibility of an optical imaging device are greatly affected by the performance characteristics of its components, the test environment, and the operations. Therefore, it is necessary to calibrate these devices by traceable phantom standards. However, most of the currently available phantoms are homogeneous phantoms that cannot simulate multimodal and dynamic characteristics of biological tissue. Here, we show the fabrication of heterogeneous tissue-simulating phantoms using a production line integrating a spin coating module, a polyjet module, a fused deposition modeling (FDM) module, and an automatic control framework. The structural information and the optical parameters of a &#34;digital optical phantom&#34; are defined in a prototype file, imported to the production line, and fabricated layer-by-layer with sequential switch between different printing modalities. Technical capability of such a production line is exemplified by the automatic printing of skin-simulating phantoms that comprise the epidermis, dermis, subcutaneous tissue, and an embedded tumor.

Spin coating, polyjet printing, and fused deposition modeling are integrated to produce multilayered heterogeneous phantoms that simulate structural and functional properties of biological tissue.

Impressão 3D multimodal de fantasmas para simular tecido biológico

Biomedical optical imaging is playing an important role in diagnosis and treatment of various diseases. However, the accuracy and the reproducibility of ...

Interactive Molecular Model Assembly with 3D Printing

With the growth in accessibility of 3D printing, there has been a growing application of and interest in additive manufacturing processes in chemical laboratories and chemical education. Building on the long and successful history of physical modeling of molecular systems, we present select models along with a protocol to facilitate 3D printing of molecular structures that are able to do more than represent shape and connectivity. Models assembled as described incorporate dynamic aspects and degrees of freedom into saturated hydrocarbon structures. As a representative example, cyclohexane was assembled from parts printed and finished using different thermoplastics, and the resulting models retain their functionality at a variety of scales. The resulting structures show configurational space accessibility consistent with calculations and literature, and versions of these structures can be used as aids to illustrate concepts that are difficult to convey in other ways. This exercise enables us to evaluate successful printing protocols, make practical recommendations for assembly, and outline design principles for physical modeling of molecular systems. The provided structures, procedures, and results provide a foundation for individual manufacture and exploration of molecular structure and dynamics with 3D printing.

Physical modeling of microscopic systems helps obtain insights that are difficult to gain by other means. To facilitate the construction of physical molecular models, we demonstrate how 3D printing can be used to assemble functional macroscopic models that capture qualities of molecular systems in a tactile way.

Conjunto interativo de modelos moleculares com impressão 3D

With the growth in accessibility of 3D printing, there has been a growing application of and interest in additive manufacturing processes in chemical ...

Química

3D Printing and In Situ Surface Modification via Type I Photoinitiated Reversible Addition-Fragmentation Chain Transfer Polymerization

3D printing provides facile access to geometrically complex materials. However, these materials have intrinsically linked bulk and interfacial properties dependent on the chemical composition of the resin. In the current work, 3D printed materials are post-functionalized using the 3D printer hardware via a secondary surface-initiated polymerization process, thus providing independent control over the bulk and interfacial material properties. This process begins with preparing liquid resins, which contain a monofunctional monomer, a crosslinking multifunctional monomer, a photochemically labile species that enables initiation of polymerization, and critically, a thiocarbonylthio compound which facilitates reversible addition-fragmentation chain transfer (RAFT) polymerization. The thiocarbonylthio compound, known commonly as a RAFT agent, mediates the chain growth polymerization process and provides polymeric materials with more homogeneous network structures. The liquid resin is cured in a layer-by-layer fashion using a commercially available digital light processing 3D printer to give three-dimensional materials having spatially controlled geometries. The initial resin is removed and replaced with a new mixture containing functional monomers and photoinitiating species. The 3D printed material is then exposed to light from the 3D printer in the presence of the new functional monomer mixture. This allows photoinduced surface-initiated polymerization to occur from the latent RAFT agent groups on the surface of the 3D printed material. Given the chemical flexibility of both resins, this process allows a wide range of 3D printed materials to be produced with tailorable bulk and interfacial properties.

3D Printing and In Situ Surface Modification via Type I Photoinitiated Reversible Addition-Fragmentation Chain Transfer Polymerization

The present protocol describes the digital light processing-based 3D printing of polymeric materials using type I photoinitiated reversible addition-fragmentation chain transfer polymerization and the subsequent in situ material post-functionalization via surface-mediated polymerization. Photoinduced 3D printing provides materials with independently tailored and spatially controlled bulk and interfacial properties.

Impressão 3D e Modificação da superfície in situ através da polimerização da cadeia de adição reversível do tipo I fotoinitida

3D printing provides facile access to geometrically complex materials. However, these materials have intrinsically linked bulk and interfacial properties ...

Novel Process for 3D Printing Decellularized Matrices

3D bioprinting aims to create custom scaffolds that are biologically active and accommodate the desired size and geometry. A thermoplastic backbone can provide mechanical stability similar to native tissue while biologic agents offer compositional cues to progenitor cells, leading to their migration, proliferation, and differentiation to reconstitute the original tissues/organs1,2. Unfortunately, many 3D printing compatible, bioresorbable polymers (such as polylactic acid, PLA) are printed at temperatures of 210 &#176;C or higher - temperatures that are detrimental to biologics. On the other hand, polycaprolactone (PCL), a different type of polyester, is a bioresorbable, 3D printable material that has a gentler printing temperature of 65 &#176;C. Therefore, it was hypothesized that decellularized extracellular matrix (DM) contained within a thermally protective PLA barrier could be printed within PCL filament and remain in its functional conformation. In this work, osteochondral repair was the application for which the hypothesis was tested. As such, porcine cartilage was decellularized and encapsulated in polylactic acid (PLA) microspheres which were then extruded with polycaprolactone (PCL) into filament to produce 3D constructs via fused deposition modeling. The constructs with or without the microspheres (PLA-DM/PCL and PCL(-), respectively) were evaluated for differences in surface features.

This protocol describes the production of polycaprolactone (PCL) filament with embedded polylactic acid (PLA) microspheres which contain decellularized matrices (DM) for 3D printing of structural tissue engineering constructs.

Novo processo de impressão 3D Decellularized matrizes

3D bioprinting aims to create custom scaffolds that are biologically active and accommodate the desired size and geometry. A thermoplastic backbone can ...

Hidrogéis bioimpressos fotosintonizáveis para sondar as respostas celulares ao enrijecimento da MEC

3D Bioprinting Phototunable Hydrogels to Study Fibroblast Activation

Phototunable hydrogels can transform spatially and temporally in response to light exposure. Incorporating these types of biomaterials in cell-culture platforms and dynamically triggering changes, such as increasing microenvironmental stiffness, enables researchers to model changes in the extracellular matrix (ECM) that occur during fibrotic disease progression. Herein, a method is presented for 3D bioprinting a phototunable hydrogel biomaterial capable of two sequential polymerization reactions within a gelatin support bath. The technique of Freeform Reversible Embedding of Suspended Hydrogels (FRESH) bioprinting was adapted by adjusting the pH of the support bath to facilitate a Michael addition reaction. First, the bioink containing poly(ethylene glycol)-alpha methacrylate (PEG&#945;MA) was reacted off-stoichiometry with a cell-degradable crosslinker to form soft hydrogels. These soft hydrogels were later exposed to photoinitator and light to induce the homopolymerization of unreacted groups and stiffen the hydrogel. This protocol covers hydrogel synthesis, 3D bioprinting, photostiffening, and endpoint characterizations to assess fibroblast activation within 3D structures. The method presented here enables researchers to 3D bioprint a variety of materials that undergo pH-catalyzed polymerization reactions and could be implemented to engineer various models of tissue homeostasis, disease, and repair.

Autor em destaque: Compreendendo doenças pulmonares crônicas usando hidrogéis fototáveis impressos em 3D 

This article describes how to 3D bioprint phototunable hydrogels to study extracellular matrix stiffening and fibroblast activation.

Bioimpressão 3D de hidrogéis fototáveis para estudo da ativação de fibroblastos

Phototunable hydrogels can transform spatially and temporally in response to light exposure. Incorporating these types of biomaterials in cell-culture ...