Die Autoren möchten die Unterstützung von der New York Capital Region Research Alliance Grants anzuerkennen.

1. Bioprinting Platform Gründung Der Drucker Modifikation wurde auf einem HP Deskjet 500 Thermo-Inkjet-Drucker und HP 51626A schwarz Tintenpatrone basiert. <ol><li> Entfernen Sie die obere Plastikabdeckung des Druckers und vorsichtig lösen das Bedienfeld aus dem Cover. </li><li> Lösen Sie die drei Kabelverbindungen zwischen Drucker oberen Teil und Basis. Entfernen Sie die Drucker oberen Teil von der Basis. </li><li> Auf dem oberen Teil Drucker, entfernen Sie den kleinen Kunststoff-und Gummi Zubehör (Druckkopfreinigung) auf der rechten Seite unter der Tintenpatrone. </li><li> Entfernen Sie die Basis des Papierkassette mit Federn. </li><li> Entfernen Sie die Metallplatte, die die Kunststoffpapierzufuhr-Bar. </li><li> Schneiden Sie den Kunststoff-Papierzufuhr-Bar in der Mitte Zuführungsrad Position mit einer Handsäge oder andere Schneidwerkzeug. </li><li> Entfernen Sie die 2 Papiereinzugsräder nach dem vorherigen Schritt ausgesetzt. Die Kunststoffscheibe ist sehr hart und eine elektronischeSäge wird hilfreich sein. </li><li> Reinigen Sie den Staub und Schmutz mit Pressluft und Ethanol Tücher. </li><li> Bringen Sie den Drucker oberen Teil an der Basis. </li><li> UV die modifizierte Drucker für mindestens 2 Stunden in einer Steril vor der Verwendung zu sterilisieren. </li><li> Schneiden Sie die Kappe eines HP 51626A Tintenpatrone mit einer Handsäge oder andere Schneidwerkzeug. </li><li> Leeren Sie die Tinte und die Filter, die den Boden gut Reservoir der Knorpel bedeckt entfernen. </li><li> Spülen Sie die Patrone gründlich mit fließendem Leitungswasser. </li><li> Ultrasonicate die Kassette in deionisiertem (DI) Wasser für 10 min, um die restliche Tinte zu entfernen. </li><li> Untersuchen Sie die Patrone, um sicherzustellen, dass alle die Tinte entfernt wurde. Spülen oder Spray die Patrone gründlich mit 70% Ethanol für die Sterilisation, gefolgt von DI-Wasser sterilisiert. </li><li> Richten Sie eine langwelligen UV-Lampe über die Druckplattform, um die gleichzeitige Photopolymerisation Kapazität bereitzustellen. </li><li> Messen UV-Intensität an der Druckplattform unter Verwendung eines UV-LichtMeter. Den Abstand zwischen der UV-Lampe und der Druckerplattform, so dass die Intensität an dem Druckgegenstand zwischen 4-8 mW / cm 2 (etwa 25 cm von der Lampe zu der Druckerplattform). </li></ol> 2. Bioink Vorbereitung <ol><li> Monolayer Chondrozyten-Erweiterung <ol><li> Platte 5 Millionen humanen Chondrozyten in jeder T175 Gewebekulturflasche für Zellexpansion in Dulbeccos Modified Eagles Medium (DMEM) mit 10% Kälberserum und 1x Penicillin-Streptomycin-Glutamin (PSG) ergänzt. Kulturzellen bei 37 ° C mit befeuchteter Luft mit 5% CO 2. Ändern Sie das Kulturmedium alle 3 Tage, bis der Kolben beträgt 85% Zusammenfluss. Verwenden Sie Zellen aus der gleichen Passage. </li></ol></li><li> Auflösen PEGDA in PBS auf eine Endkonzentration von 10% w / v. Hinzufügen Photoinitiator I-2959 in einer Endkonzentration von 0,05% w / v. Filter sterilisieren die Lösung. </li><li> Aussetzen kultivierten menschlichen Chondrozyten in dem hergestellten PEGDA Lösung bei 5 x 10 6 Zellen /ml. </li></ol> 3. Knorpelgewebe Printing <ol><li> Schalten Sie den Drucker und Laptop. </li><li> Erstellen Sie ein Druckmuster aus einem festen Kreis mit 4 mm Durchmesser unter Verwendung von Microsoft Word oder Adobe Photoshop. <ol><li> Stellen Sie die Position des Musters und sicherzustellen, dass es genau in die Kunststoffform drucken. </li><li> Berechnen der Anzahl der Drucke, um die gewünschte Dicke der Gerüst erreichen. Für 4 mm in der Höhe, 220 Drucke sind erforderlich, um die gewünschte Gerüst erstellen. </li></ol></li><li> Laden Sie die bioink in die Tintenpatrone. Decken Sie die Patrone mit Aluminiumfolie aus der direkten UV-Exposition während des Druckvorgangs zu schützen. </li><li> Druckbefehl an den Drucker senden. Ziehen Sie den Papiersensor, wenn der Drucker zu drucken beginnt. Der gesamte Druckprozess weniger als 4 min für ein Gerüst mit 4 mm Durchmesser und 4 mm in der Höhe zu nehmen. </li><li> Über gedruckt neocartilage zu einem 24-Well-Platte und fügen 1,5 ml Kulturmedium in jede Vertiefung. </li></ol><ol><li> Inkubieren Sie die gedruckte neocartilage in LIVE / DEAD Lebensfähigkeit / Zytotoxizität Arbeitslösung bei Raumtemperatur für 15 min im Dunkeln. </li><li> Schneiden Sie die Zelle beladene Hydrogel in der Mitte und nehmen Fluoreszenzbilder von den Schneidbereich. </li><li> Graf Live-(grün) und toten (rot) Zellen durch einen verblindeten Beobachter bei fünf zufällig aufgenommenen Bilder. Lebensfähigkeit der Zellen zu berechnen, indem die Anzahl von lebenden Zellen durch die Gesamtzahl an lebenden und toten Zellen. </li></ol>

<ol>
	<li>Cui, X., Boland, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+microvasculature+fabrication+using+thermal+inkjet+printing+technology.">Human microvasculature fabrication using thermal inkjet printing technology.</a> Biomaterials. 30, 6221-6227 (2009).</li><li>Cui, X., Breitenkamp, K., Finn, M. G., Lotz, M., D'Lima, D. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+human+cartilage+repair+using+three-dimensional+bioprinting+technology.">Direct human cartilage repair using three-dimensional bioprinting technology.</a> Tissue Eng Part A. 18, 1304-1312 (2012).</li><li>Cui, X., Breitenkamp, K., Lotz, M., D'Lima, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synergistic+action+of+fibroblast+growth+factor-2+and+transforming+growth+factor-beta1+enhances+bioprinted+human+neocartilage+formation.">Synergistic action of fibroblast growth factor-2 and transforming growth factor-beta1 enhances bioprinted human neocartilage formation.</a> Biotechnol. Bioeng. 109, 2357-2368 (2012).</li><li>Cui, X., Breitenkamp, K., Finn, M. G., Lotz, M., Colwell, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+human+cartilage+repair+using+thermal+inkjet+printing+technology.">Direct human cartilage repair using thermal inkjet printing technology.</a> Osteoarthritis and Cartilage. 19, (2011).</li><li>Cui, X., Boland, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+deposition+of+human+microvascular+endothelial+cells+and+biomaterials+for+human+microvasculature+fabrication+using+inkjet+printing.">Simultaneous deposition of human microvascular endothelial cells and biomaterials for human microvasculature fabrication using inkjet printing.</a> NIP24/digital Fabrication 2008: 24th International Conference on Digital Printing Technologies, Technical Program and Proceedings. 24, 480-483 (2008).</li><li>Cui, X., Dean, D., Ruggeri, Z. M., Boland, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+damage+evaluation+of+thermal+inkjet+printed+Chinese+hamster+ovary+cells.">Cell damage evaluation of thermal inkjet printed Chinese hamster ovary cells.</a> Biotechnol. Bioeng. 106, 963-969 (2010).</li><li>Cui, X., Hasegawa, A., Lotz, M., D'Lima, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structured+three-dimensional+co-culture+of+mesenchymal+stem+cells+with+meniscus+cells+promotes+meniscal+phenotype+without+hypertrophy.">Structured three-dimensional co-culture of mesenchymal stem cells with meniscus cells promotes meniscal phenotype without hypertrophy.</a> Biotechnol. Bioeng. 109, 2369-2380 (2012).</li><li>Cui, X., Gao, G., Qiu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accelerated+myotube+formation+using+bioprinting+technology+for+biosensor+applications.">Accelerated myotube formation using bioprinting technology for biosensor applications.</a> Biotechnol. Lett. 35, 315-321 (2013).</li><li>Cui, X., Boland, T., D'Lima, D. D., Lotz, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+inkjet+printing+in+tissue+engineering+and+regenerative+medicine.">Thermal inkjet printing in tissue engineering and regenerative medicine.</a> Recent Pat Drug Deliv Formul. 6, 149-155 (2012).</li><li>Bryant, S. J., Anseth, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogel+properties+influence+ECM+production+by+chondrocytes+photoencapsulated+in+poly(ethylene+glycol)+hydrogels.">Hydrogel properties influence ECM production by chondrocytes photoencapsulated in poly(ethylene glycol) hydrogels.</a> Journal of Biomedical Materials Research. 59, 63-72 (2002).</li><li>Elisseeff, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photoencapsulation+of+chondrocytes+in+poly(ethylene+oxide)-based+semi-interpenetrating+networks.">Photoencapsulation of chondrocytes in poly(ethylene oxide)-based semi-interpenetrating networks.</a> Journal of Biomedical Materials Research. 51, 164-171 (2000).</li><li>Buskirk, W. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+A+High-Resolution+Thermal+Inkjet+Printhead.">Development of A High-Resolution Thermal Inkjet Printhead.</a> Hewlett-Packard Journal. 39, 55-61 (1988).</li><li>Harmon, J. P., Widder, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrating+the+Printhead+Into+the+HP+Deskjet+Printer.">Integrating the Printhead Into the HP Deskjet Printer.</a> Hewlett-Packard Journal. 39, 62-66 (1988).</li><li>Kim, T. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+model+for+cartilage+tissue+engineering+to+regenerate+the+zonal+organization+of+articular+cartilage.">Experimental model for cartilage tissue engineering to regenerate the zonal organization of articular cartilage.</a> Osteoarthritis and Cartilage. 11, 653-664 (2003).</li><li>Sharma, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Designing+zonal+organization+into+tissue-engineered+cartilage.">Designing zonal organization into tissue-engineered cartilage.</a> Tissue Engineering. 13, 405-414 (2007).</li><li>Cohen, D. L., Lipton, J. I., Bonassar, L. J., Lipson, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Additive+manufacturing+for+in+situ+repair+of+osteochondral+defects.">Additive manufacturing for in situ repair of osteochondral defects.</a> Biofabrication. 2, (2010).</li></ol>

Die Autoren haben kein finanzielles Interesse an dieser Studie.

Diese 3D-Bioprinting System mit gleichzeitiger Photopolymerisation Kapazität bietet eine deutlich größere Druckauflösung als die besten zuvor berichtet Verfahren der In-situ Druck von osteochondralen Defekten mit Spritze extrudiert eine zelluläre Alginat-Hydrogel-16. Höhere Druckauflösung ist für die Knorpelgewebetechnik besonders wichtig, um die anatomischen Knorpel zonale Organisation wiederherzustellen. Gleichzeitige Photopolymerisation in Schicht-für-Schicht-Anordnung ist entscheidend, u...

Basierend auf Thermo-Inkjet-Druck Bioprinting ist eine der aussichtsreichsten Schlüsseltechnologien auf dem Gebiet des Tissue Engineering und der regenerativen Medizin. Mit Digitalsteuerung und einen hohen Durchsatz Druckköpfe Zellen, Gerüste und Wachstumsfaktoren kann präzise auf die gewünschte zweidimensionale (2D) aufgebracht werden und dreidimensionale (3D-) Positionen schnell. Viele erfolgreiche Anwendungen wurden mit dieser Technologie in Tissue Engineering und der regenerativen Medizin 9.1 erreicht. In dieser Arbeit wurde ein Bioprinting Plattform mit einer modifizierten Hewlett-Packard (HP) Deskjet 500 thermische Tintenstrahldrucker und einer gleichzeitigen Photopolymerisation System. Synthetische Hydrogele aus Poly (Ethylenglycol) (PEG) formuliert haben, die Fähigkeit zur Aufrechterhaltung und Förderung der Lebensfähigkeit von Chondrozyten chondrogene ECM Produktion 10,11 gezeigt. Darüber hinaus ist photovernetzbares PEG in Wasser mit niedriger Viskosität, die es ideal für die gleichzeitige Polyme macht sehr gut löslichrization während der 3D-Bioprinting. In diesem Papier, humanen Chondrozyten in Poly (Ethylen) Glykoldiacrylat (PEGDA; 3.400 MW) suspendiert wurden gedruckt, um genau neocartilage Schicht-für-Schicht mit 1.400 dpi Auflösung in 3D zu konstruieren. Homogene Verteilung der abgeschiedenen Zellen in einem 3D-Gerüst beobachtet, die Knorpelgewebe mit ausgezeichneten mechanischen Eigenschaften und verbesserter ECM Produktion erzeugt. Hingegen in der manuellen Fertigung der Zellen am Boden des Gels statt ihrer anfänglich abgeschiedenen Positionen aufgrund langsamer Gerüst Polymerisation, die zu inhomogenen Knorpelbildung nach der Kultur akkumuliert 2,3 führte.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">HP Deskjet 500 thermal inkjet printer</td>
			<td style="width:221px;">Hewlett-Packard</td>
			<td style="width:195px;">C2106a</td>
			<td style="width:433px;">Discontinued. Purchased refurbished from internet vendor.</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">HP black ink cartridge</td>
			<td style="width:221px;">Hewlett-Packard</td>
			<td style="width:195px;">51626a</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Ultraviolet lamp</td>
			<td style="width:221px;">UVP</td>
			<td style="width:195px;">B-100AP</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">UV light meter</td>
			<td style="width:221px;">General Tools</td>
			<td style="width:195px;">UV513AB</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Zeiss LSM 510 laser scanning microscope</td>
			<td style="width:221px;">Carl Zeiss</td>
			<td style="width:195px;">LSM 510</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Dulbeccos Modified Eagles Medium (DMEM)</td>
			<td style="width:221px;">Mediatech</td>
			<td style="width:195px;">10-013</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Penicillin-streptomycin-glutamine (PSG)</td>
			<td style="width:221px;">Invitrogen</td>
			<td style="width:195px;">10378-016</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Accutase cell dissociation reagent</td>
			<td style="width:221px;">Invitrogen</td>
			<td style="width:195px;">A11105-01</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Phosphate buffered saline (PBS)</td>
			<td style="width:221px;">Invitrogen</td>
			<td style="width:195px;">10010-023</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Live/Dead viability/cytotoxicity Kit</td>
			<td style="width:221px;">Invitrogen</td>
			<td style="width:195px;">L-3224</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Poly(ethylene glycol) diacrylate (PEGDA)</td>
			<td style="width:221px;">Glycosan Biosystems</td>
			<td style="width:195px;">GS700</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Irgacure 2959</td>
			<td style="width:221px;">Ciba Specialty Chemicals</td>
			<td style="width:195px;">I-2959</td>
			<td style="width:433px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:357px;">Human articular chondrocytes</td>
			<td style="width:221px;">Lonza</td>
			<td style="width:195px;">CC-2550</td>
			<td style="width:433px;"></td>
		</tr>
	</tbody>
</table>

human cartilage tissue fabrication using three-dimensional inkjet printing technology

Bioprinting, die auf thermische Tintenstrahldruck basiert, ist einer der attraktivsten Technologien auf dem Gebiet des Tissue Engineering und der regenerativen Medizin. Mit digitalen Kontrollzellen, Gerüste und Wachstumsfaktoren genau auf die gewünschte zweidimensionale (2D) aufgebracht werden und dreidimensionale (3D) Stellen schnell. Daher ist diese Technologie ein idealer Ansatz, um Gewebe imitiert ihre Mutter anatomischen Strukturen herzustellen. Um mit nativen Knorpel zonale Organisation, Zusammensetzung der extrazellulären Matrix (ECM), und die mechanischen Eigenschaften zu konstruieren, entwickelten wir eine Bioprinting Plattform mit einem handelsüblichen Tintenstrahldrucker mit gleichzeitiger Photopolymerisation Lage für 3D-Knorpel Tissue Engineering. Menschlichen Chondrozyten in Poly (ethylenglykol) diacrylat (PEGDA) suspendiert wurden für 3D neocartilage Konstruktion über Schicht-für-Schicht-Anordnung gedruckt. Die gedruckten Zellen wurden bei ihrer ursprünglichen hinterlegt Positionen fixiert, durch die Surro unterstütztunding Gerüst gleichzeitige Photopolymerisation. Die mechanischen Eigenschaften des Gewebes gedruckt waren ähnlich dem nativen Knorpel. Im Vergleich zu herkömmlichen Herstellungsgewebe, die längere UV-Belichtung erfordert, die Lebensfähigkeit der Zellen bei gleichzeitiger gedruckt Photopolymerisation war signifikant höher. Gedruckt neocartilage zeigte eine hervorragende Glykosaminoglykan (GAG) und Kollagen-Typ-II-Produktion, die im Einklang mit Gen-Expression war. Daher ist diese ideale Plattform für die genaue Zellverteilung und Anordnung zur anatomischen Tissue Engineering.

Die modifizierte Thermo-Inkjet-Drucker der Lage war, für Zell-und Gerüst-Abscheidung bei hohem Durchsatz und exzellente Lebensfähigkeit der Zellen. Kombination mit gleichzeitiger Photopolymerisation und empfindlichen Biomaterialien, ist diese Technologie in der Lage, um die Zellen und andere Druck Substanzen zu den anfänglich abgeschiedenen Orten zu fixieren. Gemäß den Eigenschaften des modifizierten thermischer Tintenstrahldrucker der 2D Druckauflösung von 300 dpi mit einer einzigen Tintentropfenvolumen von 130 ...

Watch this Scientific Journal Video about Human Cartilage Tissue Fabrication Using Three-dimensional Inkjet Printing Technology at JoVE.com

Human Cartilage Tissue Fabrication Using Three-dimensional Inkjet Printing Technology

Die in diesem Beitrag beschriebenen Methoden zeigen, wie ein Handels Tintenstrahldrucker in eine Bioprinter mit gleichzeitiger UV-Polymerisation zu konvertieren. Der Drucker ist in der Lage, 3D-Konstruktion von Gewebestruktur mit Zellen und Biomaterialien. Die Studie zeigte hier konstruierte eine 3D neocartilage.

Menschliches Knorpelgewebe Herstellung unter Verwendung von dreidimensionalen Inkjet-Drucktechnologie

Bioprinting, which is based on thermal inkjet printing, is one of the most attractive enabling technologies in the field of tissue engineering and ...

human-cartilage-tissue-fabrication-using-three-dimensional-inkjet

Research

JoVE Journal

Bioengineering

15.7K Aufrufe.  Rensselaer Polytechnic Institute.  Die in diesem Beitrag beschriebenen Methoden zeigen, wie ein Handels Tintenstrahldrucker in eine Bioprinter mit gleichzeitiger UV-Polymerisation zu konvertieren. Der Drucker ist in der Lage, 3D-Konstruktion von Gewebestruktur mit Zellen und Biomaterialien. Die Studie zeigte hier konstruierte eine 3D neocartilage. 

Serie: Human Cartilage Tissue Fabrication Using Three-dimensional Inkjet Printing Technology

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.

Planar-und Drei-Dimensional Printing von Leitfähige Druckfarben

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

Forschung

Biotechnik

Generation of a Three-dimensional Full Thickness Skin Equivalent and Automated Wounding

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models reflect the human wound situation better than animal models. Although two-dimensional models are widely used to investigate processes such as cellular migration and proliferation, models that are more complex are required to gain a deeper knowledge about wound healing. Besides a suitable model system, the generation of precise and reproducible wounds is crucial to ensure comparable results between different test runs. In this study, the generation of a three-dimensional full thickness skin equivalent to study wound healing is shown. The dermal part of the models is comprised of human dermal fibroblast embedded in a rat-tail collagen type I hydrogel. Following the inoculation with human epidermal keratinocytes and consequent culture at the air-liquid interface, a multilayered epidermis is formed on top of the models. To study the wound healing process, we additionally developed an automated wounding device, which generates standardized wounds in a sterile atmosphere.

The goal of this protocol is to build up a three-dimensional full thickness skin equivalent, which resembles natural skin. With a specifically constructed automated wounding device, precise and reproducible wounds can be generated under maintenance of sterility.

Erzeugung eines dreidimensionalen Vollhaut Equivalent und automatisierte Verwundung

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models ...

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.

Dreidimensionale Biomimetic Technologie: Neuartige Biorubber Erzeugt definierte Mikro- und Makro-Skala Architekturen in Collagen Hydrogele

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

Fabrication of Inverted Colloidal Crystal Poly(ethylene glycol) Scaffold: A Three-dimensional Cell Culture Platform for Liver Tissue Engineering

The ability to maintain hepatocyte function in vitro, for the purpose of testing xenobiotics&#39; cytotoxicity, studying virus infection and developing drugs targeted at the liver, requires a platform in which cells receive proper biochemical and mechanical cues. Recent liver tissue engineering systems have employed three-dimensional (3D) scaffolds composed of synthetic or natural hydrogels, given their high water retention and their ability to provide the mechanical stimuli needed by the cells. There has been growing interest in the inverted colloidal crystal (ICC) scaffold, a recent development, which allows high spatial organization, homotypic and heterotypic cell interaction, as well as cell-extracellular matrix (ECM) interaction. Herein, we describe a protocol to fabricate the ICC scaffold using poly (ethylene glycol) diacrylate (PEGDA) and the particle leaching method. Briefly, a lattice is made from microsphere particles, after which a pre-polymer solution is added, properly polymerized, and the particles are then removed, or leached, using an organic solvent (e.g., tetrahydrofuran). The dissolution of the lattice results in a highly porous scaffold with controlled pore sizes and interconnectivities that allow media to reach cells more easily. This unique structure allows high surface area for the cells to adhere to as well as easy communication between pores, and the ability to coat the PEGDA ICC scaffold with proteins also shows a marked effect on cell performance. We analyze the morphology of the scaffold as well as the hepatocarcinoma cell (Huh-7.5) behavior in terms of viability and function to explore the effect of ICC structure and ECM coatings. Overall, this paper provides a detailed protocol of an emerging scaffold that has wide applications in tissue engineering, especially liver tissue engineering.

Fabrication of Inverted Colloidal Crystal Polyethylene glycol Scaffold: A Three-dimensional Cell Culture Platform for Liver Tissue Engineering

This manuscript presents a detailed protocol for the fabrication of an emerging three-dimensional hepatocyte culture platform, the inverted colloidal crystal scaffold, and the concomitant techniques to assess hepatocyte behavior. The size-controllable pores, interconnectivity and ability to conjugate extracellular matrix proteins to the poly(ethylene glycol) (PEG) scaffold enhance Huh-7.5 cell performance.

Die Herstellung von Inverted Kolloid-Kristallen Poly (Ethylenglycol) Scaffold: Eine dreidimensionale Zellkultur-Plattform für Leber-Tissue Engineering

The ability to maintain hepatocyte function in vitro, for the purpose of testing xenobiotics&#39; cytotoxicity, studying virus infection and developing ...

Fabrication of Three-dimensional Paper-based Microfluidic Devices for Immunoassays

Paper wicks fluids autonomously due to capillary action. By patterning paper with hydrophobic barriers, the transport of fluids can be controlled and directed within a layer of paper. Moreover, stacking multiple layers of patterned paper creates sophisticated three-dimensional microfluidic networks that can support the development of analytical and bioanalytical assays. Paper-based microfluidic devices are inexpensive, portable, easy to use, and require no external equipment to operate. As a result, they hold great promise as a platform for point-of-care diagnostics. In order to properly evaluate the utility and analytical performance of paper-based devices, suitable methods must be developed to ensure their manufacture is reproducible and at a scale that is appropriate for laboratory settings. In this manuscript, a method to fabricate a general device architecture that can be used for paper-based immunoassays is described. We use a form of additive manufacturing (multi-layer lamination) to prepare devices that comprise multiple layers of patterned paper and patterned adhesive. In addition to demonstrating the proper use of these three-dimensional paper-based microfluidic devices with an immunoassay for human chorionic gonadotropin (hCG), errors in the manufacturing process that may result in device failures are discussed. We expect this approach to manufacturing paper-based devices will find broad utility in the development of analytical applications designed specifically for limited-resource settings.

We detail a method to fabricate three-dimensional paper-based microfluidic devices for use in the development of immunoassays. Our approach to device assembly is a type of multilayer, additive manufacturing. We demonstrate a sandwich immunoassay to provide representative results for these types of paper-based devices.

Herstellung von dreidimensionalen Papierbasis Microfluidic Devices für Immunoassays

Paper wicks fluids autonomously due to capillary action. By patterning paper with hydrophobic barriers, the transport of fluids can be controlled and ...

Melt Electrospinning Writing of Three-dimensional Poly(&#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology with great potential for biomedical applications. The technique facilitates the direct deposition of biocompatible polymer fibers to fabricate well-ordered scaffolds in the sub-micron to micro scale range. The establishment of a stable, viscoelastic, polymer jet between a spinneret and a collector is achieved using an applied voltage and can be direct-written. A significant benefit of a typical porous scaffold is a high surface-to-volume ratio which provides increased effective adhesion sites for cell attachment and growth. Controlling the printing process by fine-tuning the system parameters enables high reproducibility in the quality of the printed scaffolds. It also provides a flexible manufacturing platform for users to tailor the morphological structures of the scaffolds to their specific requirements. For this purpose, we present a protocol to obtain different fiber diameters using melt electrospinning writing (MEW) with a guided amendment of the parameters, including flow rate, voltage and collection speed. Furthermore, we demonstrate how to optimize the jet, discuss often experienced technical challenges, explain troubleshooting techniques and showcase a wide range of printable scaffold architectures.

Melt Electrospinning Writing of Three-dimensional Poly(&amp;#949;-caprolactone) Scaffolds with Controllable Morphologies for Tissue Engineering Applications

This protocol serves as a comprehensive guideline to fabricate scaffolds via electrospinning with polymer melts in a direct writing mode. We systematically outline the process and define the appropriate parameter settings for achieving targeted scaffold architectures.

Elektrospinnen Schreiben von dreidimensionalen Poly(ε-caprolactone) Gerüste mit steuerbaren Morphologien für Tissue Engineering Anwendungen zu schmelzen

This tutorial reflects on the fundamental principles and guidelines for electrospinning writing with polymer melts, an additive manufacturing technology ...

Culturing Mammalian Cells in Three-dimensional Peptide Scaffolds

A useful technique for culturing cells in a self-assembling nanofiber three-dimensional (3D) scaffold is described. This culture system recreates an environment that closely mimics the structural features of non-polarized tissue. Furthermore, the particular intrinsic nanofiber structure of the scaffold makes it transparent to visual light, which allows for easy visualization of the sample under microscopy. This advantage was largely used to study cell migration, organization, proliferation, and differentiation and thus any development of their particular cellular function by staining with specific dyes or probes. Furthermore, in this work, we describe the good performance of this system to easily study the redifferentiation of expanded human articular chondrocytes into cartilaginous tissue. Cells were encapsulated into self-assembling peptide scaffolds and cultured under specific conditions to promote chondrogenesis. Three-dimensional cultures showed good viability during the 4 weeks of the experiment. As expected, samples cultured with chondrogenic inducers (compared to non-induced controls) stained strongly positive for toluidine blue (which stains glycosaminoglycans (GAGs) that are highly present in cartilage extracellular matrix) and expressed specific molecular markers, including collagen type I, II and X, according to Western Blot analysis. This protocol is easy to perform and can be used at research laboratories, industries and for educational purposes in laboratory courses.

Here, we present a protocol to obtain 3D-culture systems in self-assembling peptide scaffolds to promote the differentiation of dedifferentiated human articular chondrocytes into cartilage-like tissue.

Kultivierung von Säugerzellen in dreidimensionale Peptid Gerüste

A useful technique for culturing cells in a self-assembling nanofiber three-dimensional (3D) scaffold is described. This culture system recreates an ...

Three-dimensional Printing of Thermoplastic Materials to Create Automated Syringe Pumps with Feedback Control for Microfluidic Applications

Microfluidics has become a critical tool in research across the biological, chemical, and physical sciences. One important component of microfluidic experimentation is a stable fluid handling system capable of accurately providing an inlet flow rate or inlet pressure. Here, we have developed a syringe pump system capable of controlling and regulating the inlet fluid pressure delivered to a microfluidic device. This system was designed using low-cost materials and additive manufacturing principles, leveraging three-dimensional (3D) printing of thermoplastic materials and off-the-shelf components whenever possible. This system is composed of three main components: a syringe pump, a pressure transducer, and a programmable microcontroller. Within this paper, we detail a set of protocols for fabricating, assembling, and programming this syringe pump system. Furthermore, we have included representative results that demonstrate high-fidelity, feedback control of inlet pressure using this system. We expect this protocol will allow researchers to fabricate low-cost syringe pump systems, lowering the entry barrier for the use of microfluidics in biomedical, chemical, and materials research.

Here we present a protocol to construct a pressure-controlled syringe pump to be used in microfluidic applications. This syringe pump is made from an&#160;additively manufactured body, off-the-shelf hardware, and open-source electronics. The resulting system is low-cost, straightforward to build, and delivers well-regulated fluid flow to enable rapid microfluidic research.

Dreidimensionaler Druck von thermoplastischen Materialien erstellen automatisiert Spritzenpumpen mit Feedback-Kontrolle für mikrofluidische Anwendungen

Microfluidics has become a critical tool in research across the biological, chemical, and physical sciences. One important component of microfluidic ...

Fabrication of Decellularized Cartilage-derived Matrix Scaffolds

Osteochondral defects lack sufficient intrinsic repair capacity to regenerate functionally sound bone and cartilage tissue. To this extent, cartilage research has focused on the development of regenerative scaffolds. This article describes the development of scaffolds that are completely derived from natural cartilage extracellular matrix, coming from an equine donor. Potential applications of the scaffolds include producing allografts for cartilage repair, serving as a scaffold for osteochondral tissue engineering, and providing in vitro models to study tissue formation. By decellularizing the tissue, the donor cells are removed, but many of the natural bioactive cues are thought to be retained. The main advantage of using such a natural scaffold in comparison to a synthetically produced scaffold is that no further functionalization of polymers is required to drive osteochondral tissue regeneration. The cartilage-derived matrix scaffolds can be used for bone and cartilage tissue regeneration in both in vivo and in vitro settings.

Decellularized cartilage-derived scaffolds can be used as a scaffold to guide cartilage repair and as a means to regenerate osteochondral tissue. This paper describes the decellularization process in detail and provides suggestions to use these scaffolds in in vitro settings.

Herstellung von Decellularized Knorpel abgeleitet Matrix Gerüste

Osteochondral defects lack sufficient intrinsic repair capacity to regenerate functionally sound bone and cartilage tissue. To this extent, cartilage ...

Pancreatic Tissue-Derived Extracellular Matrix Bioink for Printing 3D Cell-Laden Pancreatic Tissue Constructs

The transplantation of pancreatic islets is a promising treatment for patients who suffer from type 1 diabetes accompanied by hypoglycemia and secondary complications. However, islet transplantation still has several limitations such as the low viability of transplanted islets due to poor islet engraftment and hostile environments. In addition, the insulin-producing cells differentiated from human pluripotent stem cells have limited ability to secrete sufficient hormones that can regulate the blood glucose level; therefore, improving the maturation by culturing cells with proper microenvironmental cues is strongly required. In this article, we elucidate protocols for preparing a pancreatic tissue-derived decellularized extracellular matrix (pdECM) bioink to provide a beneficial microenvironment that can increase glucose sensitivity of pancreatic islets, followed by describing the processes for generating 3D pancreatic tissue constructs using a microextrusion-based bioprinting technique.

Decellularized extracellular matrix (dECM) can provide suitable microenvironmental cues to recapitulate the inherent functions of target tissues in an engineered construct. This article elucidates the protocols for the decellularization of pancreatic tissue, evaluation of pancreatic tissue-derived dECM bioink, and generation of 3D pancreatic tissue constructs using a bioprinting technique.

Pankreasgewebe-abgeleitete extrazelluläre Matrix Bioink für den Druck 3D-Zell-Laden Pankreasgewebe Konstrukte

The transplantation of pancreatic islets is a promising treatment for patients who suffer from type 1 diabetes accompanied by hypoglycemia and secondary ...