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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Extrusion Printing Of Ionic-Covalent Entanglement Hydrogels With High Toughness, Shannon Bakarich, Marc In Het Panhuis, Stephen T. Beirne, Gordon G. Wallace, Geoffrey Maxwell Spinks
Extrusion Printing Of Ionic-Covalent Entanglement Hydrogels With High Toughness, Shannon Bakarich, Marc In Het Panhuis, Stephen T. Beirne, Gordon G. Wallace, Geoffrey Maxwell Spinks
Gordon Wallace
Three-dimensional (3D) printing of hydrogels has recently been investigated for use in tissue engineering applications. One major limitation in the use of synthetic hydrogels is their poor mechanical robustness but the development of ‘tough hydrogels’ in conjunction with additive fabrication techniques will accelerate the advancement of many technologies including soft robotics, bionic implants, sensors and controlled release systems. This article demonstrates that ionic–covalent entanglement (ICE) gels can be fabricated through a modified extrusion printing process that facilitates in situ photopolymerisation. The rheological properties of alginate–acrylamide hydrogel precursor solutions were characterised to develop formulations suitable for extrusion printing. A range of …
Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace
Bio-Ink Properties And Printability For Extrusion Printing Living Cells, Johnson H. Y Chung, Sina Naficy, Zhilian Yue, Robert Kapsa, Anita Quigley, Simon E. Moulton, Gordon G. Wallace
Gordon Wallace
Additive biofabrication (3D bioprinting) makes it possible to create scaffolds with precise geometries, control over pore interconnectivity and architectures that are not possible with conventional techniques. Inclusion of cells within the ink to form a “bio-ink” presents the potential to print 3D structures that can be implanted into damaged/diseased tissue to promote highly controlled cell-based regeneration and repair. The properties of an ‘ink’ are defined by its formulation and critically influence the delivery and integrity of structure formed. Importantly, the ink properties need to conform to biological requirements necessary for the cell system that they are intended to support and …
Nanoscale Platinum Printing On Insulating Substrates, C D. O'Connell, M J. Higgins, R P. Sullivan, S S. Jamali, S E. Moulton, G G. Wallace
Nanoscale Platinum Printing On Insulating Substrates, C D. O'Connell, M J. Higgins, R P. Sullivan, S S. Jamali, S E. Moulton, G G. Wallace
Gordon Wallace
The deposition of noble metals on soft and/or flexible substrates is vital for several emerging applications including flexible electronics and the fabrication of soft bionic implants. In this paper, we describe a new strategy for the deposition of platinum electrodes on a range of materials, including insulators and flexible polymers. The strategy is enabled by two principle advances: (1) the introduction of a novel, low temperature strategy for reducing chloroplatinic acid to platinum using nitrogen plasma; (2) the development of a chloroplatinic acid based liquid ink formulation, utilizing ethylene glycol as both ink carrier and reducing agent, for versatile printing …
Fabrication Of Polyaniline-Based Gas Sensors Using Piezoelectric Inkjet And Screen Printing For The Detection Of Hydrogen Sulfide, Karl H. Crowley, Aoife Morrin, Roderick L. Shepherd, Marc In Het Panhuis, Gordon G. Wallace, Malcolm R. Smyth, Anthony J. Killard
Fabrication Of Polyaniline-Based Gas Sensors Using Piezoelectric Inkjet And Screen Printing For The Detection Of Hydrogen Sulfide, Karl H. Crowley, Aoife Morrin, Roderick L. Shepherd, Marc In Het Panhuis, Gordon G. Wallace, Malcolm R. Smyth, Anthony J. Killard
Gordon Wallace
This work describes a fully printable polyaniline-copper (II) chloride sensor for the detection of hydrogen sulfide gas. The sensing device is composed of screen printed silver interdigitated electrode (IDE) on a flexible PET substrate with inkjet printed layers of polyaniline and copper (II) chloride. The sensor is employed as a chemiresistor with changes in measured current being correlated with concentration. On exposure to hydrogen sulfide, 2.5 ppmv (parts per million by volume) is clearly detectable with a linear relationship between measured current and concentration over the 10-100 ppmv region. The detection mechanism is discussed with respect to the hydrogen sulfide …
Printing Nanomaterials Using Non-Contact Printing, Charles Mire, Marc In Het Panhuis, Paul D. Calvert, Gordon G. Wallace
Printing Nanomaterials Using Non-Contact Printing, Charles Mire, Marc In Het Panhuis, Paul D. Calvert, Gordon G. Wallace
Gordon Wallace
We report on the use of inkjet, extrusion, and capillary printing of poly(3,4 ethylenedioxythiophene)/ poly(sodium 4-styrene-sulfonate) (PEDOT/PSS) to create structures that could be used in a flexible, implantable bionic device. Resistance values as low as 250 kΩ are demonstrated, with little deviation under as much as 1.5% strain. The results show PEDOT/PSS can be a suitable material for printed bionic devices.
Fabrication Of Chemical Sensors Using Inkjet Printing And Application To Gas Detection, Karl H. Crowley, Aoife Morrin, Malcolm R. Smyth, Anthony J. Killard, Roderick Shepherd, Marc In Het Panhuis, Gordon G. Wallace
Fabrication Of Chemical Sensors Using Inkjet Printing And Application To Gas Detection, Karl H. Crowley, Aoife Morrin, Malcolm R. Smyth, Anthony J. Killard, Roderick Shepherd, Marc In Het Panhuis, Gordon G. Wallace
Gordon Wallace
This work describes the fabrication of gas sensors using inkjet printing. Sensors were constructed by building up a film of sensing material, such as polyaniline, from aqueous nanoparticulate dispersions. These films were printed over patterned silver interdigitated array designs for the purposes of conductimetric analysis. Unlike screen printing or lithography, inkjet printing does not require stencils or masks, therefore allowing rapid design and prototyping. For this study, polyaniline and modified polyaniline sensors were inkjet printed and assessed for the purposes of gas sensing applications, specifically hydrogen sulfide monitoring.
Inkjet And Extrusion Printing Of Conducting Poly(3,4-Ethylenedioxythiophene) Tracks On And Embedded In Biopolymer Materials, Charles A. Mire, Animesh Agrawal, Gordon G. Wallace, Paul Calvert, Marc In Het Panhuis
Inkjet And Extrusion Printing Of Conducting Poly(3,4-Ethylenedioxythiophene) Tracks On And Embedded In Biopolymer Materials, Charles A. Mire, Animesh Agrawal, Gordon G. Wallace, Paul Calvert, Marc In Het Panhuis
Gordon Wallace
Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in …
Controlled Deposition Of Polymer Carbon Nanotube Composites Through Inkjet Printing, William Small, Fatemeh Masdarolomoor, Gordon G. Wallace, Marc In Het Panhuis
Controlled Deposition Of Polymer Carbon Nanotube Composites Through Inkjet Printing, William Small, Fatemeh Masdarolomoor, Gordon G. Wallace, Marc In Het Panhuis
Gordon Wallace
The controlled deposition of polyaniline carbon nanotube composites by inkjet printing is reported. It is demonstrated that the sheet resistance and transmittance can be expressed in amount of composite and MWNT material deposited. The most efficient way for improving the sheet resistance while keeping the cost in optical transparency to a minimum is by increasing the total amount of material deposited, rather than increasing MWNT loading fraction.
Inkjet Printing Of Self-Assembling Polyelectrolyte Hydrogels, Skander Limen, Donald Mccallum, Gordon G. Wallace, Marc In Het Panhuis, Paul Calvert
Inkjet Printing Of Self-Assembling Polyelectrolyte Hydrogels, Skander Limen, Donald Mccallum, Gordon G. Wallace, Marc In Het Panhuis, Paul Calvert
Gordon Wallace
Inkjet printing of alternate layers of anionic and cationic polyelectrolytes allows organized gels to form with structures similar to those made by layer-by-layer dipping methods but very much faster. Structures of gels formed using slow and fast inkjet printing systems are compared using elemental analysis, swelling and diffusion kinetics as characterization methods. After printing and washing, most sodium or chloride counter-ions are lost from the gel, leaving only the polymer complex. The swelling properties of the printed and washed gel depend on the deposition rate and on the ratio of the two polymers as originally printed.