Tag Archives: University of Wollongong

A new bio-ink, inkjet printers, and printing human cells at Australia’s University of Wollongong

Sometimes I look at my printer and just shake my head at the thought that one day it might produce living cells if the researchers at University of  Wollongong (New South Wales, Australia) have their way. From the Nov. 16, 2012 news item on phys.org,

Researchers have been aware for some time of the potential for using commercially available inkjet printer heads to print living human cells into 3D structures, but design of the actual ink capable of carrying cells through the printer has been a challenge.

The ARC Centre of Excellence for Electromaterials Science at UOW has led a team of scientists including Cameron Ferris, Dr Kerry Gilmore, Dr Stephen Beirne, Dr Donald McCallum, Professor Gordon Wallace and Associate Professor Marc in het Panhuis to develop a new bio-ink that improves the viability of living cells and allows better control of cell positioning through the printing process.

“To date, none of the available inks has been optimised in terms of both printability and cell suspending ability,” according to ACES Associate Researcher Cameron Ferris.

“Our new bio-ink is printable and cell-friendly, preventing cell settling and allowing controlled deposition of cells.”

The Nov. 15, 2012 University of Wollogong news release, which originated the news item, provides some detail about what makes this new bio-ink exciting,

The 2D structures being printed with the bio-ink enables exquisite control over cell distribution and this already presents exciting opportunities to improve drug screening and toxicology testing processes. Building on this, 3D bio-printing, with which patient-specific tissue replacements could be fabricated, is within the grasp of researchers.

The abstract for the researchers’ paper in Biomaterials helped me to build my understanding of this innovation,

Drop-on-demand bioprinting allows the controlled placement of living cells, and will benefit research in the fields of tissue engineering, drug screening and toxicology. We show that a bio-ink based on a novel microgel suspension in a surfactant-containing tissue culture medium can be used to reproducibly print several different cell types, from two different commercially available drop-on-demand printing systems, over long printing periods. The bio-ink maintains a stable cell suspension, preventing the settling and aggregation of cells that usually impedes cell printing, whilst meeting the stringent fluid property requirements needed to enable printing even from many-nozzle commercial inkjet print heads. This innovation in printing technology may pave the way for the biofabrication of multi-cellular structures and functional tissue.

You can access the paper (free access) but you must be registered (it’s free) with RSC (Royal Society of Chemistry) Publishing. Here’s a link and the citation,

Bio-ink for on-demand printing of living cells

Cameron J. Ferris ,  Kerry J. Gilmore ,  Stephen Beirne ,  Donald McCallum ,  Gordon G. Wallace and Marc in het Panhuis

Biomater. Sci., 2013, Advance Article

DOI: 10.1039/C2BM00114D
Received 09 Aug 2012, Accepted 11 Oct 2012
First published on the web 05 Nov 2012

Even more helpful than the abstract and assuming you’re not ready to read the paper is Jennifer Newton’s Nov. 7, 2012 article for the RSC’s Chemistry World,

‘The first bio-inks used in drop-on-demand cell printing were simple salt solutions,’ says Marc in het Panhuis, who was part of the research team at the University of Wollongong. ‘The cells in these inks settled and aggregated quickly, which impeded printing. Cell viability can also be compromised if the salt concentration is too high.’

Other bio-inks include low viscosity biopolymer solutions, which are known to slow cell settling. The team’s bio-ink consists of a biopolymer – gellan gum – and two surfactants in a standard tissue culture medium. The surfactants – Novec FC4430 and Poloxamer 188 – reduce surface tension, allowing optimal inkjet printing, and protect the cells from fluid-mechanical damage.

The cells do not settle and aggregate because the biopolymer creates a structured network of micro-gel particles that keep the cells suspended in the gel. However, the bio-ink remains printable as the network is not rigid and is easily broken down during printing. ‘Our bio-ink allowed us to print multiple cell types over long printing periods without changing print heads or replenishing ink solutions,’ says in het Panhuis.

There are more details in Newton’s article and the image that accompanies it is quite striking.

Aussies, Yanks, Canucks, and Koreans collaborate on artificial muscles

I received a media release (from the University of British Columbia [UBC]) about artificial muscles. I was expecting to see Dr. Hongbin Li’s name as one of the researchers but this is an entirely different kind of artificial muscle. Dr. Li works with artificial proteins to create new biomaterials (my May 5, 2010 posting). This latest work published in Science Express, Oct. 13, 2011,  involves carbon nanotubes and teams from Australia, Canada, Korea, and the US. From the Oct. 13, 2011, UBC media release,

An international team of researchers has invented new artificial muscles strong enough to rotate objects a thousand times their own weight, but with the same flexibility of an elephant’s trunk or octopus limbs.

In a paper published online today on Science Express, the scientists and engineers from the University of British Columbia, the University of Wollongong in Australia, the University of Texas at Dallas and Hanyang University in Korea detail their innovation. The study elaborates on a discovery made by research fellow Javad Foroughi at the University of Wollongong.

Using yarns of carbon nanotubes that are enormously strong, tough and highly flexible, the researchers developed artificial muscles that can rotate 250 degrees per millimetre of muscle length. This is more than a thousand times that of available artificial muscles composed of shape memory alloys, conducting organic polymers or ferroelectrics, a class of materials that can hold both positive and negative electric charges, even in the absence of voltage.

Here’s how the UBC media release recounts the story of these artificial muscles (Aside: The Australians take a different approach; I haven’t seen any material from the University of Texas at Dallas or the University of Hanyang),

The new material was devised at the University of Texas at Dallas and then tested as an artificial muscle in Madden’s [Associate Professor, John Madden, Dept. of Electrical and Computer Engineering] lab at UBC. A chance discovery by collaborators from Wollongong showed the enormous twist developed by the device. Guided by theory at UBC and further experiments in Wollongong and Texas, the team was able to extract considerable torsion and power from the yarns.

The Australians, not unnaturally focus on their own contributions, and, somewhat unexpectedly discuss nanorobots. From the ARC (Australian Research Council) Centre of Excellence for Electromaterials Science (ACES) at the University of Wollongong news release (?) [ETA Oct. 17, 2011: I forgot to include a link to the Australian news item; and here’s a link to the Oct. 16, 2011 Australian news item on Nanowerk] ,

The possibility of a doctor using tiny robots in your body to diagnose and treat medical conditions is one step closer to becoming reality today, with the development of artificial muscles small and strong enough to push the tiny Nanobots along.

Although Nanorobots (Nanobots) have received much attention for the potential medical use in the body, such as cancer fighting, drug delivery and parasite removal, one major hurdle in their development has been the issue of how to propel them along in the bloodstream.

An international collaborative team led by researchers at UOW’s Intelligent Polymer Research Institute, part of the ARC Centre of Excellence for Electromaterials Science (ACES), have developed a new twisting artificial muscle that could be used for propelling nanobots.   The muscles use very tough and highly flexible yarns of carbon nanotubes (nanoscale cylinders of carbon), which are twist-spun into the required form.  When voltage is applied, the yarns rotate up to 600 revolutions per minute, then rotate in reverse when the voltage is changed.

Due to their complexity, conventional motors are very difficult to miniaturise, making them unsuitable for use in nanorobotics.  The twisting artificial muscles, on the other hand, are simple and inexpensive to construct either in very long, or in millimetre lengths.

Interesting, non?

There’s an animation illustrating the nanorobots and the muscles,

In the animated video below, you first see a few bacteria like creatures swimming about. Their rotating flagella are highlighted with some detail of the flagella motor turning the “hook” and “filament” parts of the tail. We next see a similar type of rotating tail produced by a length of carbon nanotube thread that is inside a futuristic microbot. The yarn is immersed in a liquid electrolyte along with another electrode wire. Batteries and an electrical circuit are also inside the bot. When a voltage is applied the yarn partially untwists and turns the filament. Slow discharging of the yarn causes it to re-twist. In this way, we can imagine the micro-bot is propelled along in a series of short spurts.

I think the graphics resemble conception complete with sperm and eggs but I can see the nanorobots too. Here’s your chance to take a look,

ETA Oct. 14, 2011 11:20 am PST: I found a copy of the University of Texas at Dallas news release posted on Oct. 13, 2011 at Nanowerk. No mention of nanobots but if you’re looking for additional technical explanations, this would be good to read.