Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers develop 3-D-printed biomaterials that degrade on demand

08.09.2017

Brown University engineers have demonstrated a technique for making 3-D-printed biomaterials that can degrade on demand, which can be useful in making intricately patterned microfluidic devices or in making cell cultures than can change dynamically during experiments.

"It's a bit like Legos," said Ian Wong, an assistant professor in Brown's School of Engineering and co-author of the research. "We can attach polymers together to build 3-D structures, and then gently detach them again under biocompatible conditions."


Brown researchers have found a way to 3-D print intricate temporary microstructures that can be degraded on demand using a biocompatible chemical trigger. The technique could be useful could be useful in fabricating microfluidic devices, creating biomaterials that respond dynamically to stimuli and in patterning artificial tissue.

Credit: Wong Lab / Brown University

The research is published in the journal Lab on a Chip.

The Brown team made their new degradable structures using a type of 3-D printing called stereolithography. The technique uses an ultraviolet laser controlled by a computer-aided design system to trace patterns across the surface of a photoactive polymer solution. The light causes the polymers to link together, forming solid 3-D structures from the solution. The tracing process is repeated until an entire object is built from the bottom up.

Stereolithographic printing usually uses photoactive polymers that link together with covalent bonds, which are strong but irreversible. For this new study, Wong and his colleagues wanted to try creating structures with potentially reversible ionic bonds, which had never been done before using light-based 3-D printing. To do it, the researchers made precursor solutions with sodium alginate, a compound derived from seaweed that is known to be capable of ionic crosslinking.

"The idea is that the attachments between polymers should come apart when the ions are removed, which we can do by adding a chelating agent that grabs all the ions," Wong said. "This way we can pattern transient structures that dissolve away when we want them to."

The researchers showed that alginate could indeed be used in stereolithography. And by using different combinations of ionic salts -- magnesium, barium and calcium -- they could create structures with varying stiffness, which could then be dissolved away at varying rates.

The research also showed several ways in such temporary alginate structures could be useful.

"It's a helpful tool for fabrication," said Thomas M. Valentin, a Ph.D. student in Wong's lab at Brown and the study's lead author. The researchers showed that they could use alginate as a template for making lab-on-a-chip devices with complex microfluidic channels.

"We can print the shape of the channel using alginate, then print a permanent structure around it using a second biomaterial," Valentin said. "Then we simply dissolve away the alginate and we have a hollow channel. We don't have to do any cutting or complex assembly."

The researchers also showed that degradable alginate structures are useful for making dynamic environments for experiments with live cells. They performed a series of experiments with alginate barriers surrounded by human mammary cells, observing how the cells migrate when the barrier is dissolved away. These kinds of experiments can be useful in investigating wound-healing processes or the migration of cells in cancer.

The experiments showed that neither the alginate barrier nor the chelating agent used to dissolve it away had any appreciable toxicity to the cells. That suggests that degradable alginate barriers are a promising option for such experiments.

The biocompatibility of the alginate is promising for additional future applications, including in making scaffolds for artificial tissue and organs, the researchers say.

"We can start to think about using this in artificial tissues where you might want channels running through it that mimic blood vessels," Wong said. "We could potentially template that vasculature using alginate and then dissolve it away like we did for the microfluidic channels."

The researchers plan to continue experimenting with their alginate structures, looking for ways to fine-tune their strength and stiffness properties, as well as the pace of degradation.

###

In addition to Valentin and Wong, co-authors on the paper were Susan Leggett, Po-Yen Chen, Jaskiranjeet Sodhi, Lauren Stephens, Hayley McClintock and Jea Yun Sim. The research was supported by the Department of Education (P200A150037), National Institutes of Health (5T32ES007272-24), Brown's Hibbitt Postdoctoral Fellowship and the Center for Cancer Research and Development at Rhode Island Hospital (1P30GM110759-O1A1).

Media Contact

Kevin Stacey
kevin_stacey@brown.edu
401-863-3766

 @brownuniversity

http://news.brown.edu/ 

Kevin Stacey | EurekAlert!

Further reports about: 3-D structures artificial biomaterials microfluidic stiffness

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: High-pressure scientists in Bayreuth discover promising material for information technology

Researchers at the University of Bayreuth have discovered an unusual material: When cooled down to two degrees Celsius, its crystal structure and electronic properties change abruptly and significantly. In this new state, the distances between iron atoms can be tailored with the help of light beams. This opens up intriguing possibilities for application in the field of information technology. The scientists have presented their discovery in the journal "Angewandte Chemie - International Edition". The new findings are the result of close cooperation with partnering facilities in Augsburg, Dresden, Hamburg, and Moscow.

The material is an unusual form of iron oxide with the formula Fe₅O₆. The researchers produced it at a pressure of 15 gigapascals in a high-pressure laboratory...

Im Focus: From China to the South Pole: Joining forces to solve the neutrino mass puzzle

Study by Mainz physicists indicates that the next generation of neutrino experiments may well find the answer to one of the most pressing issues in neutrino physics

Among the most exciting challenges in modern physics is the identification of the neutrino mass ordering. Physicists from the Cluster of Excellence PRISMA+ at...

Im Focus: Therapies without drugs

Fraunhofer researchers are investigating the potential of microimplants to stimulate nerve cells and treat chronic conditions like asthma, diabetes, or Parkinson’s disease. Find out what makes this form of treatment so appealing and which challenges the researchers still have to master.

A study by the Robert Koch Institute has found that one in four women will suffer from weak bladders at some point in their lives. Treatments of this condition...

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Bacteria loop-the-loop

27.02.2020 | Life Sciences

Project on microorganisms: Saci, the bio-factory

27.02.2020 | Life Sciences

New method converts carbon dioxide to methane at low temperatures

27.02.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>