Mussel fibers inspire polymer gels with strong, reversible, metal coordination bonds
A sudden inspiration led then Ph.D.-student Niels Holten-Andersen to the lab on a Saturday night to test his idea that changing the pH of could cause a fluid polymer dissolved in water to form a gel.
"...I tried just taking some of the polymer that I already had from Professor Messersmith, mixing it with a little bit of metal salt at low pH, and then just dropping sodium hydroxide on it to jump the pH and you got instant gelation," he said. And the gels he made also showed reversible or self-healing properties, just like mussel byssal.
Holten-Andersen is now setting up his own lab at MIT, the Laboratory for Bio-Inspired Interfaces. "What biology can teach us in terms of materials design is how do you control interfaces as an opportunity to control properties," he said.
Mussel Power: Water No Match for Bio-Inspired Self Healing Sticky Gel Video courtesy of the University of Chicago
Ka Yee Lee and Niels Holten-Andersen speak about their research and show a demonstration of the manufacturing of the substance.
New Materials for Biomedical Gels Li studying ionic metal nanoparticles for crosslinking
First-year materials science and engineering graduate student Qiaochu Li, 22, who grew up in China, is looking forward to the opening of MIT Professor Niels Holten-Andersen's Laboratory for Bio-Inspired Interfaces later this spring so he can pursue experimental research into metal ion coordination bonding and self-healing in polymers.
Li has been testing nanoparticles of iron oxide and titanium oxide as bonding agents for dopa groups in the polymer. "We are incorporating our functionality of coordination with metal ions in the mid block of that polymer by synthesizing a polymer chain with a lot of dopamine groups alongside the chain and at the two ends of the chain. We will incorporate another two blocks, which are sensitive to temperature, so the mechanical properties of this material will have response to both pH and temperature. So there are a lot of parameters we can control - the mechanical properties of this material - and there may be potential for applications in biomedical and injectible gels," Li said.
Exploring Self-healing Hydrogels Metal ion coordination reaction plays key role
Materials science and engineering graduate student Scott C. Grindy is looking at the fundamental nature of coordinate cross-links that underlie the self-healing hydrogels developed by Niels Holten-Andersen, who is now the John Chipman Assistant Professor of Materials Science and Engineering at MIT. Specifically, he's trying to understand how changing the chemical dynamics of the metal ion coordination reaction can affect the mechanical response of the gels the group is making.
Grindy also is collaborating with MIT Assistant Professor of Materials Science and Engineering Alfredo Alexander-Katz on molecular dynamics simulations to get a better understanding of the atomic level physics of the gels. Read more.
Eco-evolutionary Feedback Loop
Cheaters lessen yeast survival under stress
While a cooperative yeast colony that thrives by breaking down sucrose can survive with a high proportion of cheaters, or non-producers, such a mixed colony is less able to withstand sudden shock than a population made up purely of cooperators, or producers, researchers at MIT have shown.
In the first laboratory demonstration of an evolutionary-ecological feedback loop in a social, or cooperative, microbial population, MIT Postdoctoral Associate Alvaro Sanchez and MIT Assistant Professor of Physics Jeff Gore found that as the percentage of consumers grew relative to producers, they followed a spiral path toward equilibrium. Read more.
2013 Summer Scholars Announced Congratulations to the 2013 Summer Scholars
SCOTT HO UNIV.OF UTAH, MECH. ENG.
The Materials Processing Center and the Center for Materials Science and Engineering sponsor a Summer Research Internship Program through the NSF REU program. The program started in 1983, and has brought hundreds of the best science and engineering undergraduates in the country to MIT for graduate-level materials research. This year's Summer Scholar Internship Program will run from June 9 - August 10, 2013.
About MPC The goals of the Materials Processing Center are to unite the materials research community at MIT and to enhance Institute-industry interactions. Collaboration on research ventures, technology transfer, continuing education of industry personnel, and communication among industrial and governmental entities are our priorities. The MPC Industry Collegium is a major vehicle for this collaboration. The MPC sponsors seminars and workshops, as well as a summer internship for talented undergraduates from universities across the U.S. We encourage interdisciplinary research collaborations and provide funds management assistance to faculty.
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