MIT Researchers Develop ‘Living Materials’

My friends from down the road at MIT have just announced that they have managed to make bacterial cells produce biofilms that can act as “living materials.”

In the press release that you can read here, the researcher state that they can use the man-made living materials to conduct light or generate energy. Like live cells, the living materials are environmentally responsive, but also have all the traits of non-living particles.

To quote senior author Timothy Lu, an MIT assistant professor of electrical engineering and biological engineering, “Our idea is to put the living and the non-living worlds together to make hybrid materials that have living cells in them and are functional. It’s an interesting way of thinking about materials synthesis, which is very different from what people do now, which is usually a top-down approach.”

Lu said the practical, everyday uses for the research would be self-healing materials, solar cells, diagnostic sensors and more.

The paper was published in the journal Nature Materials.

The researchers used mostly the E. coli bacteria for its naturally produced curli fibers biofilm. Curli fibers are proteins that stick E. coli to various surfaces, which is probably one of the things we don’t generally like about it, but they are useful for the project because they help retain non-living particles.

e-coli

E-coli

The research team also demonstrated how the cells even appeared to communicate with each other, designing living materials that could coordinate the stimulation of each cell to control the composition of the biofilms.

To quote Prof Lu again “It’s a really simple system but what happens over time is you get curli that’s increasingly labelled by gold particles. It shows that indeed you can make cells that talk to each other and they can change the composition of the material over time. Ultimately, we hope to emulate how natural systems, like bone, form. No one tells bone what to do, but it generates a material in response to environmental signals”.

I like the bone analogy. Some months ago I visited another lab here in Cambridge where they use natural animal traits to design applications for science. You can read about my visit to the Karp Laboratory for Advanced Biomaterials and Stem Cell Based Therapeutics here, but the general idea is that researchers mimic the natural world. Lab Director Dr Jeffrey Karp explained that evolution offered incredible examples of innovation that could be used for scientific research today. We were shown examples of how porcupine needles are used to model surgical needles, and how gecko climbing techniques can be applied to medical adhesive design.

I look forward to learning about possible applications.

A Miracle Material?

Plastic and its use on mass causes many problems as we all know. It is not biodegradable, made from oil, difficult to recycle and can be found almost everywhere floating in the sea or buried on land. What we need is something to replace it.

Over the last year researchers at the MMC in Paris have been working on a new material. What they have developed is something that might change the future of manufacturing.

See this short article for a more complete description.

Their material is called a vitrimer, it is organic, strong, lightweight and looks to bridge the gap between thermoplastics and thermoset products.

Will vitrimer replace plastic?

Could this be the future of manufacturing?

What this actually means to you and me is a material that is solid but workable across a wide temperature range, so doesn’t melt like plastic, break like glass, can be shaped after production (unlike plastic or other polymers) and easily recycled.

The material can be sculptured without the need for extreme heat, so can be liquefied and moulded and then bent once finished. This makes it an incredibly versatile substance for use in electronics, car manufacturing and many different fields of engineering.

Advantages include the possibility of not using moulds for large structures that produce shapes that cannot be adjusted. If necessary the form required can be made in-situ and manipulated to fit, something that is not possible with steel for example.

The constitution of the materials determines its rigidity, so you can make it like thick rubber with flexibility at room temperature or much more rigid, but it is not brittle and so will not snap.

Given the many problems associated with plastics and the weight issues of using steel, this material looks to offer the promise of a more versatile, easily recyclable, reusable and less polluting alternative, and certain sectors of the scientific community are calling it a wonder material.

One to watch I would say.