Researchers grow crops on super thin film
Japanese researchers at Mebiol have figured out a way to grow small crops of Earthly flora on clean sheets of hydrogel (commonly found in diapers), called Imec, that measures just tens of microns thick. Roots grow along the membrane, absorbing water through it, but the material is able to block out bacteria and viruses that could harm the plants.
Hydrogel helps grow new scar-free skin over third degree burns
By Ben Coxworth
20:32 December 16, 2011
Postdoctoral fellow Guoming Sun (left) and Sharon Gerecht, an assistant professor of chemical and biomolecular engineering, helped develop the burn-healing hydrogel
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Third-degree burns typically require very complex treatment, and leave nasty scars once they’ve healed. Researchers at Johns Hopkins University, however, are reporting success at treating such burns on lab mice, using a new type of hydrogel that grows new skin (as opposed to scar tissue) over burn sites. The gel contains no drugs or biological components - it’s made mainly from water and dissolved dextran, which is a sugar-like polymer.
The team, led by principal investigator Sharon Gerecht, had originally planned on infusing the hydrogel with stem cells and growth factors. Due to processes they don’t fully understand, however, the gel in its basic form was able to grow new skin - complete with hair follicles, blood vessels and skin oil glands. The growth process takes 21 days.
The scientists believe that the physical structure of the hydrogel could be guiding the tissue growth, and that it could be attracting bone marrow stem cells circulating in the blood stream, then signaling them to form into skin cells and blood vessels. One thing they do know is that inflammatory cells are able to easily penetrate and degrade the gel, allowing blood vessels to form quickly, which in turn supports new tissue growth.
Gerecht believes that the hydrogel should be inexpensive and easy to manufacture on a commercial scale, and that it could also be used to treat wounds such as skin ulcers. More animals trials are planned before human testing is able to begin, but because the gel is likely to be classified as a device and not as a medication, it could be approved for use within just a few years.
A paper on the Johns Hopkins research was published this week in the journalProceedings of the National Academy of Sciences.
New injectable gels toughen up after entering the body (11/18/2012)
cyberneticsnews.comGels that can be injected into the body, carrying drugs or cells that regenerate damaged tissue, hold promise for treating many types of disease, including cancer. However, these injectable gels don’t always maintain their solid structure once inside the body. MIT chemical engineers have now designed an injectable gel that responds to the body’s high temperature by forming a reinforcing network that makes the gel much more durable, allowing it to function over a longer period of time. The research team, led by Bradley Olsen, an assistant professor of chemical engineering, described the new gels in a recent issue of the journal Advanced Functional Materials. Lead author of the paper is Matthew Glassman, a graduate student in Olsen’s lab. Jacqueline Chan, a former visiting student at MIT, is also an author. Olsen and his students worked with a family of gels known as shear thinning hydrogels, which have a unique ability to switch between solid-like and liquid-like states. When exposed to mechanical stress - such as being pushed through an injection needle - these gels flow like fluid. But once inside the body, the gels return to their normal solid-like state. However, a drawback of these materials is that after they are injected into the body, they are still vulnerable to mechanical stresses. If such stresses make them undergo the transition to a liquid-like state again, they can fall apart. “Shear thinning is inherently not durable,” Olsen says. “How do you undergo a transition from not durable, which is required to be injected, to very durable, which is required for a long, useful implant life?” The MIT team answered that question by creating a reinforcing network within their gels that is activated only when the gel is heated to body temperature (37 degrees Celsius).
