Biomaterial To Replace Plastics And Reduce Pollution

An inexpensive biomaterial that can be used to sustainably replace plastic barrier coatings in packaging and many other applications has been developed by Penn State researchers, who predict its adoption would greatly reduce pollution. Completely compostable, the material — a polysaccharide polyelectrolyte complex — is comprised of nearly equal parts of treated cellulose pulp from wood or cotton, and chitosan, which is derived from chitin — the primary ingredient in the exoskeletons of arthropods and crustaceans. The main source of chitin is the mountains of leftover shells from lobsters, crabs and shrimp consumed by humans.

These environmentally friendly barrier coatings have numerous applications ranging from water-resistant paper, to coatings for ceiling tiles and wallboard, to food coatings to seal in freshness, according to lead researcher Jeffrey Catchmark, professor of agricultural and biological engineering, College of Agricultural Sciences.

In the research, paperboard coated with the biomaterial exhibited strong oil and water barrier properties. The coating also resisted toluene, heptane and salt solutions and exhibited improved wet and dry mechanical and water vapor barrier properties.

The material’s unexpected strong, insoluble adhesive properties are useful for packaging as well as other applications, such as better performing, fully natural wood-fiber composites for construction and even flooring,” Jeffrey Catchmark said. “And the technology has the potential to be incorporated into foods to reduce fat uptake during frying and maintain crispness. Since the coating is essentially fiber-based, it is a means of adding fiber to diets.”

Source: http://news.psu.edu/

Stem Cells Boost Bones Repair

A recent study, affiliated with UNIST (South Korea) has developed a new method of repairing injured bone using stem cells from human bone marrow and a carbon material with photocatalytic properties, which could lead to powerful treatments for skeletal system injuries, such as fractures or periodontal disease. In the study, the research team reported that the use of human bone marrow-derived mesenchymal stem cells (hBMSCs) has been tried successfully in fracture treatment due to their potential to regenerate bone in patients who have lost large areas of bone from either disease or trauma. Recently, many attempts have been made to enhance the function of stem cells using carbon nanotubes, graphenes, and nano-oxides.

Professor Kim and Professor Suh (UNIST) examined the C₃N₄sheets. They discovered that this material absorbs red light and then emits fluorescence, which can be used to speed up bone regeneration. Professor Suh conducted a biomedical application of this material. After two days of testing, the material showed no cytotoxicity, making it useful as biomaterials.

bone-repairUpper left) Chemical bonding and physical structure of C₃N₄4 sheets. (Lower left) In a liquid state, red light is transmitted at a maximum of 450nm and emitted at a wavelength of 635 nm. (Right) After 4 weeks of loading C₃N₄4 sheets into the skull-damaged mice, the skull was regenerated by more than 90%.

This research has opened up the possibility of developing a new medicine that effectively treats skeletal injuries, such as fractures and osteoporosis,” said Professor Young-Kyo Seo. “It will be a very useful tool for making artificial joints and teeth with the use of 3D printing. This is an important milestone in the analysis of biomechanical functions needed for the development of biomaterials, including adjuvants for hard tissues such as damaged bones and teeth.”

This research has been jointly conducted by Professor Youngkyo Seo of Life Sciences and Dr. Jitendra N. Tiwari of Chemistry in collaboration with Professor Kwang S. Kim of Natural Science, Professor Pann-Ghill Suh of Life Sciences, and seven other researchers from UNIST.  The results of the study has been published in the January issue of ACS Nano journal.

Source: https://news.unist.ac.kr/

Nano-Reactor Produces Hydrogen

Scientists at Indiana University (IU) have created a highly efficient biomaterial that catalyzes the formation of hydrogen — one half of the “holy grail” of splitting H2O to make hydrogen and oxygen for fueling cheap and efficient cars that run on water. A modified enzyme that gains strength from being protected within the protein shell — or “caps id” — of a bacterial virus, this new material is 150 times more efficient than the unaltered form of the enzyme.

indianaP22-Hyd, a new biomaterial created by encapsulating a hydrogen-producing enzyme within a virus shell.

Essentially, we’ve taken a virus’s ability to self-assemble myriad genetic building blocks and incorporated a very fragile and sensitive enzyme with the remarkable property of taking in protons and spitting out hydrogen gas,” said Trevor Douglas, Professor of Chemistry in the IU Bloomington College of Arts and Sciences’ Department of Chemistry, who led the study “The end result is a virus-like particle that behaves the same as a highly sophisticated material that catalyzes the production of hydrogen.”

The process of creating tahe material was recently reported in “Self-assembling biomolecular catalysts for hydrogen production” in the journal Nature Chemistry.

Source: http://news.indiana.edu/

Injectable 3D Vaccine Fights Cancer and HIV

One of the reasons cancer is so deadly is that it can evade attack from the body’s immune system, which allows tumors to flourish and spread. Scientists can try to induce the immune system, known as immunotherapy, to go into attack mode to fight cancer and to build long lasting immune resistance to cancer cells. Now, researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard’s School of Engineering and Applied Sciences (SEAS) show a non–surgical injection of programmable biomaterial that spontaneously assembles in vivo into a 3D structure could fight and even help prevent cancer and also infectious disease such as HIV. Their findings are reported in Nature Biotechnology.

dentritic cells
A microscope image shows many of the immune system’s dendritic cells that were collected from a 3D scaffold three days after in vivo injection. The 3D scaffold effectively recruits and activates the dendritic cells to trigger an immune response against specific cells, such as cancerous cells

We can create 3D structures using minimally–invasive delivery to enrich and activate a host’s immune cells to target and attack harmful cells in vivo,” said the study’s senior author David Mooney, Ph.D., who is a Wyss Institute Core Faculty member and the Robert P. Pinkas Professor of Bioengineering at Harvard SEAS. “Nano–sized mesoporous silica particles have already been established as useful for manipulating individual cells from the inside, but this is the first time that larger particles, in the micron–sized range, are used to create a 3D in vivo scaffold that can recruit and attract tens of millions of immune cells,” said co-lead author Jaeyun Kim, Ph.D., an Assistant Professor of Chemical Engineering at Sungkyunkwan University (Korea) and a former Wyss Institute Postdoctoral Fellow.
Source: http://wyss.harvard.edu/