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/

How To Kill Cancer Stem Cells To Avoid Recurrence

Nanoparticles packed with a clinically used chemotherapy drug and coated with an oligosaccharide derived from the carapace of crustaceans might effectively target and kill cancer stem-like cells, according to a recent study led by researchers at The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James).

Cancer stem-like cells have characteristics of stem cells and are present in very low numbers in tumors. They are highly resistant to chemotherapy and radiation and are believed to play an important role in tumor recurrence. This laboratory and animal study showed that nanoparticles coated with the oligosaccharide called chitosan and encapsulating the chemotherapy drug doxorubicin can target and kill cancer stem-like cells six times more effectively than free doxorubicin.

chitosancoat

Our findings indicate that this nanoparticle delivery system increases the cytotoxicity of doxorubicin with no evidence of systemic toxic side effects in our animal model,” says principal investigator Xiaoming (Shawn) He, PhD, associate professor of Biomedical Engineering and a member of the OSUCCC – James Translational Therapeutics Program.

We believe that chitosan-decorated nanoparticles could also encapsulate other types of chemotherapy and be used to treat many types of cancer”.

This study, reported in the journal ACS Nano, showed that chitosan binds with a receptor on cancer stem-like cells called CD44, enabling the nanoparticles to target the malignant stem-like cells in a tumor.

Source: http://cancer.osu.edu/

How To Fix Damaged Hearts

In the U.S., someone suffers a heart attack every 34 seconds — their heart is starved of oxygen and suffers irreparable damage. Engineering new heart tissue in the laboratory that could eventually be implanted into patients could help, and scientists are reporting a promising approach tested with rat cells.

Gordana Vunjak-Novakovic, Rui L. Reis, Ana Martins and colleagues point out that when damaged, adult heart tissue can’t heal itself very well. The only way to fix an injured heart is with a transplant. But within the past decade, interest in regenerating just the lost tissue has surged. The trick is to find materials that, among other things, are nontoxic, won’t get attacked by the body’s immune system and allow for muscle cells to pass the electrical signals necessary for the heart to beat. Previous research has found that chitosan, which is obtained from shrimp and other crustacean shells, nearly fits the bill. In lab tests, scientists have used it as a scaffold for growing heart cells. But it doesn’t transmit electrical signals well. Vunjak-Novakovic’s team decided to build on the chitosan development and coax it to function more like a real heart.
heart
To the chitosan, they added carbon nanofibers, which can conduct electricity, and grew neonatal rat heart cells on the resulting scaffold. After two weeks, cells had filled all the pores and showed far better metabolic and electrical activity than with a chitosan scaffold alone. The cells on the chitosan/carbon scaffold also expressed cardiac genes at higher levels.
The findings have been published in the ACS journal Biomacromolecules.
Source: http://www.eurekalert.org/

Nanoparticule To Cure Acne

Advances in nanotechnology have demonstrated potential application of nanoparticles (NPs) for effective and targeted drug delivery. A research team from Albert Einstein College of Medicine in New York and University of California Los Angeles School of Medicine have investigated the antimicrobial and immunological properties and the feasibility of using NPs to deliver antimicrobial agents to treat a cutaneous pathogen. For instance acne is one of the most common dermatologic diseases affecting between 40-50 million people each year. While best known as bothersome part of puberty, affecting approximately 75% of teenagers, acne can persist or even first start during adulthood, causing emotional and physical distress as well as permanent disfigurement.

NPs synthesized with chitosan and alginate demonstrated a direct antimicrobial activity in vitro against Propionibacterium acnes, the bacterium linked to the pathogenesis of acne. By electron microscopy (EM) imaging, chitosan–alginate NPs were found to induce the disruption of the P. acnes cell membrane, providing a mechanism for the bactericidal effect.
Source: http://www.nature.com/