Tag Archives: bacteria

New Approach to Wound Healing Easy on Skin, Tough on Bacteria

Washington, D.C. — In a presentation  to the American Chemical Society meeting, Ankit Agarwal, a postdoctoral researcher at the University of Wisconsin-Madison, described an experimental approach to wound healing that could take advantage of silver’s anti-bacterial properties, while sidestepping the damage silver can cause to cells needed for healing.

Silver is widely used to prevent bacterial contamination in wound dressings, says Agarwal, “but these dressings deliver a very large load of silver, and that can kill a lot of cells in the wound.”
Wound healing is a particular problem in diabetes, where poor blood supply that inhibits healing can require amputations, and also in burn wards. Agarwal says some burn surgeons avoid silver dressings despite their constant concern with infection.
Using a new approach, Agarwal has crafted an ultra-thin material carrying a precise dose of silver. One square inch contains just 0.4 percent of the silver that is found in the silver-treated antibacterial bandages now used in medicine.
In tests in lab dishes, the low concentration of silver killed 99.9999 percent of the bacteria but did not damage cells called fibroblasts that are needed to repair a wound.
Agarwal builds the experimental material from polyelectrolyte multilayers — a sandwich of ultra-thin polymers that adhere through electrical attraction. To make the sandwich, Agarwal alternately dips a glass plate in two solutions of oppositely charged polymers and finally adds a precise dose of silver.
“This architecture is very easily tuned to different applications,” Agarwal says, because it allows exact control of such factors as thickness, porosity and silver content. The final sandwich may range from a few nanometers to several hundred nanometers in thickness. (One nanometer is one-billionth of a meter; a human hair is about 60,000 nanometers in diameter.)
Nicholas Abbott, a professor of chemical and biological engineering who advises Agarwal, says during the past decade, “about a bazillion papers have been published on polyelectrolyte multilayers. It’s been a tremendous investment by material scientists, and that investment is now ripe to be exploited.”
Read more at HealAlerts

Peptide-containing nanofibers keep bacterial infections at bay

Researchers have developed a new infection-blocking material made of peptide-containing nanofibers that works against antibiotic-resistant bacteria and could one day be incorporated into wound dressings (ACS Infect. Dis. 2017, DOI: 10.1021/acsinfec​dis.6b00173).

The approach targets bacterial quorum sensing—a mode of chemical communication used by bacteria to detect other bacteria. When they sense that enough of their kind are present, they can mount an infectious attack.

Read more at Chemical and Engineering News

One Doctor Exploring Wound Care on Earth and in Space

In laboratories all across the globe, scientists are uncovering new and exciting breakthroughs in the realm of wound healing.

For instance, a team out of Texas is blinding bacteria to prevent their spread. Meanwhile, a collective of doctors from the U.K. recently developed some intriguing new vacuum tech to treat chronic ulcers. There’s even been research into drug treatments, like how opioids may actually prevent proper wound care.

Each team has taken a different approach or tackled a unique situation or medical ailment, and that ensures a more well-rounded coverage that helps a larger pool of patients. However, few scientists have a more grand scope than Ronke Olabisi, a professor of biomedical engineering at Rutgers University.

Reaching for the stars

As the university explained in a recent press release, Olabisi is hard at work on several projects aimed at improving wound healing both on earth and during manned space missions. During space travel, especially as astronauts spend months at a time in stations, the lack of gravity has a huge impact on the human body. Muscle and bones will actually start to deteriorate, and tissues will lose much of their elasticity. Olabisi’s main goal is to study in-depth why this occurs and how to fix, and she believes she can apply much of the same knowledge to wound care on Earth.

Read more at Advanced Tissue