Stronger than steel and impressively elastic, spider silk is already a natural marvel. Yet researchers have improved upon the natural material even further by adding antibiotics to the silk that could aid in wound healing and recovery.
After five years of research, scientists at The University of Nottingham have managed to develop a novel technique that uses "click-chemistry" to tailor spider silk to specific applications. By attaching certain molecules to either the silk proteins or the resultant fibers, they can add drugs or chemicals to the material.
The key to the new material involves incorporating an amino acid with an azide group, which is widely used in "click" reactions in chemistry. By creating E.coli bacteria that can produce this newly modified spider silk, the researchers then found that they could incorporate certain molecules into the silk by targeting this newly added amino acid.
They then attached molecules, such as the antibiotic levofloxacin, and "clicked" them into place. When they did so, the team found that its anti-bacterial activity slowly released over a period of five days from the silk. How rapidly the drug is released could in theory be controlled, which means that it could potentially lead to the production of wound dressings that both dispel the antibiotic over time and form a natural, degradable scaffold for the healing body.
“There is the possibility of using the silk in advanced dressings for the treatment of slow-healing wounds such as diabetic ulcers,” explains Professor Neil Thomas, co-author of the study published in the journal Advanced Materials, in a statement. “Using our technique infection could be prevented over weeks or months by the controlled release of antibiotics. At the same time tissue regeneration is accelerated by silk fibers functioning as a temporary scaffold before being biodegraded.”
The added molecules can be applied so that they adhere to the silk proteins before or after they form the silk fiber. The team can even add a whole range of molecules that give the silk multiple different properties.
The researchers now plan to delve further into the research and examine exactly how they can use the new spider silk material. They hope their research will encourage other labs to do the same.