Silver nanoparticles are very effective at killing bacteria, finding use in everything from water filters to non-smelly clothing. That said, there are some major concerns regarding the effects that those particles may have on human health and on the environment. Among other things, it has been suggested that they cause cell death, and compromise the immune system. Now, however, scientists at Sweden's KTH Royal Institute of Technology have come up with what could be a less harmful alternative – red algae.

More specifically, the KTH team is looking at lanosol, which is an antibacterial compound found in red Rhodophyta seaweed.

Led by Prof. Mikael Hedenqvist, the researchers have used electrospinning techniques to create very fine threads made from a blend of lanosol and bio-compatible plastic. These can then be added to other materials, or woven together to form fabrics. Because the threads are so skinny – about one-hundredth the width of a human hair – the active surface area of these fabrics is maximized.

A close look at a swatch of lanosol-containing antibacterial fabric

Additionally, the lanosol mixes thoroughly with the plastic, ending up being very evenly dispersed throughout each thread. By contrast, silver nanoparticles have a tendency to form into clumps, negatively affecting antibacterial fabrics' mechanical properties.

It is now hoped that lanosol-based materials could find use in wound dressings or air filters in hospitals. Such applications would be particularly appropriate, as lanosol has been shown to kill 99.99 percent of Staphylococcus aureus bacteria, which is the leading cause of skin and wound infections in hospital settings.

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