They tested their treated materials with Staphylococcus aureus and Escherichia coli, the gram-positive and gram-negative bacteria that are always giving humans a bad day.

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There is particular concern about Gram-negative bacteria (like E.coli and K. pneumonia), due to their outer membrane which can prevent some antibiotics from penetrating the cell.

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The process took advantage of an electric charge differential existing between the polymer, which was positively charged, and the bacteria cells, which carried a net negative charge.

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This, among other things, helps it to distinguish bacteria from human membranes, which have a less negative charge.

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By using atmospheric air and negative ions, a natural cleansing agent, it fights dirt and bacteria with nature's own weapon, he said.

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