How Magnetic Soap Works

Ever wondered how soap gets things clean and how it can prevent us from getting sick? Discovery News' Kasey-Dee Gardner scrubs in to find the answer.

It might sound like a novelty out of the pages of Archie McPhee -- or the worst supervillain plot ever to sully the pages of Bond or Batman -- but magnetic soap is attracting a lot of attention.

On Jan. 20, 2012, a University of Bristol team led by Julian Eastoe published a paper online announcing a simple idea with far-reaching implications: soaps that can be moved or removed using magnetism. To see why this idea has such pull, imagine cleaning up an environmental disaster like the Deepwater Horizon oil spill, then sweeping up the leftovers with magnetic booms to ensure that no oil-dispersing substances, or dispersants, remain behind.

Because cleansers can linger or spread, inflicting their own brand of harm, mopping up industrial spills has long meant picking your poison. Oil cleanup crews use dispersants to save otters and seabirds from immediate hazards but risk damaging sea life, particularly fish eggs, in the process [source: Sohn].

From an environmental standpoint, that won't wash, so researchers have worked themselves into a lather trying to pump out soaps and dispersants that can be easily removed from the ecosystem, or that will break down on their own if left behind [source: Boyle]. Over the years, they have spun out soaps that react to pH, electrolyte concentration, temperature, carbon dioxide and light [sources: Brown; Flatow]. Altering the temperature of water requires beaucoup energy, however, and changing a substance's internal chemistry remains quite difficult -- to say nothing of the potential environmental consequences of doing either [source: Eastoe].

Now, magnetic soap has joined the load of novel cleaners. Although still in the early stages of experimentation and development, it could one day bring a breath of springtime-fresh air to notoriously sticky cleaning jobs [source: Flatow]. Currently, we rely on the normal detergent action of soaps like Dawn, which might "take grease out of your way" but can only do so much for oil-soaked otters [source: Drury]. Magnetic soaps can grab ahold of oil and then overcome both gravity and surface tension to stick to magnets.

The technique applies not only to soaps, but also to a broad and ubiquitous class of substances called surfactants, or "surface active agents," that convince typically standoffish solids and liquids, such as oil and water or water and dirt, to mix. Equally important, they hold onto removed dirt, preventing it from clumping up and redispersing on washables. Surfactants play essential roles in tanning and dying, perfumes and beauty products, and cooking and baking.

As in any good social event, successful mixing comes from lowering tensions through good chemistry.