Italian researchers have solved an age-old problem of painting conservation with new technology: magnets. Restorers use special gels to work on small areas of a canvas, but removing them has remained a delicate operation that can damage the artwork. Now, Nature reports, chemists at the University of Florence have developed a magnetic gel that can be removed harmlessly.
The gel is a polymer, firm enough to be cut with scissors, that has nanoparticles of iron mixed into it. When applied to a canvas, it sucks up dirt with a cleaning agent that is then reabsorbed into the gel. The magnet then removes the gel. A conservator at London's Courtauld Institute calls the innovation "useful for very delicate surfaces." (More conservation stories.)