Italy's world-renowned restorers will soon have another tool in their extensive armoury: a balm that can salvage even the most sensitive artworks.
A team of researchers at Florence University have developed a kind of microemulsion, which has so far helped restore two frescoes, one of which previously believed beyond repair.
The microemulsion was successfully applied in gel format to a painting on the walls of Siena's Santa Maria della Scala Church and to a fresco in the San Nicola al Ceppo Oratory in Florence.
The latter was thought to have been irrevocably damaged in 1966, a victim of the Florentine flood that killed 30 people and submerged the city in up to 22 feet of water.
"This second project was extremely difficult to deal with," said Piero Baglioni, a Physical Chemistry Professor at Florence University and the study's coordinator.
"This is because the fresco was covered with tar deposits, which had crystallized after 40 years.
"We added ammonium carbonate to the microemulsion; this puffed up the tar, which was then trapped and removed by the gel".
The treatment is a microemulsion, containing water and oil, as well as a substance that allows the two to mix. Suspended in the water are millions of miniscule molecules called alkylpolyglycosides (APGs).
"The reason APGs work is because they are thousands of times smaller than normal [oil in water] suspensions, meaning they are much more effective," explained Baglioni.
"APGs are also much less toxic for the restorers than normal solvents, as well as being more delicate on the underlying picture. The ones we used were designed and produced by an Italian firm".
The balm has so far only been tested on frescoes but Baglioni's team, whose research has been published in the American Chemical Society's Langmuir magazine, believes it could have a much wider application.
IMPROVED BALM BEING STUDIED, CAN BE USED ON OIL PAINTINGS.
"We already have tests that show us it can be used on oil paintings," said one of the study's authors, Rodorico Giorgi.
"We are now studying other, even better types of balms that use the same technology".
The balm is expected to be a valuable asset to Italian restorers, who are among the most skilled in the world.
Although best known for their astonishing work on masterpieces such as Leonardo da Vinci's Last Supper or the Sistine Chapel, the talents of Italian restorers encompass a much broader field.
In recent years their expertise has helped salvage treasures from Afghanistan and Iraq, and they have also been involved in training projects worldwide, teaching local experts the latest restoration and rescue techniques.
In addition, the UN's cultural organization, UNESCO, has granted them a special role, representing the body in projects aimed at safeguarding artistic, historic and archaeological monuments around the globe.
