Carvacrol encapsulation in MIL-100(Fe) nanoparticles. To encapsulate the natural preserving food molecule, carvacrol, we followed a simple green method consisting of the direct impregnation of previously obtained MIL-100(Fe) nanoparticles with a concentrated carvacrol solution (Figure ). Different experimental parameters including solvents and reaction times were investigated (Table ). It was found that carvacrol encapsulation was favoured under certain aqueous-alcoholic mixtures in which carvacrol is poorly soluble and forms a milky emulsion, this parameter resulting key for a successful encapsulation.