Alessandra Scano (Chemical and Geological Science Dept., University of Cagliari, Cittadella Universitaria di Monserrato, SS554 Bivio per Sestu, 09042 Monserrato (Cagliari)), Martina Pilloni (Chemical and Geological Science Dept., University of Cagliari, Cittadella Universitaria di Monserrato, SS554 Bivio per Sestu, 09042 Monserrato (Cagliari)), Valentina Cabras (Chemical and Geological Science Dept., University of Cagliari, Cittadella Universitaria di Monserrato, SS554 Bivio per Sestu, 09042 Monserrato (Cagliari)), Federico Ebau (Chemical and Geological Science Dept., University of Cagliari, Cittadella Universitaria di Monserrato, SS554 Bivio per Sestu, 09042 Monserrato (Cagliari)), Maria Letizia Manca (Life and Environment Science Dept., Section of Drug Sciences, CNBS, University of Cagliari, Via Ospedale 72, 09124 Cagliari), Anna Maria Fadda (Life and Environment Science Dept., Section of Drug Sciences, CNBS, University of Cagliari, Via Ospedale 72, 09124 Cagliari), Guido Ennas (Chemical and Geological Science Dept., University of Cagliari, Cittadella Universitaria di Monserrato, SS554 Bivio per Sestu, 09042 Monserrato (Cagliari))