Effect of Silver Nanoparticles Synthesized with NPsAg-Ethylene Glycol (C₂H₆O₂) on Brown Decay and White Decay Fungi of Nine Tropical Woods

Nanotechnology applications have potential for improving decay resistance of wood under tropical conditions. In this work, nine commercial timbers from Costa Rica were treated with silver nanoparticles synthetized with NPsAg-ethylene glycol through pressure. White-rot (Trametes versicolor) and brown-rot (Lenzites acuta) fungi were tested. According to the results, the sizes of the synthetized silver nanoparticles were 40 to 100 nm. The retention achieved was of 16 to 112 mg of silver per kilogram of wood or 7.7 to 25.1 g of silver per cubic meter of wood. Specific gravity affected the retention in Cordia alliodora, Gmelina arborea, Goethalsia meiantha, Tectona grandis and Vochysia ferruginea. Loss of weight was less in wood treated with silver nanoparticles, its values ranging from 8% to 35% in L. acuta and 7% to 11% in T. versicolor. As for durability, the wood of the species treated with silver nanoparticles is classified as highly resistant to T. versicolor and moderately to moderately resistant to L. acuta. Moreover, the effect of retention of the nanoparticles was not significant for weight in all of the species. This parameter was positively affected in C. odorata, E. cyclocarpum, G. arborea, T. grandis and V. ferruginea, although unaffected for other species.