Use of nanoparticles for controlled release of biocides in solid wood

Abstract

The fungicides tebuconazole and chlorothalonil were successfully incorporated into polymeric nanoparticles with median particle diameters of 100–250 nm. Polyvinylpyridine (PVPy) and polyvinylpyridine‐co‐styrene (10% styrene and 30% styrene) were employed as the polymer matrix. The size of the nanoparticle increased with increased styrene content. The biocide also affected particle size, with chlorothalonil consistently yielding larger nanoparticles than tebuconazole. The release of the biocides from the polymeric nanoparticles was studied by suspending them in water. The release rate of both tebuconazole and chlorothalonil decreased with increased styrene content in the matrix, and chlorothalonil consistently released more slowly from the polymeric nanoparticles than did tebuconazole. It was found that biocides were successfully introduced into solid wood by incorporating them within polymeric nanoparticles, suspending the nanoparticles in water, and using the suspension to treat the wood with conventional pressure treatments. Once in the wood, the polymer matrix serves as a reservoir for the biocide and controls its release rate into the wood. Southern pine sapwood samples were treated with biocide‐containing nanoparticles suspended in water, then exposed to the wood decay fungus Gloeophyllum trabeum using a simple wafer test. Samples exhibited fungal resistance at appropriate levels of biocide incorporation. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 458–465, 2001

Nanotechnology for Plant Disease Management

“…Starting in 1997, initial studies on nanofungicides were conducted on incorporating fungicides into solid wood [36,[72][73][74]. Since then, conventional fungicides (20 studies) and biocides with antifungal properties (6 studies) have been conducted with a wide range of nanoparticles ( Table 2).…”

“…In a series of studies, tebuconazole and chlorothalonil were loaded into a wide range of nanoparticles to improve the low solubility of the fungicides for deployment into solid woods [36,[72][73][74]. All four studies tested the mass lost due to decay from Gloeophyllum trabeum in southern yellow pine wood over 50-55 days (later trials also included birch, Trametes versicolor, KATHON 930, and the insecticide chlorpyrifos).…”

La nanotecnología y los retos de sostenibilidad del sistema agroalimentario

“…En otro trabajo de estos mismos investigadores, se encapsuló un fungicida, la validamicina, en este mismo tipo de nanopartículas, con buenos resultados en términos de tiempo de liberación. También, se han usado nanopartículas poliméricas para encapsular pesticidas sintéti-cos, lo cual incrementa su actividad biológica contra plagas específicas (33). Esta tecnología ha sido usada para mejorar la factibilidad del uso de aceites esenciales como biocidas naturales (34).…”

“…Un principio similar al descrito anteriormente puede usarse para mejorar la acción de los fertiliizantes, en este caso, para reducir las pérdidas de nitrógeno (37). El nitrógeno encapsulado en nanopartículas puede aprovecharse mejor, ya que los tejidos absorbentes de las plantas son nanopororosos, lo cual haría a los fertilizantes más eficientes y económicos a largo plazo (33). Las zeolitas, que son silicatos de aluminio nanoporosos que se encuentran naturalmente o son sintetizados, posibilitan el intercambio iónico y la deshidratación reversible.…”

Innovative Wood Surface Treatments Based on Nanotechnology

“…In the case of polymeric nanocarriers, an encapsulation of the active ingredient into polymeric nanocarriers can be conducted by several techniques, such as nanoprecipitation [19]. Several types of polymeric nanocarriers that may be used for active ingredient delivery are depicted in Figure 1 [9,11,[19][20][21][22]. The incorporation of organic biocides into polymeric nanoparticles and the subsequent introduction of the nanoparticles into wood may be advantageous.…”