Novel photodegradable insecticide W/TiO(2)/Avermectin nanocomposites obtained by polyelectrolytes assembly.
Colloids Surf B Biointerfaces
; 83(1): 148-54, 2011 Mar.
Article
em En
| MEDLINE
| ID: mdl-21131183
ABSTRACT
Stable and even microcrystals of Avermectin (AVM) were produced by recrystallization in presence of a stabilizer. Sequential layer growth was achieved by the layer-by-layer (LbL) self-assembly of biocompatible polyelectrolytes (PEs). The coated colloids were characterized using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The in vitro release of Avermectin from microcapsules was studied under the simulated insect midgut conditions. W-doped TiO(2) photocatalysts were synthesized by a simple hydrothermal method, and characterized by Brunauer-Emmett-Teller (BET) surface area measurements and SEM. The photocatalytic activities of photocatalysts, which were undoped with TiO(2) and W-doped TiO(2), were evaluated by the photocatalytic oxidation degradation of AVM microcapsules in aqueous solution under UV illumination. The toxicity of the photodegradable insecticide was evaluated by the adult stage Martianus dermestoides. The results showed that AVM microcrystals which were obtained by association had a mean length of 13.8µm and a zeta potential of -34.7mV. The drug loading and encapsulation efficiency were 65.57±0.96% and 46.15±0.96%, respectively. The in vitro release experiments revealed that the polyelectrolytes prolonged the release time of the encapsulated AVM microcrystals. The sample which was prepared at 120°C with 4.0mol% W-doped amount had the highest photocatalytic activity. Toxicity of the novel photodegradable insecticide was higher in the adult stage compared to the 95% AVM as indicated by the lower LC(50) value.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fotólise
/
Titânio
/
Tungstênio
/
Ivermectina
/
Eletrólitos
/
Nanocompostos
/
Inseticidas
Limite:
Animals
Idioma:
En
Revista:
Colloids Surf B Biointerfaces
Ano de publicação:
2011
Tipo de documento:
Article