Natural rosin modified carboxymethyl cellulose delivery system with lowered toxicity for long-term pest control.

The increasing world-wide demand for food has prompted the development of efficient and environmentally friendly pesticide formulations. In this article, we have prepared CMC-g-PRSG carrier based on two compounds from natural materials carboxymethyl cellulose (CMC) and rosin (RS). The model pesticide avermectin (AVM) was encapsulated through hydrophobic interaction, and self-assembled to form nanopesticide AVM@CMC-g-PRSG with an average particle size of 167 nm. The prepared nanopesticide displays enhanced dispersibility and stability of AVM in water, and can effectively adhere to the leaves to prevent loss. The release rate of AVM encapsulated in the nanocarrier can be controlled by adjusting pH, and AVM half-life under ultraviolet radiation shows a 3-fold increase allowing control of pests for prolonged periods of time in practical applications. Biological safety tests showed that AVM@CMC-g-PRSG effectively reduces the toxicity of AVM to aquatic animals. Therefore, the cheap and degradable carrier CMC-g-PRSG can improve the effect of hydrophobic pesticides.