Nano-based smart pesticide formulations utilizing starch nanocrystals: Achieving high stability and extended effective duration

Intense long-term application of pesticides on farmlands causes dramatic environmental and health issues. However, these problems can be effectively reduced by the development of sustained release nano-formulations utilizing the application of nanotechnology in pesticide delivery. SNCs (Starch nanocrystals) have recently emerged as promising nanocarriers due to their stability, biodegradability, and ease of preparation. SNCs with a stable structure and uniform porosity were successfully obtained after removing the amorphous area of corn starch using sulfuric acid and ultrasonic treatment. TMX (Thiamethoxam) nanoparticles were achieved through electrostatic interactions with these nanocrystals. Compared to TMX technical material, the SNC carrier loaded with TMX exhibited significantly higher insecticidal activity against Diaphorina citri, a notorious pest in citrus production. In contrast, the nano preparation displayed a similar LC50 against D. citri compared to TMX suspension. Moreover, toxicity tests on bees demonstrated significantly reduced toxicity in the nano preparation versus TMX. SNCs prepared via sulfuric acid hydrolysis and ultrasound can be effective carriers for TMX, thus enhancing its utilization rate while reducing toxicity to bees. This approach offers a valuable tool for developing environmentally friendly nano-pesticide carriers and controlling pests like D. citri.