Development of biodegradable starch-based lambda-cyhalothrin microcapsules for sustainable long-term pest control and enhanced utilization efficacy

The inefficiency of traditional pesticides leads to significant resource waste, severe environmental pollution, and potential threats to human health. Pesticide microcapsules present a promising strategy for developing environmentally friendly, safe, and sustained-release formulations. In this study, we produced degradable starch nanocrystals (SNCs) via acid hydrolysis and employed octenyl succinic anhydride-modified SNCs (O-SNCs) to fabricate pesticide microcapsules. Specifically, O-SNCs were used to emulsify molten lambda-cyhalothrin (LC), forming a Pickering emulsion. Subsequent interfacial polymerization of this emulsion yielded microcapsules, whose size can be adjusted by varying the O-SNCs content. These microcapsules exhibit high encapsulation efficiency and excellent storage stability. Furthermore, they demonstrate superior sustained pest control efficacy while significantly reducing acute toxicity to zebrafish and earthworms. This study provides valuable insights for designing sustainable, environmentally friendly, and highly effective pesticide formulations.