Construction of pH-responsive nucleic acid delivery system based on amination of BSA and schiff-base for precise pest control

Pest RNAi control is essential for sustainable agriculture, and critical single-copy genes like heat shock protein 90 (Hsp90) in lepidopterans are ideal targets for new pest control strategies. However, current application technologies struggle to ensure RNAi efficiency, affecting control effectiveness. Herein, we illustrate a nucleic acid delivery system using bovine serum albumin cross-linked with diamine (cBSA) to deliver dsRNA targeting Hsp90 in Spodoptera litura, a major agricultural pest causing significant crop losses. The prepared nucleic acid delivery system (GBSA·NPs) with acid-sensitive bond that easily releases dsRNA inside cells, which cell-based experiments showed an RNAi efficiency increase by 43.59 %. And experiments on individual insects showed that GBSA·NPs delivery nearly tripled RNAi efficiency compared to direct dsRNA treatment. Crucially, safety tests indicated that both the carrier and dsRNA are safe for natural enemies, facilitating precise pest control.