Highly Stable, Excellent Foliar Adhesion and Anti-Photodegradation Nucleic Acid-Peptide Coacervates for Broad Agrochemicals Delivery.

Agrochemicals play a pivotal role in the management of pests and diseases and the way agrochemicals are utilized exerts significant impacts on the environment. Ensuring rational application and improving utilization rates of agrochemicals are major demands in developing green delivery systems. Herein, a model of nucleic acid-peptide coacervate (NPC) for agrochemical delivery is presented, which is formed by mixing negatively charged single-stranded DNAs with positively charged poly-L-lysine. The NPC microsystem exhibits broad loading capacities for various types of agrochemicals. Furthermore, the NPCs demonstrate remarkable protection against photodegradation for photosensitive agrochemicals. In the foliar interactions, the NPCs exhibit excellent wetting performances and foliar adhesion on hydrophobic cabbage leaves and wheat leaves infected with powdery mildew to facilitate direct spaying in practical applications. Subsequently, the NPC microsystem is stabilized against coalescence by a charged comb polymer. Then, the NPC loaded with emamectin benzoates (EBs) exhibited significantly higher insecticidal activity compared to free EBs. This enhanced efficacy can be attributed to the higher insect uptake efficiency of the NPC formulation, as evidenced by fluorescent imaging of mosquito larvae. This coacervate model provides a new biocompatible and highly efficient system for future agrochemical delivery that actively contributes to eco-friendly and sustainable agriculture.