Sustainable nanocarriers fabricated by the dipeptide-based co-assemblies for enhancing the delivery and translocation of herbicide

Pesticide delivery platforms are effective means to improve the control efficiency of pesticide through multiple functionalities. However, the prevalent use of pesticide carriers is often hindered by complex synthetic pathways, environmentally unfriendly components, and limited loading capacities, which restrict their practical applications in agriculture. In this work, we developed sustainable pesticide nanocarriers using a straightforward supramolecular co-assembly approach, which employed the bio-based diphenylalanine (FF) as the assembling molecule and the herbicide fluroxypyr (FP) as the active ingredient. Driven by the synergistic effects of hydrogen bonding, electrostatic interactions, π-π stacking, hydrophobic interactions and van der Waals forces, FP and FF co-assembled into stable assemblies with high loading capacity. Notably, the co-assemblies with different compositions exhibited tunable microstructures, including the wormlike micelles, micelles-arranged coils, and vesicles. Additionally, these nanocarriers demonstrated sensitive responsive release properties based on the FP/FF ratio and the change of pH value, and nearly 97.78% of FP could be released by the 1:1 co-assemblies at pH of 5. Furthermore, the alteration in size and microscopic morphology after co-assembly made FP easier to be translocated in the target weed, which ultimately enhanced the herbicidal activity. Overall, this work proposes a promising approach for greening and simplifying pesticide carriers, offering novel insights and strategies for sustainable agricultural development.