Size effects of lufenuron-loaded ZIF-8 nanoparticles on target deposition and insecticidal activity

Nanotechnology presents a significant opportunity to transform traditional chemical pesticides into more-efficient, environmentally friendly, and intelligent alternatives. It has emerged as a prominent research focus in contemporary agriculture. The particle size of pesticide-loaded nanoparticles (NPs) is a critical factor influencing the absorption efficiency of plants, because it affects the bioavailability of the active ingredient. Consequently, a thorough investigation into this key scientific issue of the size effects of nanopesticides on target deposition and biological activity is essential for improving the utilization efficiency of pesticides.

In this study, lufenuron-loaded zeolitic imidazolate framework-8 (Luf@ZIF-8) with four different particle sizes (386, 201, 103, and 64 nm) were facilely prepared. All NPs exhibited approximately spherical morphology. Luf@ZIF-8 with smaller sizes demonstrated excellent wetting properties and were more likely to adhere to plant surfaces. The 48-h cumulative release rate results indicated that the release rate of Luf@Z-64 (65.61%) was significantly higher than that of Luf@Z-386 (49.62%). At a treatment concentration of 5 mg/L, the 24-h mortality rate of Plutella xylostella in the Luf@Z-64 treatment group was 1.4 times higher than that in the Luf@Z-386 treatment group.

The wettability and biological activity of Luf@ZIF-8 increase as particle size decreases. Exploration of size effects offers valuable theoretical guidance for the development and preparation of nanopesticides with an optimal particle size. © 2025 Society of Chemical Industry.