Glycine-doped metal–organic frameworks as intelligent nanocarriers to enhance pesticide delivery and provide micronutrient in plants

The development of multifunctional pesticide-delivery system is of practical significance for realizing efficient utilization of pesticides and minimizing environmental risks. In this work, methoxyfenozide (Met)-loaded glycine-doped zeolitic imidazolate framework-8 composites (Met@Gly@ZIF-8) for intelligent-release of Met and effective pest management were facilely constructed. The physical properties of Met@Gly@ZIF-8, including ultraviolet (UV) resistance, deposition and release profiles were evaluated. Compared with Met, the residual content after UV irradiation and retention content on cabbage leaves of Met@Gly@ZIF-8 increased by 121.2% and 98.2%, respectively, and the contact angle on foliar decreased by 26.5% compared with Met suspension concentrate (SC), which demonstrating better photolysis resistance, deposition and wetting ability. Release experiments indicated that Met@Gly@ZIF-8 possessed significant stimuli-responsive release characteristics which were negatively correlated with pH, due to the acidic degradation of ZIF-8. The biological activity experiments showed that Met@Gly@ZIF-8 possessed elevated control efficacy on Plutella xylostella compared with Met and reduced the LC50 value by 53.2%. The application performance experiments indicated that the penetration amount of Met@Gly@ZIF-8 in cabbage leaves increased by 194.7% and the translocation factor (TFleaf) increased by 63.3%, respectively, as compared with those of Met. Compared with the blank control, Gly@ZIF-8 and Met@Gly@ZIF-8 increased the total biomass by 37.8% and 25.7%, respectively, exhibiting nutritional functions for plants. Toxicity test showed that Met@Gly@ZIF-8 was relatively safe for zebrafish compared with Met. The present approach could be strategically promising for constructing functional and environmentally friendly smart-nanopesticide.