A facile one-pot route to fabricate clothianidin-loaded ZIF-8 nanoparticles with biocompatibility and long-term efficacy.

Abstract

Neonicotinoids are among the most essential chemical insecticides worldwide because of their high activity against many important pests and wide application. However, their application is limited by their toxicity to honeybees. Therefore, the development of a facile route to fabricate efficient and eco-friendly pesticide formulations is of great significance. In this study, clothianidin-loaded zeolitic imidazolate framework-8 (CLO@ZIF-8) nanoparticles were fabricated by a facile one-pot route using zinc nitrate as a Zn2+ source and characterised by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, energy-dispersive spectrometry, and Fourier transform infrared spectroscopy. Based on the pH response of ZIF-8, a "burst release effect" was observed for CLO@ZIF-8 at pH values of 3 and 5 within 12 h, in contrast to the slow and sustainable release at pH 8. CLO@ZIF-8 improved the retention ability of the pesticide liquid and remained 70% control efficacy on Nilaparvata lugens after water rinsed. The pH response of CLO@ZIF-8 allowed it to maintain 43% control efficacy against Nilaparvata lugen after 10 days of application, which was twice as clothianidin solution (SCA). Moreover, CLO@ZIF-8 reduced the acute toxicity to honeybees (Apis mellifera) by at least 120 times compared with SCA. This study provides new insights into the application of ZIF-8 to neonicotinoids and suggests the need for the development of a biocompatible and eco-friendly pesticide formulation. This article is protected by copyright. All rights reserved.