A study on the pesticides-loading capacity of dendritic fibrous nano silica synthesized from 1-pentanol-water microemulsion with a low oil-water ratio

Abstract

Dendritic fibrous nano silica (DFNS) represents an optimal carrier material for pesticide constituents, due to its radial accessibility channels and high specific surface area. A low-energy methodology for synthesizing DFNS at a low volume ratio of oil to water is provided by employing 1-pentanol as the oil solvent in the microemulsion synthesis system, renowned for its remarkable stability and exceptional solubility. The DFNS@KM nano-pesticide was fabricated using a diffusion supported loading (DiSupLo) method and kresoxim-methyl (KM) as the template drug. Findings from FT-IR, XRD, TG, DTA, and BET analyses revealed the physical adsorption of KM onto the synthesized DFNS without any chemical bonding, with KM mainly existing in an amorphous state within the channels. High-performance liquid chromatography (HPLC) measurements demonstrated that the loading amount and encapsulation efficiency of DFNS@KM were primarily dependent on the KM to DFNS ratio, with minimal effects observed from loading temperature and time. The loading amount and encapsulation efficiency of DFNS@KM were found to be 63.09% and 84.12%, respectively. Furthermore, DFNS effectively prolonged the release of KM, with a cumulative release rate of 85.43% over 180 hours. The successful loading of pesticide components into DFNS synthesized with a low oil-to-water ratio provides theoretical support for the industrialization of nano-pesticides, with significant implications for enhancing pesticide utilization, reducing pesticide dosage, augmenting agricultural efficiency, and promoting sustainable agricultural development.