Fabrication of ROS-responsive nanoparticles by modifying the interior pore-wall of mesoporous silica for smart delivery of azoxystrobin

Abstract

The suboptimal efficiency in pesticide utilization may elevate residues, posing safety risks to human food and non-target organisms. To address this challenge, delivery systems, such as pathogen infection stimuli-responsive carriers, can be employed to augment the efficiency of fungicide utilization. The bursting of reactive oxygen species (ROS) is a common defense response of host plants to pathogenic infections. In this study, ROS-responsive mesoporous silica nanoparticles (MSN) modified with phenyl sulfide (PHS) as azoxystrobin (AZOX) carrier (MSN–PHS–AZOX) were fabricated. Results demonstrated that MSN–PHS–AZOX exhibited fungicide release kinetics dependent on ROS. In vitro inhibition experiments confirmed the fungicidal effect of MSN–PHS–AZOX on Botrytis cinerea, relying on external ROS. In vivo leaf experiments showcased the superior persistence of MSN–PHS–AZOX in compared to AZOX SC. Furthermore, MSN–PHS–AZOX exhibits favorable biosafety and lower toxicity to aquatic zebrafish compared to AZOX SC, with no adverse impact on cucumber leaf growth. These findings suggest the potential application of this ROS-responsive nano fungicide in managing plant disease in agricultural fields.