Glutathione-Responsive Pyraclostrobin-Loaded Polyurea Microcapsules for Their Intelligent Controlled Release

The utilization of intelligent controlled release technology to create stimuli-responsive pesticide formulations hasbeen shown to effectively improve pesticide efficacy and reduce environmental pollution. Herein, a glutathione-responsive releasepolyurea (PU) microcapsules (MCs) loaded with pyraclostrobin were developed via the interface polymerization method. Thepyraclostrobin-loaded PU-MCs showed a regular spherical shape with an average diameter of 480 nm. It also showed good thermalstability and rheological properties. Furthermore, the pyraclostrobin-loaded PU-MCs exhibited favorable wettability on wheat leaves,which was beneficial for enhancing the retention capacity of pesticide droplets and improving pesticide utilization. Thepyraclostrobin can be released from MCs and directly proportional to glutathione (GSH) concentrations with Fickian diffusion.Importantly, the control efficacy of pyraclostrobin-loaded PU-MCs againstFusarium graminearumwas positively correlated withGSH, indicating a promising candidate for a controlled release of pesticides in agriculture and laying the foundation for furtherfieldexperiments.