Fabrication of a controlled-release delivery system for pesticides using carbon dioxide-based copolymer microcapsules

The pH-responsive pesticide delivery system can enhance utilization efficiency of pesticides and reduce environmental pollution. Herein, an environmental and amphiphilic carbon dioxide-based copolymer , poly(propylene oxide-co-carbon dioxide-co-allyl glycidyl ether)-poly(polyacrylic acid)-methoxy poly(ethylene glycol) (PPAG-PAA-mPEG), was synthesized to fabricate a pH-responsive pesticide delivery system. The avermectin (AVE) was selected as a model drug to show PPAG-PAA-mPEG potential as a controlled-release pesticide system. The entrapment efficiency and the loading content of the AVE-loaded micelles was 88.6 % and 36.98 %, respectively. The AVE-loaded micelles were stable. The release rate of AVE gradually increased with the increase of pH. Pot trial showed that the AVE-loaded micelles showed a good pesticidal efficacy. Because of CO 2 as raw materials, and excellent pH-responsive controlled-release performance, these on-demand pesticide delivery systems might have significant potential in improving the utilization efficiency of pesticides in modern agriculture.