Utilization of Chitosan-Lactide Copolymer Nanoparticles as Controlled Release Pesticide Carrier for Pyraclostrobin Against Colletotrichum gossypii Southw

Abstract

Low effective availability of modern pesticides places heavy burdens on both the environment and costs to farmers. Nano-augmented delivery systems seem to be more promising to address the present challenge modern pesticides are facing. In this article, biodegradable chitosan-lactide copolymer (CPLA) was prepared and characterized as hydrophobic pesticide-pyraclostrobin carrier. Nano-precipitation method was used to fabricate pyraclostrobin-loaded nanoparticles. Loading content (LC), encapsulation efficiency (EE), size, and size distribution of the resulting nanoparticles were investigated. The size of pesticide-loaded nanoparticles can be adjusted between 77 to 128 nm by varying the feed mass ratio of copolymer to pyraclostrobin from 50/1 to 5/1. Compounds contained within nanoparticles was protected from light compared with the technical material. The pyraclostrobin-loaded nanoparticles showed an initial burst, subsequent sustained and pH-controlled release profile. Compared to 25% pyraclostrobin emulsifiable concentrate (EC), the nanoparticles demonstrated better fungicidal activity against Colletotrichum gossypii Southw under long incubation time, which further exhibited sustained release characteristic.

Keywords:

• Chitosan
• fungicidal activity
• nanoparticles
• pyraclostrobin
• sustained release

Notes

L. Xu and L.-D. Cao contributed equally to this work.

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