title: Construction of a controlled-release delivery system for pesticides using biodegradable PLA-based microcapsules.
abstract: Conventional pesticides usually need to be used in more than recommended dosages due to their loss and degradation, which results in a large waste of resources and serious environmental pollution. Encapsulation of pesticides in biodegradable carriers is a feasible approach to develop environment-friendly and efficient controlled-release delivery system. In this work, we fabricated three kinds of polylactic acid (PLA) carriers including microspheres, microcapsules, and porous microcapsules for controlled delivery of Lambda-Cyhalothrin (LC) via premix membrane emulsification (PME). The microcapsule delivery system had better water dispersion than the other two systems. Various microcapsules with a high LC contents as much as 40% and tunable sizes from 0.68 to 4.6μm were constructed by manipulating the process parameters. Compared with LC technical and commercial microcapsule formulation, the microcapsule systems showed a significantly sustained release of LC for a longer period. The LC release triggered by LC diffusion and matrix degradation could be optimally regulated by tuning LC contents and particle sizes of the microcapsules. This multi-regulated release capability is of great significance to achieve the precisely controlled release of pesticides. A preliminary bioassay against plutella xylostella revealed that 0.68μm LC-loaded microcapsules with good UV and thermal stability exhibited an activity similar to a commercial microcapsule formulation. These results demonstrated such an aqueous microcapsule delivery system had a great potential to be further explored for developing an effective and environmentally friendly pesticide-release formulation.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics & Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Baoxia
authors.initials: B
authors.lastname: Liu
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academic of Agriculture Sciences, Beijing 100081, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics & Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Yang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics & Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics & Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academic of Agriculture Sciences, Beijing 100081, China. Electronic address: cuihaixin@caas.cn.
authors.forename: Haixin
authors.initials: H
authors.lastname: Cui
authors.affiliation: Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics & Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. Electronic address: dcwu@iccas.ac.cn.
authors.forename: Decheng
authors.initials: D
authors.lastname: Wu
mesh_terms: D001673:Biodegradation, Environmental; D001681:Biological Assay; D002214:Capsules; D003692:Delayed-Action Preparations; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D009570:Nitriles / Q000032:analysis; D010316:Particle Size; D010575:Pesticides / Q000032:analysis*; D010782:Photolysis / Q000528:radiation effects; D011091:Polyesters / Q000737:chemistry*; D011722:Pyrethrins / Q000032:analysis; D014466:Ultraviolet Rays
chemical_list: D002214:Capsules; D003692:Delayed-Action Preparations; D009570:Nitriles; D010575:Pesticides; D011091:Polyesters; D011722:Pyrethrins; C033616:poly(lactide); C037304:cyhalothrin
keywords: Biodegradable; Controlled release; Microcapsule; Thermal-stability; UV-shielding properties; Water dispersion