Chlorpyrifos-Loaded Attapulgite/Sodium Alginate Hybrid Microsphere and its Release Properties

With Ca 2+ ions as cross-link agent, chlorpyrifos-loaded attapulgite/sodium alginate hybrid microspheres were prepared by extrusion method. The hybrid microspheres were characterized by FITR, DSC, SEM techniques to gain insights into the structural and morphological features of the microspheres. Meanwhile, the release properties of the drug-loaded hydrogel microspheres for chlorpyrifos were tested. The experimental results indicate that, chlorpyrifos were loaded in calcium alginate microspheres in the forms of partial differential aggregation and molecular disperse, and there exists hydrogen bond between sodium alginate and attapulgite. The release effect of hybrid gel microspheres for chlorpyrifos can be divided into two stages, namely, the burst release and the sustained release. With the increasing of the attapulgite content, the release rate during the sustained-release phase and the amount of pesticide during burst release will be significantly reduced. The introduction of attapulgite can change the micro-phase structure of the drug-loaded sodium alginate gel, which is conducive to improve the release effect of gel microspheres for pesticides, thus promoting the release performance of drug-loaded sodium alginate microspheres.