【摘要】 为了减少甲维盐的用量及其对环境的影响，利用溶剂扩散法制备甲维盐纳米颗粒，并通过静电作用在颗粒表面包覆海藻酸得到纳米缓释剂，利用傅里叶变换红外光谱、动态光散射和透射电镜分析工艺条件下甲维盐@海藻酸纳米颗粒的结构对甲维盐释放特征的影响。结果表明：甲维盐@海藻酸纳米颗粒的粒径D_h和ζ-电位负值随着海藻酸用量的增加而增大，但是Ca²⁺的交联作用将导致D_h和ζ-电位负值减小。甲维盐负载与海藻酸、CaCl₂浓度有关，增大海藻酸、CaCl₂的浓度有利于提高甲维盐的包封率P_EE,但减小了甲维盐在纳米颗粒中的载药率P_LE。海藻酸包覆延缓了甲维盐的释放，其释放速率主要受到活性分子与基材的相互作用的影响。Ca²⁺与海藻酸羧基的静电结合削弱了甲维盐与海藻酸的相互作用，加快了甲维盐的扩散释放，而碱性介质中海藻酸分子与甲维盐之间的相互作用因羧基解离度的增大而增强，具有较好的缓释性能。更多还原

【Abstract】 In order to reduce the use and impact of emamectin benzoate（EB） on the environment, nanoparticles were prepared by solvent diffusion method and coated with alginate（Alg） via electrostatic binding. The structure of the nanoparticles was characterized by FTIR, DLS and TEM, and related to the release behavior of EB. The results indicated that the size and the negative values of ζ-potential of EB@Alg nanoparticle increase with increasing Alg content, but decrease due to the crosslinking of the polymer chains by Ca²⁺cations. The increase of Alg and Ca²⁺ benefit the encapsulation of EB, however leading to a lower loading efficiency in the nanoparticles. The release of EB is generally retarded by encapsulating into Alg-based nanoparticles and greatly influenced by the interaction with the polymer matrix. Competition binding of Ca²⁺cations on the polymer chains of Alg reduces the electrostatic interaction with EB and increases the diffusional release from the matrix. A better sustaining efficiency is obtained in the basic medium, due to the enhanced interaction with the active ingredient induced by the increased dissociation of carboxyl groups of Alg.更多还原