PDF《吡唑醚菌酯 / 二氧化硅微球的释放行为与生物活性评价》

? 研究论文 ? DOI: 10.

16801/j.issn.1008-7303.2018.0065 吡唑醚菌酯/二氧化硅微球的释放行为与生物活性评价 王娅1,2 , 王昱翔1,2 , 张盈1,2 , 张星1,2 , 陈伟1,2 , 李晓刚*,1,2 (1. 湖南农业大学 植物保护学院,南方粮油作物协同创新中心,长沙 410128;

2. 农业有害生物预警与防控湖南省工程研究中心,长沙 410128) 摘要:为了对二氧化硅载药体系进行评价,以吡唑醚菌酯为模式农药,利用其与正硅酸乙酯 在碱性条件下的水解缩合反应,以十六烷基三甲基溴化铵 (CTAB) 为模板剂,制备了吡唑醚菌 酯/二氧化硅微球.通过扫描电子显微镜、Nicolet iS5 傅里叶变换红外光谱及高效液相色谱等表 征了微球的表面形态和化学结构,测定了其在水中的光解速率;

并采用透析袋法探讨了该微球 在不同 pH 值和不同温度下的缓释行为,通过菌丝生长速率法测定了该微球对稻瘟病菌的毒 力,评价了其生物活性.结果表明:所制备的吡唑醚菌酯/二氧化硅微球外观形貌较为规整,粒 径在 0.998~1.428 μm 之间,其最大载药量可达 50.73%.该微球在碱性条件下的释药速率快于 酸性条件下,且其释放均符合一级反应动力学方程,在中性条件下其释药符合 Ritger-Peppas 方程;

与pH 值相比,温度对其释药速率的影响较小.给药后第

5 天,所制备吡唑醚菌酯/二氧化 硅微球的毒力与原药相近,给药后第

9 天,其毒力是原药的 11.7 倍,缓释效果显著.该吡唑醚菌酯/ 二氧化硅微球在紫外灯照射

10 h 后光解率为 38.98%,明显低于吡唑醚菌酯原药的光解率 (68.92%). 关键词: 吡唑醚菌酯;

二氧化硅;

微球;

释放动力学 ;

控释;

缓释;

稻瘟病菌;

生物活性 中图分类号:TQ 450.68 文献标志码:A 文章编号:1008-7303(2018)04-0506-08 Release behavior and bioactivity evaluation of pyraclostrobin/silica microspheres WANG Ya1,2 , WANG Yuxiang1,2 , ZHANG Ying1,2 , ZHANG Xing1,2 , CHEN Wei1,2 , LI Xiaogang*,1,2 (1. College of Plant Protection, Hunan Agricultural University, Southern Regional Collaborative Innovation Center for Grain and Oil Crops, Changsha 410128, China;

2. Hunan Provincial Engineering Research Center for Agricultural Detrimental Organism Early Warning and Prevention, Changsha 410128, China) Abstract: In order to evaluate the silica drug-loading system, the pyraclostrobin/silica microsphere was prepared by the hydrolysis and polycondensation of tetraethyl orthosilicate under alkaline conditions with pyraclostrobin as the pattern pesticide. The surface morphology and the chemical structure of the microsphere were characterized by scanning electron microscope (SEM), Nicolet iS5 Fourier transform infrared spectrometer (FTIR) and high performance liquid chromatography (HPLC). And its photodegradation rate in water was also determined.The release behavior under different pH/temperature was studied by dialysis bag method. And the growth rate method was employed to 农药学学报 2018, 20(4): 506-513 Chinese Journal of Pesticide Science http://nyxxb.alljournal.cn 收稿日期:2018-03-12;

录用日期:2018-06-12. 基金项目:化学肥料和农药减施增效综合技术研发专项 (2016YFD0201200);

湖南省高校重点实验室平台开放基金 (15K064). 作者简介:王娅,女,在读硕士研究生,E-mail:15211062742@163.com;

* 李晓刚,通信作者 (Author for correspondence),男,博士, 教授,主要从事农药低毒化应用技术研究,E-mail:lxgang@hunau.edu.cn study the virulence against Pyricularia oryzae. The results showed that the pyraclostrobin/silica microsphere exhibited regular appearance with the maximum drug loading of 50.73% and the average particle size of 0.998-1.428 μm. Release property was tested under different pH. The results indicated that the release rate of microspheres under alkaline conditions was greater than that of acidic conditions. In addition, the release rates under both acidic and basic conditions were consistent with the first order kinetics equation. And the release in accordance with the Ritger-Peppas equation in the neutral condition. Compared with pH, temperature had little effect on the release rate. The effect of pyraclostrobin/silica microspheres on the fifth day after administration was similar to that of the technical concentrate, while the virulence on the ninth day after administration was 11.7 times higher than that of the technical concentrate, which indicated that the sustained-release effect of pyraclostrobin/ silica microspheres was significant. The photodegradation rate of microsphere was 38.98% after