【作者】 姜建芳；

【导师】 崔海信；

【作者基本信息】 中国农业科学院 ， 生物物理学， 2014， 博士

【摘要】 农药是防御重大生物灾害，保障粮食生产，促进农产品产量持续稳定增长的重要物质。目前我国农药制剂发展较快，但仍以传统剂型为主，有效利用率低，农药残留与环境污染也非常严重。农药污染造成的食品安全、健康风险与生态环境问题，已经成为国民密切关注的社会问题。水基化、无尘化、控制释放等成为农药新剂型的发展方向。海藻酸钙凝胶是一种天然生物多糖，具有生物相容性和生物粘连性好、孔隙结构丰富、负载能力强、化学性能稳定、制备方法温和、来源广泛、价格低廉等特性，将药物包埋或镶嵌在其孔隙中，既可延长药物释放作用时间，又能阻止药物与周边环境的接触，防止敏感性药物降解，提高药物稳定性。采用先进的纳米材料制备与加工技术，制备高效、安全的纳米缓控释农药新剂型，是减少农药环境污染，保障人民健康，促进农药产业可持续发展的重要途径。本论文根据农药理化性质的差异，开拓性的对海藻酸钙纳米囊（CANC）、阿维菌素纳米混悬液（ANS）、缓控释井冈霉素纳米囊（CRVNC）和Zn3P2/海藻酸钙纳米囊（NC-Zn3P2/CA）进行了研究，为农药新剂型的开发提供先进的思路和方法。结果表明：（1）以海藻酸钠与CaCl2为原料、溴化十六烷基三甲铵（CTAB）为表面活性剂、异丙醇为助表面活性剂，采用W/O型反相微乳聚合法，制备了CANC。该CANC呈规则球形，粒径分在130-480nm之间，平均粒径为252±16nm，粒子分散系数（PDI）为0.222，比表面积（BET）为260m2·g-1，在其表面与内部有大量的孔隙，平均孔径为6.2nm。海藻酸钠溶液、CTAB、异丙醇三种物质的加入量对其BET均有显著影响。（2）以井冈霉素作为亲水性药物代表，以海藻酸钠与CaCl2为合成原料，通过聚合反应，对井冈霉素进行包埋，制备了平均粒径为281±18nm、PDI为0.082的CRVNC。井冈霉素原药和海藻酸钠的加入量对其负载效果和缓控释性能有显著影响。该CRVNC在水中具有明显的“突释现象”，对立枯丝核菌具有很好的抑制作用，抑菌率随井冈霉素有效浓度的提高而增大。在较短的时间内，CRVNC对立枯丝核菌的作用效果弱于井冈霉素原药，但随着试验时间的延长，CRVNC体现出缓控释性能的优越性，抑菌效果逐渐超过井冈霉素原药。（3）以Zn3P2作为既非亲水性又非疏水性药物代表，利用现代纳米加工技术，在反相微乳液中通过聚合反应，制备了粒径分布在220-580nm之间，平均粒径为354±23nm，PDI为0.195的NC-Zn3P2/CA。与Zn3P2原药相比，该NC-Zn3P2/CA无臭无味，大幅度改善了适口性和药效，其摄食系数提高了1.2-2.3倍，毒杀效果提高了4倍。缓控释测试表明，NC-Zn3P2/CA具有“突释现象”，海藻酸钙与Zn3P2的质量比（mCA/mZn3P2）对NC-Zn3P2/CA的载药率和缓控释性能均具有显著影响。当mCA/mZn3P2为1︰2时，NC-Zn3P2/CA对Zn3P2的负载达到了饱和。（4）以阿维菌素原药为疏水性药物代表、亚甲基二萘磺酸钠（NNO）为分散剂、海藻酸钠为助悬剂、二甲基聚硅氧烷为消泡剂、聚甲氧基聚氧乙烯甲基丙烯酸酯为稳定剂，使用砂磨机，通过湿法研磨，制备ANS。该ANS呈不规则球形，澄清，半透明，在水中均匀分散，平均粒径为586±20nm，表面Zeta电位为-19.5mV，且具有良好的悬浮性能和热稳定性能。研磨时间、阿维菌素原药与NNO的加入量对ANS的粒径有一定的影响。本论文研究证实，采用现代纳米加工技术，制备水基化的农药纳米混悬液或缓控释农药纳米囊等农药新剂型，既可提高农药的生物活性与利用率，又可减少各种有机溶剂与表面活性剂的使用量，对于缓解环境污染，维护生态平衡，促进绿色农业发展具有重要意义。更多还原

【Abstract】 Pesticides are important materials for defending major biological disasters, safeguarding grainproduction and promoting agricultural output steady growth. Pesticide formulations are still based ontraditional dosage forms, in spite they’are rapidly developing in our country, and the effective utilizationof pesticides is generally low. There’re very serious pesticide residues and environmental pollution.People pay close attention to food safety, health risks and ecological environment problems, which arecaused by pesticide pollution. Water-based, dust-free and controlled-release dosage forms become thedevelopment direction of new pesticide formulations.Calcium alginate gel is a kind of natural biological polysaccharide, and has good biocompatibilityand biological adhesion, rich pore structure, strong loading capacity, stable chemical performance, mildpreparation method, wide source and low price. It can prolong the acting time of pesticides release, andprevent sensitive pesticides degradation through stopping pesticides contacting with the surroundingenvironment after they are embedded or inlaid in the pores of calcium alginate gel. Therefore, it canenhance the stability of pesticides. Using advanced nano-materials and nano-technology to produce newnano controlled-release pesticide formulations, which are efficient and safe, is an important way toreduce environment pollution, protect people’s health, and promote sustainable development ofpesticide industry. According to the different physical and chemical properties of pesticides, we firstlyconducted a study on calcium alginate nanocapsules (CANC), abamectin nanosuspension (ANS),controlled-release validamycin nanocapsules (CRVNC) and Zn3P2/calcium alginate nanocapsules(NC-Zn3P2/CA), in order to provide an advanced idea and method to research on new pesticideformulations.The results showed that:(1) CANC are synthesized by W/O reverse microemulsion polymerizationmethod, using sodium alginate and CaCl2as raw materials, cetyltrimethyl ammonium bromide (CTAB)as a surfactant and isopropanol as a cosurfactant. They are good globular, and particle size distributesbetween130nm to480nm, average particle size is252±16nm, particle dispersion index (PDI) is0.222,specific surface area (BET) is260m2·g-1. There’re a large number of pores distributing in the interior ofCANC, and the average pore size is6.2nm. The content of sodium alginate solution, CTAB andisopropyl alcohol has a significant effect on BET of CANC.(2) CRVNC is prepared by embedded through polymerization reaction using sodium alginate andCaCl2as raw materials, and the average particle size is281±18nm, PDI is0.082. Loading effect andcontrolled-release performance are significantly influenced by the addition amount of validamycintechnical and sodium alginate. It has an obvious sudden release phenomenon in water, and there’s avery good inhibitory effect to rhizoctonia solani. Antibacterial rates increase with the increase ofvalidamycin effective concentration. Antibacterial effect of CRVNC on rhizoctonia solani is weakerthan validamycin technical in a relatively short period of time. As prolonging test time, CRVNC startsto reflect superiority of controlled-release, and antibacterial effect of CRVNC on rhizoctonia solani is better than validamycin technical, gradually.(3) NC-Zn3P2/CA is synthesized by inverse microemulsion polymerization method using modernnano processing technology. The particle size distribution is between220nm to580nm, averageparticle size is354±23nm, and PDI is0.195. They are odourless and tasteless, palatability andpharmaceutical efficacy are greatly improved and enhanced, and the ingestion index increased1.2timesto2.3times, killing rate increased4times, compared with Zn3P2technical. There’re obvious suddenrelease phenomenons for NC-Zn3P2/CA. The mass ratio of calcium alginate and Zn3P2(mCA/mZn3P2) hasa significant impact on loading rate and controlled-release performance of NC-Zn3P2/CA. Loadingcapacity of Nano-Zn3P2/CA to Zn3P2reached the saturation point, when the mCA/mZn3P2is1:2.(4) ANS is produced by using sand mill through wet grinding, using methylene naphthalenesulfonate (NNO) as a dispersant, dimethyl polysiloxane as a defoaming agent, poly methoxypolyoxyethylene methyl acrylate as a stabilizer, sodium alginate as a suspension agent. It’s irregularspherical, clear, translucent, evenly dispersed in the water, and the average particle size is586±20nm.There’re some negative charges on the surface, and the surface Zeta potential is-19.5mV. It has a goodsuspension performance and thermal stability. Milling time, and the addition amount of abamectintechnical and NNO have certain impacts on particle size of the ANS.These studies confirmed that using modern nanomanufacturing technology to prepare water-basedpesticide formulations, such as pesticide nanosuspension and controlled-release pesticide nanocapsules,which can raise biological activity and utilization of pesticides, and reduce the usage of various organicsolvent and surfactant. It has a great significance to alleviate environment pollution, maintain ecologicalbalance, and promote the development of green agriculture.更多还原