农药纳米微囊化剂型研究进展

Research Progress on Nanocapsules Formulations of Pesticides

农药是保障国家粮食安全的重要物质基础,由于使用量较大,加之农药有效利用率低,造成环境污染、农产品残留超标、作物药害等问题,提高农药有效利用率是国家重大战略需求。农药微胶囊化剂型具有控制释放、降低毒性和抗光解的优势,可以有效改善农药利用率,降低残留与污染,但目前多集中在微米量级,纳米微囊化剂型由于小尺寸效应和大比表面积,在提高农药叶面积沉积与展布、增强生物活性方面具有明显的优势,所以其制备技术与产业化放大是目前的一大挑战。着重分析了农药纳米微囊化技术的现状、特点与发展,并对各种方法的制备原理、适用条件、优缺点及存在的问题进行了详细的论述,但是现在的制备方法仍存在对功效成分的包覆率低、无法精确控制纳米囊的粒径大小、均匀度以及停留在实验室水平上等问题,因此,针对不同农药的理化性质和载药体系,探索一种温和、可量产化的农药纳米微囊生产方式是未来的发展方向。

Pesticide is an important material basis for national food security. Due to the heave usage of pesticide and its low effective utilization rate, serious problems of environmental pollution, excessive pesticide residues of agricultural products,crop phytotoxicity,etc. were occurred. So,improving the effective utilization rate of pesticides is a great strategic demand for the country. The microcapsule pesticide formulations possess the advantages of controlling release, reducing toxicity, preventing light degradation, etc., which could improve the effective availability of pesticides and reduce residue and pollution. But at present,the research of microcapsules mostly focus on micro-scale,as the result of nanocapsules have the properties of small size and large specific surface,so it has conspicuous advantages in improving deposition and distribution in leaves and enhancing bioactivity. To prepare nanoscale microcapsule is a big challenge of technology,this paper analyzed the current situation,features and development of nanocapsules in pesticides,and also discussed manufacturing principle,application conditions,merits and demerits,and exisiting problems in detail. However,the preparation methods still have low coverage rate for the functional components,and can not precisely control the size,uniformity of the nanocapsules,and remain at the laboratory level. Therefore,in view of the different physicochemical property and drug delivery system of pesticides,exploring a gentle and mass-produced method to prepare pesticide nanoparticles is the future development direction.