School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
College of Science, Huazhong Agricultural University, Wuhan 430070, China.
Molecules. 2022 Oct 15;27(20):6916. doi: 10.3390/molecules27206916.
Nicotine hydrochloride (NCT) has a good control effect on hemiptera pests, but its poor interfacial behavior on the hydrophobic leaf leads to few practical applications. In this study, a vesicle solution by the eco-friendly surfactant, sodium diisooctyl succinate sulfonate (AOT), was prepared as the pesticide carrier for NCT. The physical chemical properties of NCT-loaded AOT vesicles (NCT/AOT) were investigated by techniques such as dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). The results showed that the pesticide loading and encapsulation efficiency of NCT/AOT were 10.6% and 94.8%, respectively. The size of NCT/AOT vesicle was about 177 nm. SAXS and surface tension results indicated that the structure of the NCT/AOT vesicle still existed with low surface tension even after being diluted 200 times. The contact angle of NCT/AOT was always below 30°, which means it could wet the surface of the cabbage leaf well. Consequently, NCT/AOT vesicles could effectively reduce the bounce of pesticide droplets. In vitro release experiments showed that NCT/AOT vesicles had sustained release properties; 60% of NCT in NCT/AOT released after 24 h, and 80% after 48 h. Insecticidal activity assays against aphids revealed that AOT vesicles exhibited insecticidal activity and could have a synergistic insecticidal effect with NCT after the loading of NCT. Thus, the NCT/AOT vesicles significantly improved the insecticidal efficiency of NCT, which has potential application in agricultural production activities.
盐酸烟碱（NCT）对半翅目害虫有较好的防治效果，但由于其在疏水叶片上的界面行为较差，实际应用较少。本研究采用生态友好型表面活性剂二异辛基琥珀酸磺酸钠（AOT）制备囊泡溶液作为 NCT 的农药载体。采用动态光散射（DLS）、小角 X 射线散射（SAXS）和低温透射电子显微镜（cryo-TEM）等技术研究了负载 NCT 的 AOT 囊泡（NCT/AOT）的物理化学性质。结果表明，NCT/AOT 的载药量和包封率分别为 10.6%和 94.8%。NCT/AOT 囊泡的粒径约为 177nm。SAXS 和表面张力结果表明，即使在稀释 200 倍后，NCT/AOT 囊泡的结构仍然存在，表面张力较低。NCT/AOT 的接触角始终低于 30°，这意味着它可以很好地润湿白菜叶片的表面。因此，NCT/AOT 囊泡可以有效降低农药液滴的反弹。体外释放实验表明，NCT/AOT 囊泡具有持续释放特性；NCT/AOT 中的 60%的 NCT 在 24 h 后释放，80%在 48 h 后释放。对蚜虫的杀虫活性测定表明，AOT 囊泡具有杀虫活性，负载 NCT 后与 NCT 具有协同杀虫作用。因此，NCT/AOT 囊泡显著提高了 NCT 的杀虫效率，在农业生产活动中有潜在的应用前景。
