嘧草醚固体分散体的制备、表征及除草活性研究

Preparation,Characterization and Herbicidal Activity of Pyriminobac-methyl Solid Dispersion

为了制备嘧草醚固体分散体,研究不同载体对嘧草醚的增溶效果、溶出特性及除草活性的影响,本研究利用PEG-4000、PEG-6000、PVP-K30,采用溶剂-熔融法和溶剂法制备嘧草醚固体分散体,采用HPLC测定固体分散体的体外溶出度,筛选出最佳载体及药载比,并通过傅里叶变换红外光谱(FT-IR)、X射线粉末衍射(XRD)、扫描电镜(SEM)对固体分散体结构进行表征,并采用盆栽法测定嘧草醚固体分散体对稗草的生物活性。结果表明,以上3种载体均可不同程度地提高嘧草醚的体外溶出,其中以PVP-K30为载体、药载比为1∶6的固体分散体溶出度最高;药后7、15 d,嘧草醚-PVP-K30固体分散体对稗草的生物活性高于嘧草醚可湿性粉剂。

In order to prepare pyriminobac-methyl solid dispersionand and study effects of different carriers on its solubilizing effect,dissolution characteristics and herbicidal activity,PEG-4000,PEG-6000 and PVP-K30 were used to prepare the solid dispersion of pyriminobac-methyl by solvent-melt method and solvent method.The dissolution of pyriminobac-methyl from the system of solid dispersion was measured by HPLC,and the best carrier and drug loading ratio were screened out.The structure of solid dispersion was characterized by fourier transform infrared spectroscopy(FT-IR),X-ray powder diffraction(XRD)and scanning electron microscope(SEM).The biological activity of the pyriminobac-methyl solid dispersion on Echinochloa crusgalli was determined by the potted method.The results showed that the above three kinds of carriers could improve the dissolution of pyriminobac-methyl in vitro to varying degrees.Among them,the solid dispersion with the carrier PVP-K30 and drug loading ratio of 1∶6 had the highest dissolution rate.The control effect of pyriminobac-methyl solid dispersion was higher than that of the pyriminobac-methyl wettable powder after 7,15 d of application.