Study On Sustained-release Gel Of Botanical Pesticide-matrine

The larva of Bradysia odoriphaga is a kind of underground pest that seriously endanger the growth of Amaranth.The problem caused by chemical control was increasingly ignored.In order to complying with the requirements of green agricultural development,botanical pesticide-Matrine was selected as the target drug and Amaranth was selected as the target pest in this study.Sustained-release technology was used to prepare a sustained-release gel compound of Matrine that can be released slowly in the soil with the number of irrigation.The paper was divided into five parts.The formulation process and the structure of sustained-release gel compound of Matrine were studied in the first part.The best process was investigated by Response surface methodology,the structure and characterization were investigated by Microscope,Scanning electron microscope,Differential thermal analysis and Infrared spectroscopy.The results showed that the preparation process of sustained-release gel compound of Matrine was simple and the sustained release effect was better.The ratio of Matrine to ?-cyclodextrin was 1:10.58,the heating temperature was 61?,the stirring time was 18 min,the concentration of Carbomer 941 was(4.85-5.21)% and the ratio was 2.50:1.A new physical crystallization was formed between Matrine and excipients,chemical structure of Matrine had not been changed.The release kinetics of preparations were studied in the second part.The static process and dynamic process of field irrigation were simulated and the drug release kinetic model was fitted.The results showed that the ?-cyclodextrin preparation conformed to the first-order kinetic release law and the release of sustained-release gel compound of Matrine conformed to the Higuchi release law.The ?-cyclodextrin preparations conformed to diffusion release and the sustained-release gel compound of Matrine was released through the synergistic action of diffusion and dissolution.The quality inspection system of the preparation was established in the third part.The performance,particle size,pH,viscosity and loading of the gel preparation were established.UV and HPLC were established to analysis the content of Matrine.The results showed that the indexes of the sustained-release gel compound conformed to the requirements of the Chinese Pharmacopoeia(2015).The precision,stability and recovery rate of two analytical methods were perfect and the test results were accurate and reliable.UV was convenient and HPLC was more sensitive.The stability of the preparation was studied in the fourth part.The effect of high temperature,high humidity and strong light on the stability of the preparation were examined to select the best packaging material and preservative.Accelerated and long-term stability tests were used to investigate various indicators of the preparation.The results showed that PVC hose was the best packaging material,the stability of the formulation can be improved by preservative.In the accelerated test and long-term stability test,the indicators were within the normal range and the preparation was preferentially stored at low temperature(4±2?).The effect of soil on the degradation of Matrine and the preliminary study of insecticidal effect in experimental field were studied in the fifth part.The results showed that the half-life of Matrine in the sustained-release gel compound was approximately 20 days,and it was longer than the half-life of Matrine monomer.The use cycle of the gel compound preparation can cover the whole growth period of the leek.The insecticide effect of the gel compound preparation was significant.This project conforms to the requirements of the development of green agriculture and the concept of sustainable development.The study has developed a sustained release of plant-derived pesticide Matrine for the first time and the release of the sustained-release gel compound of Matrine can cover the entire growth cycle of leek,the preparation process of the sustained-release gel compound is simple and the release is regular.This is a new method which applys medical preparations to agronomy and provides new ideas for the research of sustained-release preparation of plant-derived pesticide.