Construction And Characterization Of Camptothecin Nano Drug Delivery System

Agricultural bio-disasters occur frequently in China,and traditional pesticide formulations have brought about a series of environmental safety issues when ensuring food security.Camptothecin(CPT)has infertility and toxic effects on pests,has antibacterial activity against more than ten kinds of pathogenic bacteria,and has broad development prospects.Therefore,using camptothecin as the original drug to study the construction of its nano drug-loading system can effectively improve the use rate of pesticides,reduce environmental pollution,and have obvious ecological,economic and social benefits.In order to solve the problem that camptothecin is insoluble in water and improve the utilization rate of pesticides,this paper studies the preparation method of camptothecin nano drug-loading system,and uses surface tannin to modify its surface on plant leaves.Adhesion.The results obtained are mainly as follows:1.The preparation of camptothecin nano drug-loading system was carried out by emulsion cross-linking method.The nano drug-loading system was developed with a smooth spherical shape with an average particle size of 900 nm,which was drawn by HPLC.The standard curve was calculated to give a drug loading of 44%and an entrapment efficiency of 56.1 1%.The construction of the camptothecin nano drug-loading system can significantly improve the problem that the camptothecin drug is poorly soluble in water.2.Tanninic acid was used to modify the surface of camptothecin nanometer drug-loading system to increase its adhesion on the foliage of plants.The average particle size was 650nm.The image obtained by scanning electron microscope showed that the nanometer drug-loading system showed a smooth surface Ball type.The stability of camptothecin was improved,and its retention on plant leaves by HPLC was:tannic acid/camptothecin nano drug-loading system(75%)>camptothecin nano-drug loading system(56%)>The camptothecin drug(40%)can effectively increase its adhesion on the foliage of plants3.Toxicity of camptothecin nano drug-loading system to Bursaphelenchus xylophilus was measured by dipping method.The experimental results show that the insecticidal activity of the tannic acid/camptothecin nano drug-loading system(98.33%)is greater than the insecticidal activity of the camptothecin nano-drug-loading system(90.48%)The toxicity of camptothecin nano-loading system to 3-4 instar larvae of Plutella xylostella was determined by leaf dipping method.The experimental results show that the insecticidal activity of the camptothecin nanometer drug-loaded system against Plutella xylostella(45%)when the configured solution concentration is 1000mg/mL>Tannic acid/camptothecin nanometer drug-loaded system against Plutella xylostella Insect activity(38.10%)>Insecticidal activity of the original camptothecin against Plutella xylostella(35%).The camptothecin nano-loading system and tannic acid/camptothecin nano-loading system have better toxicity to 3-4 instar larvae than Plutella xylostella.The preparation of camptothecin nano drug-loading system can improve the problem of insoluble camptothecin in water,thereby increasing the utilization rate of pesticides and increasing the safety to the environment;adding tannic acid for surface modification and increasing leaf adhesion.At the same time,from the bioassay results,it shows that the toxic effect on Bursaphelenchus xylophilus is good,which has certain significance for the development of efficient and safe new green pesticide formulations.