两亲性壳聚糖自组装纳米微球的制备及抗真菌性能研究

Preparation and Antifungal Properties of Self-assembledAmphiphilic Chitosan Nanocapsules

通过两步法反应将桐油酸(EA)和N-乙酰-L-半胱氨酸(NAC)接枝壳聚糖(CS)制备两亲性壳聚糖(CS-g-EA-NAC),并通过红外光谱、核磁氢谱对其结构进行表征分析。然后采用超声波自组装法制备了负载多杀菌素(Spinosad,SSD)的载药纳米粒子(SSD@CS-g-EA-NAC)。最后通过生长速度法测定了SSD@CS-g-EA-NAC和SSD对尖孢镰刀菌的抗菌性能。结果表明,载药纳米粒子呈球形,粒径分布均匀,平均粒径约为520 nm,同时载药纳米粒子具有良好的缓释性能和pH响应性能。抑菌实验显示,载药纳米粒子(SSD@CS-g-EA-NAC)和SSD对尖孢镰刀菌的半数有效浓度(EC 50)分别是29.05μg/mL和42.05μg/mL,这表明SSD@CS-g-EA-NAC毒力高于游离的SSD,纳米粒子(CS-g-EA-NAC)有助于提高SSD的毒力性能。该研究可为壳聚糖基载药体系的构建提供理论依据。

In this paper,eleostearic acid(EA)and N-acetyl-L-cysteine(NAC)were grafted to the chain of chitosan(CS)to prepare an amphiphilic chitosan derivative(CS-g-EA-NAC),and the chemical structure of CS-g-EA-NAC was characterized by Fourier transform infrared(FT-IR)and 1H nuclear magnetic resonance(1H NMR).Then,CS-g-EA-NAC based nanoparticles were prepared by ultrasonic self-assembly method,and the spinosad(SSD)loaded nanocapsules(SSD@CS-g-EA-NAC)were spherical in shape with a uniform particle size distribution,and the average particle size was about 520 nm.In vitro release revealed that the SSD@CS-g-EA-NAC nanocapsules exhibited a sustained and pH-responsive drug release property.Finally,the antifungal properties of SSD@CS-g-EA-NAC and SSD against Fusarium oxysporum were determined by the growth rate method.The results showed that the half effective concentration(EC 50)of SSD@CS-g-EA-NAC and SSD against Fusarium oxysporum was were 29.05μg/mL and 42.05μg/mL,respectively,indicating that the virulence of SSD@CS-g-EA-NAC is higher than that of free SSD,and the conjugate CS-g-EA-NAC is conducive to improve the virulence of SSD.This research can provide a theoretical basis for the construction of chitosan-based drug delivery system.