新型两亲性多糖基戊唑醇纳米胶囊的制备及缓释性能研究

Preparation and sustained-release performance of novel amphiphilic polysaccharide-based tebuconazole nanocapsules

以羧甲基纤维素钠（CMC-Na）为原料,通过离子液体活化法使其与生育酚琥珀酸酯进行酯化反应,制备新型两亲性多糖基材料羧甲基纤维素钠衍生物（CMCD）,并利用傅里叶红外光谱（FTIR）、核磁共振波谱（^1H NMR）、X-射线衍射（XRD）及热重（TG）分析表征其分子结构及热性能;采用超声/溶剂挥发法制备载戊唑醇CMCD纳米胶囊,并通过动态光散射（DLS）和透射电镜（TEM）测定该纳米胶囊的粒径及形貌,采用高效液相色谱法测定包封率、载药量及缓释性能;利用培养基法探究其抑菌效果。结果表明：成功合成了两亲性CMCD,其临界胶束浓度（CAC）为0.28 mg/mL;所制备的戊唑醇纳米胶囊的粒径为400~500 nm,包封率为50.8%,载药量为40.4%;缓释及抑菌试验结果显示,所制备的纳米胶囊48 h的最终累积释药率仅为77.78%,施药后12 d对山核桃干腐病菌菌丝生长的抑制率仍可达17.67%,而此时传统的戊唑醇悬浮剂（430 g/L）的抑制率已为0%。表明所制备的新型两亲性多糖基戊唑醇纳米胶囊具有良好的缓释性能及抑菌效果。

Novel amphiphilic polysaccharide-based material carboxymethyl cellulose derivative（CMCD） was prepared by esterification of carboxymethyl cellulose sodium（CMC-Na） and tocopherol succinate via ionic liquid activation. The FTIR, ^1 H NMR, X-ray diffraction（XRD） and thermogravimetry（TG） were used to characterize the molecular structure and thermal properties. The tebuconazole nanocapsules were prepared using ultrasound/rotary evaporation. The particle sizes and morphologies of the nanocapsules were determined by dynamic light scattering（DLS） and transmission electron microscopy（TEM）. The entrapment efficiency, loading rate and sustained-release performance of tebufonzol were detected by HPLC, and the fungicidal activity was also investigated using the medium method. The results showed that the amphiphilic carboxymethyl cellulose derivative（CMCD） was successfully synthesized with the critical micelle concentration（CAC） of 0.28 mg/mL. The particle size of the tebuconazole nanocapsules was 400-500 nm, the encapsulation efficiency was 50.8%, and the drug loading was 40.4%. The sustained-release test showed that, after 48 hours, the final cumulative release rate of tebuconazole-loaded CCMD nanocapsules was 77.78%. The bioassay results showed that the inhibition rate of the tebuconazole-loaded CMCD nanocapsules against Botryosphaeria dothidea still reached 17.67% after 12 days. At this time, the inhibition rate of the traditional tebuconazole 430 g/L SC was almost 0. The research indicated that the novel amphiphilic polysaccharide-based tebuconazole nanocapsules prepared in this work have good sustained-release performance and fungicidal activity.