负载柚皮素的表没食子儿茶素没食子酸酯共价修饰的玉米醇溶蛋白-透明质酸复合纳米颗粒的构建与表征

Fabrication and characterization of naringenin-loaded gallocatechin-gallate covalently modified zein-hyaluronic acid composite nanoparticles

柚皮素具有良好的生物活性和治疗作用,但同时也具有水溶性差、生物利用率低等缺点。因此,建立简单、高效的递送方式对于柚皮素的广泛应用至关重要。该研究通过反溶剂沉淀法制备了负载柚皮素的表没食子儿茶素没食子酸酯(epigallocatechin gallate,EGCG)共价修饰的玉米醇溶蛋白-透明质酸(hyaluronic acid,HA)复合纳米颗粒。与没食子酸和单宁酸共价修饰相比,EGCG修饰后玉米醇溶蛋白具有低游离氨基含量和高多酚当量,修饰效果良好。EGCG共价修饰的玉米醇溶蛋白和HA通过静电作用、氢键和疏水相互作用形成复合纳米颗粒,其粒径在180~240 nm,且当两者质量比为10∶1时,粒径最小(183.62 nm)。由于EGCG的共价修饰,复合纳米颗粒对柚皮素的包埋率和负载能力均明显提高,且在柚皮素与EGCG共价修饰的玉米醇溶蛋白质量比为1∶10或以下时,包埋率>99%。结构表征显示,绝大部分柚皮素被包埋在复合纳米颗粒内部,且与EGCG和玉米醇溶蛋白之间存在氢键和疏水相互作用。抗氧化性测定表明,负载柚皮素的复合纳米颗粒的抗氧化能力显著高于游离柚皮素。因此,采用EGCG修饰的玉米醇溶蛋白-HA体系负载柚皮素对柚皮素的抗氧化能力具有促进作用。

Naringenin is a natural flavonoid possessing good biological activities and therapeutic effects.However,naringenin has poor water solubility and low bioavailability,so it is very important to establish a simple and efficient delivery method for the application of naringenin.In this study,gallocatechin gallate(EGCG)covalently modified zein-hyaluronic acid(HA)composite nanoparticles loaded with naringenin were prepared by an anti-solvent precipitation method.Compared with gallic acid and tannic acid,the zein modified by EGCG had low free amino content and high polyphenol equivalent,and the modification effect was good.The size of the composite nanoparticles,which were formed via electrostatic interaction,hydrogen bonding and hydrophobic interaction,was between 180 and 240 nm,and the smallest particle size(183.62 nm)was obtained when the mass ratio of EGCG modified zein to HA was 10∶1.Due to the covalent modification of zein by EGCG,the encapsulation efficiency and loading capacity of the composite nanoparticles for naringenin were significantly improved,and the encapsulation efficiency was greater than 99%when the mass ratio of naringenin to the EGCG modified zein was 1∶10 or less.Structural characterization showed that most of naringenin was embedded inside the composite nanoparticles,and there were hydrogen bonds and hydrophobic interactions between naringenin,and EGCG or zein.The antioxidant activity of the composite nanoparticles loaded with naringenin was significantly higher than that of free naringenin,indicating that the EGCG modified zein-HA composite nanoparticles loaded with naringenin had an improved effect on the antioxidant activity of naringenin.