乳清蛋白-海藻酸二醛微胶囊的制备及控释特性

Fabrication and controlled release characteristics of whey protein-alginate dialdehyde microcapsule

【目的】以乳清蛋白(WPI)和海藻酸二醛(ADA)为原料制备WPI-ADA共聚物微胶囊,研究WPI和ADA之间的相互作用及对微胶囊中姜黄素控释效果的影响,为开发姜黄素的包埋体系提供理论依据。【方法】采用湿热法制备WPIADA共聚物,利用接枝度、褐变程度和红外光谱分析探究WPI和ADA之间的相互作用,研究不同比例共聚物对乳液粒径、电位、流变性、X射线衍射、热重分析等理化特性的影响,以及共聚物对微胶囊中姜黄素的释放特性的影响。【结果】制备微胶囊最佳的WPI和ADA质量比为1∶3。接枝度、褐变强度和傅里叶红外光谱分析证实了共轭物的形成。在共价结合作用的驱动下,WPI-ADA乳液粒径从415.4 nm减小到325.9 nm,微胶囊包埋率从83.9%增加到95.4%。此外,WPI-ADA共聚物微胶囊表现出较好的热稳定性。体外模拟消化实验结果表明,WPI-ADA共聚物微胶囊对姜黄素表现出缓释行为,且在模拟胃液和模拟肠液中达到最大释放量的时间由12 h延长至24 h。【结论】在共价相互作用下,WPI-ADA共聚物能够改善微胶囊的理化性质和姜黄素的释放特性,可用于修饰微胶囊体系和疏水性活性物质的递送。

[Objective]This study used whey protein(WPI)and alginate dialdehyde(ADA)to prepare WPIADA copolymer microcapsules,and the interactions between WPI and ADA and their effects on the controlled release of curcumin in the microcapsules were investigated to provide a theoretical basis for the development of the encapsulation system of curcumin.[Method]WPI-ADA copolymers were prepared using a wet-heat method,and the interaction between WPI and ADA was explored through analysis of grafting degree,browning intensity,and infrared spectroscopy.The effects of different proportions of copolymers on the emulsion were studied in terms of particle size,zeta potential,and rheological properties.The influence of copolymers on microcapsules was investigated using X-ray diffraction,thermogravimetric analysis,and the release characteristics of curcumin.[Result]The results indicated that the optimum mass ratio of WPI and ADA for preparing microcapsules was 1∶3.Grafting degree,browning intensity and Fourier transform infrared spectroscopy(FTIR)analyses confirmed the formation of conjugates.Driven by covalent binding,the particle size of WPI-ADA emulsion decreased from 415.4 nm to 325.9 nm,and the microcapsule encapsulation efficiency increased from 83.9%to 95.4%.Additionally,WPI-ADA copolymer microcapsules exhibited good thermal stability.In vitro simulated digestion experiments demonstrated that WPI-ADA copolymer microcapsules exhibited certain controlled release capabilities,extending the time for maximum curcumin release from 12 hours to 24 hours in simulated gastric fluid and intestinal fluid.[Conclusion]Under covalent interaction,WPI-ADA copolymers can improve the physicochemical properties and curcumin release properties of microcapsules,and can be used to modify the microcapsule system and the delivery of hydrophobic active substances.