基于酪蛋白自组装法制备α-生育酚/酪蛋白纳米粒及其α-生育酚稳定性分析

Preparation and Stability of Self-Assembled Casein Nanoparticles Containing α-Tocopherol

采用自组装法使酪蛋白与α-生育酚形成α-生育酚/酪蛋白纳米粒并考察其稳定性。以纳米颗粒的荧光强度为指标,考察在单因素试验条件下α-生育酚与酪蛋白的结合强度。对所制备的复合纳米粒表征后以α-生育酚保留率为指标进行稳定性测试。结果表明制备纳米复合物最佳条件为组装温度37℃、p H 6.8、α-生育酚与酪蛋白质量比1∶300,所得α-生育酚/酪蛋白纳米粒平均粒径为(135.6±13.7)nm,包封率为(97.97±7.38)%,载药量为(0.33±0.03)%。红外光谱表明α-生育酚与酪蛋白存在较强氢键作用。电镜观察纳米粒形态学结构大小均匀,呈较规则球形,且分散性较好。稳定性测试表明复合纳米粒贮存稳定性、热稳定性、冻干稳定性及抗氧化性良好。该方法不仅保护了α-生育酚,而且扩大了产品的应用范围,使其在食品加工中具有理想的应用前景。

α-Tocopherol/casein nanoparticles were prepared by self-assembly and their stability was assessed.The binding strength betweenα-tocopherol and casein was evaluated by fluorescence intensity.The composite nanoparticles were characterized and the retention rate ofα-tocopherol was used as an indicator to evaluate its stability.The results indicated that the optimum conditions for preparingα-tocopherol/casein nanoparticles were as follows:37℃,pH 6.8 andα-tocopherol/casein mass ratio of 1:300.The nanoparticles prepared using the optimized conditions showed an average diameter of(135.6±13.7)nm,an encapsulation efficiency of(97.97±7.38)%and a drug loading of(0.33±0.03)%.Strong hydrogen bonds existed betweenα-tocopherol and casein as indicated by Fourier transform infrared spectroscopy analysis.The nanoparticles were uniform in size and regularly spherical in shape and had good dispersibility.Compared withα-tocopherol,the nanoparticles showed better stability to storage,high temperature,lyophilisation and oxidation.Theα-tocopherol/casein nanoparticles could effectively improve the stability ofα-tocopherol,thereby having a wide scope of application and showing promise in the food industry.