【作者】 王巧芝； 李英；

【Author】 Qiaozhi wang;Ying Li;Key Lab for Colloid and Interface Chemistry of State Education Ministry,Shandong University;

【机构】 山东大学化学与化工学院胶体与界面教育部重点实验室；

【摘要】 近年来,微泡在医学、食品、涂层、以及超声化学等方面的应用使其受到越来越多的关注。在应用过程中,微泡的大小和稳定性均是需要考虑的重要参数,可以通过气体的类型以及壳材料来进行调控。此外,理解气体和壳材料物质特性对微泡稳定性机理的影响也十分必要。本文利用挡板式高强度搅拌的方法产生了稳定的牛血清蛋白空气微泡,以及氮气、氧气、二氧化碳微泡。氮气和氧气微泡具有很好的稳定性,在室温下至少可以稳定存在2 h。二氧化碳微泡稳定性低,但也能够稳定存在一定的时间,这表明牛血清蛋白可以稳定不同气核的微泡。非常有趣的是,通过电子扫描显微镜发现不同气体微泡表面富集的牛血清蛋白可以形成不同的聚集体形貌,说明气体可能诱导了吸附在微泡上牛血清蛋白构象的变化。通过粒径分布、圆二色谱、荧光光谱分析,发现吸附在氮气和氧气微泡上牛血清蛋白的分子尺寸和疏水性较大,而吸附在二氧化碳微泡上的牛血清蛋白疏水性相对较低,表明了微泡内的气体核诱导了吸附在微泡上牛血清蛋白构象的不同转变。通过此研究,我们对蛋白质稳定微泡的机理有了更深入地理解,对于蛋白质微泡在相关领域的应用具有一定的指导意义。更多还原

【Abstract】 In recent years, the applications of microbubbles in medicine, food, coating and sonochemistry has attracted more and more attention. In the application, the size and stability of microbubbles are important parameters to be considered, which can be regulated by the type of gas and shell materials. In addition, it is necessary to understand the effect of gas and properties of shell materials on the stability mechanism of microbubbles. In this paper, the baffled high intensity agitation method was employed to produce not only bovine serum albumin-encapsulated air microbubbles, but also nitrogen, oxygen and carbon dioxide microbubbles. The nitrogen and oxygen microbubbles have good stability, which can be stable for at least 2 hours at room temperature. Though carbon dioxide microbubbles have poor stability, it can also be stable for a certain period of time, which indicates that BSA can stabilize microbubbles with different gas nuclei. It is interesting to found hat bovine serum albumin enriched on the surface of different gas microbubbles can form different aggregates by scanning electron microscopy, which indicates that gas may induce conformational changes of BSA adsorbed on microbubbles. It was found that the molecular size and hydrophobicity of BSA molecules which stabilized nitrogen and oxygen microbubbles were increased by the analysis of particle size distribution, circular dichroism and fluorescence spectrum, while the hydrophobicity of BSA molecules coating carbon dioxide microbubbles was lower. It can be inferred that the gas nuclei in microbubbles induced different conformational changes of BSA molecules adsorbed on microbubbles. Through this study, we can have a deeper understanding on the stability of protein-coated microbubbles containing different gas core, and have a certain guiding significance for the application of protein microbubbles in related fields.更多还原