六种蛋白质与生物纳米磁珠的吸附性能研究

近年来,纳米磁珠在生物技术和生物医学领域受到了广泛的关注,但蛋白质与生物纳米磁珠之间往往存在非特异性吸附,故从蛋白质角度出发,研究不同蛋白质的结构及理化性质与磁珠吸附的关系。利用两种生物纳米磁珠,对6种不同蛋白质与磁珠的吸附特异性展开研究。使用蛋白质分析软件分析各个蛋白结构及蛋白质性质与磁珠吸附特异性的关系。不同的蛋白质与纳米磁珠之间存在非特异性吸附,蛋白大小与磁珠吸附蛋白的能力没有明显关联性。随着蛋白β折叠比例的降低,蛋白质与磁珠的非特异性吸附降低。β折叠比例最大的蛋白——人肿瘤坏死因子-α(TNFα)与磁珠的非特异性吸附最多,可通过吸附获得单一蛋白条带。β折叠比例最小的人膜联蛋白A5(Annexin A5)与磁珠的非特异性吸附最少。当Annexin A5融合增强绿色荧光蛋白(EGFP)后,β折叠比例升高,与磁珠的非特异性吸附增加。不同蛋白质的大小与磁珠的非特异性吸附无明显的相关性,磁珠对蛋白的非特异性吸附能力与蛋白结构的β折叠比例呈正相关,蛋白质的二级结构是影响蛋白质与磁珠非特异性吸附的重要因素。

The Study on the Adsorption Properties of Six Proteins on Biological Magnetic Nanobeads

In recent years,magnetic nanobeads have received extensive attentions in the fields of biotechnology and biomedicine;however,there is often non-specific adsorption between proteins and biological magnetic nanobeads.Therefore,the relationship between the structure and physicochemical properties of proteins and magnetic bead adsorption was studied from the perspective of proteins.Using two types of biological magnetic nanobeads,the adsorption specificities of 6 different proteins on the surfaces of magnetic beads were studied.Each protein’s structure was analyzed by protein analysis software,and the structure and physicochemical property of different proteins were obtained.The relationship between protein properties and the adsorption specificity of the magnetic bead was analyzed.There was non-specific adsorption for different proteins on the surfaces of magnetic nanobeads,and the size of the protein was not significantly related to the ability of magnetic beads to adsorb proteins.As theβ-sheet ratio of protein decreased,the non-specific adsorption of protein on the surfaces of magnetic beads also decreased.Human Tumor Necrosis Factor alpha(TNFα)with the largestβ-sheet ratio had the most non-specific adsorption on the magnetic beads,and a single protein band was obtained by the adsorption.Human Annexin A5 with the smallestβ-sheet ratio had the least nonspecific adsorption on the magnetic beads.After Annexin A5 was fused with Enhanced Green Fluorescent Protein(EGFP),theβ-sheet ratio was increased,and the non-specific adsorption by magnetic beads also increased.In conclusion,there is no obvious correlation between the protein size and the non-specific adsorption on the surfaces of magnetic beads.The non-specific adsorption capacity of magnetic beads to proteins is positively related to theβ-sheet ratio of the protein structure.Protein secondary structure is an important factor for the non-specific adsorption of proteins to magnetic beads.