明胶及酪蛋白作为封闭剂及保存稳定剂在免疫磁球制备中的应用

Application of gelatin and casein as blocking agent and stabilizer in preparation of immunomagnetic beads

目的研究免疫磁球封闭剂及保存稳定液的性能,以保证微生物捕获效果。方法以沙门氏菌为目标捕获物,通过制备抗沙门氏菌免疫磁球,将明胶和酪蛋白作为封闭液及保存液成分,对免疫磁球特异性捕获及免疫磁球的保存周期进行了研究。结果 7.5%明胶溶液作为免疫磁球的封闭液时,免疫磁球非特异性吸附低于5%,1%酪蛋白的结果高于10%;保存液中添加1‰酪蛋白和1‰明胶,在37℃条件下放置3 d后,免疫磁球的特异性捕获率在70%以上。结论明胶作为封闭剂可以降低免疫磁球的非特异性吸附,1‰明胶与1‰酪蛋白在保存液中共同作用有助于免疫磁球抗体活性的保存。

ABSTRACT:Objective To research the performance of the blocking agent and storage stable liquid of immunomagnetic beads, and to guarantee the capture efficiency of microorganism.MethodsThe gelatin and casein were used as blocking agent and preservation solution in the preparation of anti-Salmonella immunomagnetic beads. The specific capture rate and shelf life of the immunomagnetic beads were obtained and examined.ResultsThe non-specific binding rate ofEscherichia coli was less than 5% after blocking the immunomagnetic beads with 7.5% of gelatin, the specific binding rate maintained above 70% after 3 d at 37℃ when the beads were preserved in 1 ‰ of casein and 1 ‰ of gelatin..ConclusionAs ablocking agent, gelatin could reduce the non-specific binding of immunomagnetic beads, and 1 ‰ of gelatin with 1 ‰ of casein in the preservation solution exhibited a conducive ability to keep the activity of antibody on immunomagnetic beads.