三组分抗原的磁分离及分离效率的SERS研究

Magnetic Separation of Tri-component Antigens and SERS-Based Evaluation

利用种子生长法制备了磁性γ-Fe2O3@Au核壳纳米粒子,通过修饰抗体实现表面功能化,利用抗原抗体间的特异性作用,通过外加磁场对三组分抗原进行了逐个以及双抗原的磁分离,采用基于表面增强拉曼光谱(SERS)技术的免疫检测方法对磁分离效率进行了评价,并且研究了该磁分离和效率评估方法的极限工作浓度.研究结果表明,该磁免疫分离法能对三组分混合抗原中的任意组分进行很好的选择性分离,而不影响其它抗原的存在,使其分离后溶液中被分离抗原的浓度降低到SERS免疫检测限,分离所能达到的极限抗体浓度约0.1pg/mL.

Magnetic γ-Fe2O3@Au core/shell nanoparticles were prepared by the growth of Au shell onto the seeds of γ-Fe2O3 nanoparticles.The γ-Fe2O3@Au nanoparticles were functionalized by the modification of antibody.By the specific interaction between antigen and antibody,one of the antigens was separated in order or two antigens were separated together with the assistance of external magnetic field.The efficiency of magnetic separation was evaluated based on surface enhanced Raman spectroscopy （SERS） immunoassay technique.The concentration limitation for the magnetic separation and the SERS evaluation were obtained.The results showed that the method of magnetic immune separation has been achieved to separate any components in the media with three antigens without any influence on the existence of other antigens.The concentration of the separated antigen was reduced to the detection limitation of SERS-based immunoassay which could reach about 0.1 pg/mL.