不同修饰基团的副溶血性弧菌适配体在磁性纳米颗粒表面的固定效果和反应活性研究

目的 研究副溶血性弧菌适配体的不同修饰基团对磁性纳米颗粒修饰效果和与副溶血性弧菌结合活性的影响。方法 采用一步合成法合成氨基修饰的磁性纳米颗粒, 将其分别与氨基、生物素和羧基修饰的副溶血性弧菌适配体结合, 通过紫外吸收间接分析适配体的固定率, 并利用外加磁场分离目标物, 平板涂布确定磁分离效果。结果 生物素修饰的副溶血性弧菌适配体与磁性纳米颗粒有更高的结合效率, 为62.16%。在菌液浓度较低时, 不同基团修饰的适配体与磁性纳米颗粒结合后对副溶血性弧菌的分离效果影响较小, 但当菌液浓度为105 CFU/mL时, 不同基团修饰对副溶血性弧菌分离效果差距明显, 氨基修饰的适配体显示了更为优异的反应活性, 分离率为69.24%, 分别较生物素和羧基修饰的适配体高21.04%和16.26%。结论 氨基修饰的副溶血性弧菌适配体在磁性纳米颗粒表面固定后显示了更为优越的反应活性, 为副溶血性弧菌分离和检测的相关应用研究提供参考。

Study of immobilization effects and reactivities of Vibrio parahaemolyticus aptamers with different modified groups on the surface of magnetic nanoparticles

Objective To study the different modification groups of Vibrio parahaemolyticus aptamers on the modification effects of magnetic nanoparticles and their binding activities with Vibrio parahaemolyticus. Methods The amino-functionlized magnetic nanoparticles were synthesized by one-step synthesis method and then combined with amino, biotin and carboxyl modified Vibrio parahaemolyticusaptamers respectively. The fixed rate of aptamer was detected indirectly by ultraviolet absorption and the magnetic separation effect was determined by plate coating after the target was separated by external magnetic field. Results The biotin modified Vibrio parahaemolyticus aptamer had a higher binding efficiency with magnetic nanoparticles, which was 62.16%. At the low concentration of bacterial solution, the aptamers modified with different groups had less effect on the isolation of Vibrio parahaemolyticus when combined with magnetic nanoparticles. However, when the concentration of bacterial solution was 105 CFU/mL, the combination of different group modified Vibrio parahaemolyticus aptamers with magnetic nanoparticles had significant difference on the separation of Vibrio parahaemolyticus. The amino modified aptamer of Vibrio parahaemolyticus showed more excellent reaction activity after fixed on magnetic nanoparticles, with a separation rate of 69.24%, 21.04% and 16.26% higher than biotin and carboxyl modified aptamers, respectively. Conclusion The results show that the amino-Vibrio parahaemolyticus aptamer shows better activity with Vibrio parahaemolyticus after immobilized on the surface of magnetic nanoparticles. This study provides a reference for the future study of applications of Vibrio parahaemolyticus aptamer and magnetic nanoparticle in Vibrio parahaemolyticus separation and detection.