A sensitive and rapid method for the detection of Vibrio alginolyticus is always in high demand. In this research, a magnetic relaxation switch sensor for the rapid detection of Vibrio alginolyticus has been successfully developed based on the aptamer-functionalized magnetic nanoparticle. The optimal concentration of aptamer for cross-linking was 6 μM, and the coupling time was 7 h. The optimal detection conditions were as follows: the concentration of Fe₃O₄@SiO₂-Apt_VA was 0.06 mg/mL, the incubation time was 10 min and the detection could be completed within 15 min. Meanwhile, the dependence of bacteria concentration on different relaxation characteristic signals was compared, and it was clear that ΔT_2w exhibited better correlationship. In addition, the maximum NaCl limit for nanoparticles to remain stable is 0.4% (w/w). Under the optimal conditions, the LOD of this method based on ΔT_2w is 26 CFU/mL and the recovery is 91.30–113.09%. Good specificity was proved. This method provides new choice for the rapid detection of Vibrio alginolyticus.

一种用于检测溶藻弧菌的灵敏而快速的方法一直是急需的。在这项研究中，基于适体功能化的磁性纳米颗粒，成功开发了一种用于快速检测溶藻弧菌的磁弛豫开关传感器。交联适体的最佳浓度为6 μM，偶联时间为7 h。最佳检测条件为：Fe ₃ O ₄ @SiO ₂ -Apt _VA的浓度为 0.06 mg/mL，孵育时间为 10 分钟，检测可在 15 分钟内完成。同时，比较了细菌浓度对不同弛豫特征信号的依赖性，很明显ΔT _2w表现出更好的相关性。此外，纳米粒子保持稳定的最大 NaCl 限值为 0.4% (w/w)。在最佳条件下，该方法基于ΔT _2w的 LOD为 26 CFU/mL，回收率为 91.30–113.09%。证明了良好的特异性。该方法为溶藻弧菌的快速检测提供了新的选择。