本研究尝试了一种新型的基于KMnF3纳米探针的NMR方法对沙门氏菌进行快速检测。通过将沙门氏菌单抗与羧基磁珠偶联制备免疫磁珠，并以此为NMR分子探针，以免疫磁珠为生物传感器，特异性地捕获并检测出样品中的致病菌，从而建立一种更快的检测沙门氏菌的方法。实验发现，活化剂的添加量，捕获沙门氏菌的缓冲液，细菌培养时间和探针添加量在不同程度上影响着检测样品的弛豫时间。通过实验对捕获条件进行优化，得出的最佳捕获条件是：一份的KMnF3，活化时加入是KMnF3质量五倍的EDC·HCL、NHS；用灭菌的蒸馏水作为捕获沙门氏菌的缓冲液；加入80 μL的抗体-KMnF3捕获培养10 h的沙门氏菌。本研究为沙门氏菌的检测提供了新的方法和途径，缩短了检测时间，为低磁场核磁共振技术在食品安全领域开辟新的空间。

This work attempted to establish a new method for the rapid detection of Salmonella spp., using a nuclear magnetic resonance (NMR) method based on potassium manganese trifluoride (KMnF3) nanoprobes. Immunomagnetic beads were produced by coupling an anti-Salmonella monoclonal antibody with carboxyl magnetic beads, which were used as NMR molecular probes and biological sensors to specifically capture and detect the pathogenic bacteria in samples, in order to create a more rapid method to detect Salmonella spp. The results showed that the relaxation time in sample detection was influenced to various degrees by the amount of added activator, the choice of buffer solution for the capture of Salmonella spp., the bacterial incubation time, and the volume of added NMR probes. The capturing conditions were optimized as follows: the mass ratio of potassium manganese trifluoride to 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride- and N-hydroxysulfosuccinimide-modified magnetic beads at activation was 1:5; 80 μL of antibody-potassium manganese trifluoride was required to specifically capture Salmonella spp. incubated for 10 h; sterile distilled water was used as the buffer. A new method and approach for the detection of Salmonella spp. was provided in this study, and the method shortened the detection time and expanded the application of low-field nuclear magnetic resonance in the field of food safety.

江西省科技计划项目（20151BBG70049）