基于磁性荧光双探针基础上的2,4-二氯苯氧乙酸残留的快速免疫检测体系的建立(英文)

建立了一个基于磁性荧光双探针基础上的免疫快速检测体系,以实现液相中快速检测食品中2,4-二氯苯氧乙酸(2,4-D)残留.该体系将2,4-D抗体结合Fe3O4@SiO2-NH2得到的复合物作为磁性探针和固相载体,2,4-D-OVA被标记CdTe@SiO2-NH2作为荧光探针以产生荧光信号,通过荧光探针与磁性探针复合物与2,4-D抗体竞争结合实现免疫快速检测.探讨了荧光探针最佳优化条件,在p H值8.2,2,4-D-OVA加入量为500μL,偶联时间为70 min时,偶联得到的荧光信号最强,双探针检测后得到该检测体系最低检测限为3.55×10-8.得到金磁、量子点荧光双探针免疫系统,绘出标准曲线,得到最低检测限达3.55×10-8.该检测体系与传统ELISA方法相比,可以大大缩短检测时间,放大检测信号.

Establishment of a novel immunoassay system for rapid detection of 2,4-dichlorophenoxyacetic acid residues based on magnetic-fluorescent probes

A novel immunoassay system based on magnetic-fluorescent probes was established to de- tect 2.4-diehlorophenoxyacetic acid （2,4-D） residue in liquid system in food and agricultural prod- ucts. The composites of anti-2,4-D antibody bound to Fe304@ SiO2-NH2 was employed as the solid phase as well as magnetic probe. The composites composed of 2,4-D-OVA labeled with CdTe@ SiO2- NH2 as the fluorescent probe was used to produce fluorescent signal. 2,4-D and its fluorescent probe competed binding the antibody on the surface of the magnetic probe. The optimization of 2,4-D-OVA dosage, coupling PH and reaction time in preparing the fluorescent probe were investigated. It showed that in the synthesis of fluorescent probe 8.2 was the optimal pH, 70 rain was the optimal coupling time ,500 μL amount of 2,4-D-OVA. The standard curve was obtained with the concentration of 2,4- D and the maximum fluorescence intensity. The detection limit of the assay was gotten and it was 3.55 × 10 -8. One reaction step and one washing step were needed. The assay significantly shortened the testing time and amplified the detection signal compared with classic ELISA.