【摘要】 基于金属有机骨架材料(Uio-66-NH2)的荧光猝灭特性以及对核酸适配体的吸附性,结合核酸适配体的高亲和力与高特异性识别能力,构建了针对沙门氏菌检测的荧光生物传感器,当有荧光素修饰的沙门氏菌、适配体被材料吸附到表面时,由于材料诱导电子转移猝灭了荧光素的荧光,若溶液中存在沙门氏菌,则沙门氏菌与其适配体特异性结合后从材料表面脱附,材料与荧光素之间的电子转移过程被切断,荧光素的荧光恢复。基于此原理构建的荧光传感器的信号与沙门氏菌浓度的对数在101~105cfu/m L范围内呈良好的线性关系,检出限(S/N=3)为7 cfu/m L,将该方法用于虾肉样品中沙门氏菌的检测,加标回收率为90.0%~108.0%,该传感器对沙门氏菌有较好的选择性与灵敏度。更多还原

【Abstract】 A fluorescence biosensor to detect salmonellae was established based on metal organic frameworks(MOFs) and aptamer. Uio-66-NH2 material has a strong adsorption capacity for FAMlabelled aptamers and could completely quench the fluorescence of FAM. The aptamer of nucleic acid has high affinity and high specificity. In the presence of salmonellae,the binding between the FAMlabelled aptamer and salmonellae will alter the conformation of FAM-labelled aptamer. Therefore,the interaction between the FAM-labelled aptamer and MOFs would be disturbed. Such interactions will cause the releasing of the FAM-labelled aptamer from the Uio-66-NH2 material,resulting in the restoration of FAM fluorescence. And this method was applied to the estimation of salmonellae in shrimp samples,with the recoveries of 90. 0%-108. 0%. The fluorescence intensity of the system has a linear relationship with the logarithm of salmonellae concentration in the range of 101-105 cfu/m L,with a detection limit(S/N = 3) of 7 cfu/m L. The experimental results showed that the biosensors had a high sensitivity and a high selectivity to salmonellae.更多还原