Study of the detection of bisphenol A based on a nano-sized metal–organic framework crystal and an aptamer†
Abstract
Based on the adsorption ability of a nano-sized iron metal–organic framework (Fe-MIL-88B–NH2) to a DNA aptamer, a fluorescent biosensor for BPA was developed. In this system, the aptamer was modified with a fluorescent dye as a fluorescent DNA probe. With the introduction of an Fe-MIL-88B–NH2 aqueous solution, the aptamer probe can be adsorbed by Fe-MIL-88B–NH2, and then the fluorescence of the dye will be quenched by Fe-MIL-88B–NH2. When the fluorescent DNA probes were mixed with a sample solution containing the target BPA, a recognition process driven by BPA happened, which prevented the adsorption of the fluorescent DNA probe on Fe-MIL-88B–NH2, and made the fluorescent DNA probe freely exist in the solution. This results in the retention of the fluorescence of the solution. The limit of the proposed detection method was 4.1 × 10−14 mol L−1, with a linear working range from 5.0 × 10−14 to 2.0 × 10−9 mol L−1, and good selectivity.