Aptamer-binding zirconium-based metal-organic framework composites prepared by two conjunction approaches with enhanced bio-sensing for detecting isocarbophos.

A novel label-free and enzyme-free detection strategy has been developed for the electrochemical biosensor detection of isocarbophos (ICP) using UiO-66-NH2 and aptamer as the signal transducers. In this work, the ICP aptamers were attached to UiO-66-NH2 through physical mixing and chemical combination methods. In the presence of ICP, the aptamers could undergo conformational change and bind to them, which prevent the electron transfer to the surface of electrode. By comparing the two conjunction approaches of aptasensors, these proposed strategies could selectively and sensitively detect ICP with a detection limit of 6 ng mL-1 (20.74 nM) and 0.9 ng mL-1 (3.11 nM). Furthermore, we have also demonstrated the capability of this strategy in the detection of ICP in real samples from vegetable and fruit extract, indicating the potential application of this strategy in food safety issues.