MOF-Based G−Quadruplex/Hemin DNAzymes for Cascade Reaction

DNA-based biomimetic enzymes have attracted extensive attention due to their unique structure and stability compared to natural enzymes. Meanwhile, the specific sequences of DNA itself also have a catalytic effect. Herein, we first designed three guanine-rich DNA sequences numbered c−Myc3c, PG4TC, and TTT to construct g−quadruplex/hemin DNAzymes. Then, the g−quadruplex/hemin DNAzymes with the best activity were selected by a comprehensive examination of activity, degradation rate, and affinity. Subsequently, the stability and reusability of UiO66−DNAzymes were investigated using UiO66 as the carrier to immobilize DNAzymes. The results showed that UiO66−DNAzymes had excellent reusability and stability. Finally, UiO66−DNAzymes were successfully used for glucose detection by cascading with glucose oxidase (GOx) with a detection limit of 0.62 μM. The constructed glucose sensor had a good specificity, which is of great significance for developing a novel, accurate, fast, and economical glucose detection sensor.Keywords:metal-organic frameworks;DNAzymes;enzyme immobilization;biomimetic enzymes;glucose detection