Fig. 4. (A) Fl-loaded hairpin hp1-functionalized UiO-66 NMOFs for the CRET analysis of miRNA-155. The miRNA-155-triggered opening of the hairpin leads, in the presence of K+-ions and hemin, to the self-assembly of the hemin/G-quadruplex that catalyzes the generation of chemiluminescence, λem = 420 nm, and the CRET-induced fluorescence of Fl, λem = 520 nm. (B) CRET-induced fluorescence spectra of Fl, λem = 520 nm, in the presence of variable concentrations of miRNA-155: (a) 0 nM; (b) 5 nM; (c) 20 nM; (d) 50 nM; (e) 100 nM; (f) 200 nM. (C) Derived calibration curve corresponding to the CRET fluorescence signals of Fl generated at variable concentrations of miRNA-155. (D) CRET-induced fluorescence spectra of Rh 6G, λem = 550 nm, in the presence of variable concentrations of miRNA-21, according to Fig. S7:† (a) 0 nM; (b) 20 nM; (c) 50 nM; (d) 100 nM; (e) 333 nM. (E) Derived calibration curve corresponding to the CRET fluorescence signals of Rh 6G generated at variable concentrations of miRNA-21. Error bars derived from N = 3 experiments.
