Fig. 4: Enzyme-coupled FARMA method.

a Schematic operational principle and representative enzymatic reactions. b Time-resolved emission of liposome-encapsulated FAR-1 with the membrane-impermeable substrate 2-naphthyl phosphate and the enzyme alkaline phosphatase (ALKP, 16 µg ml−1). Experiments were conducted with POPC : POPS (8 : 1) liposomes at 22 °C. c Time-resolved emission of liposome-encapsulated FAR-1 and the slowly permeating substrate phenyl-β-d-galactopyranoside, with and without the enzyme β-galactosidase (β-gal, 43 µg ml−1). Experiments were conducted with POPC : POPS (8 : 1) liposomes at 22 °C.