Design and synthesis of a novel PET and ICT based 1,8-naphthalimide FRET bichromophore as a four-input Disabled–Enabled-OR logic gate

•Bichromophoric FRET system based on 1,8-naphthalimide units is synthesized.•1,8-Naphthalimide units are designed as ICT and PET based probes.•System manifests signaling response to protons, hydroxide, Cu2+ and Pb2+ ions.•Disabled–Enabled-OR, INHIBIT and IMPLICATON logic gates are achieved.•Three output combinatorial logic circuit with four chemical inputs is demonstrated.•System can be switched over Disable and Enable mode reversible. The synthesis, sensor activity and logic behavior of a novel donor–acceptor system based on ICT and PET 1,8-naphthalimide fluorescent probes is reported. The system was configured on the “fluorophore1–receptor1–fluorophore2–spacer–receptor2” model where the two probes are integrated in a logic circuit comprising a FRET bichromophoric system with multilevel fluorescent output. The synthesized compound shows colorimetric and fluorescence signaling properties as a function of pH and in the presence of transition metal ions with emphasis on Cu2+ and Pb2+. Due to the remarkable fluorescence and absorption changes in the presence of protons, hydroxide anions, Cu2+ and Pb2+ ions the novel system executes four-input Disabled–Enabled-OR logic gate as well as two-input INHIBIT and IMPLICATON logic gates and is able to act as a three output combinatorial logic circuit with four chemical inputs. Due to the parallel action of four-input input4-Disabled-input3-Enabled-OR logic gate (Output 1) with INHIBIT (Output 2) and IMPLICATON (Output 3) gates, the system can be switched over Disable and Enable mode reversible.