Potentiometric Cu2+-selective electrode with subnanomolar detection limit

► To the best of our knowledge, this ionophore and modified separate solution method has not previously been used in the development of a Cu2+-selective electrode. ► This sensor has Wider linear range and subnanomolar detection limit. ► This electrode has faster response time and better selectivity. ► This electrode has faster response time and better selectivity. ► Proposed electrode has acceptable performance in analysis of real samples.