Fig. 3: Time-gated detection enables accurate recovery of total intensity and CPL spectra of long-lifetime lanthanide emission from ~18 µM Λ-Eu·L¹ in a 50:50 solution of MeCN and MeOH Eu·L¹ (τ ~ 800 µs) in the presence of short-lifetime non-polarised fluorescence emission of ~350 µM Rh6G (τ ~ 4 ns).

a The total emission measured by both constant and time gated modes is equivalent when there is no background fluorescence. b CPL of Λ-Eu·L¹ is recovered by both constant and time-gated modes is equivalent when there is no background fluorescence. c Time-gating removes non-polarised fluorescent background from measurements of total intensity. d CPL is correctly recovered by both constant and time-gated modes in the presence of non-circularly polarised background fluorescence. Samples excited at 365 nm and spectra were recorded with standard scan settings. Note that the concentration of Λ-Eu·L¹ is slightly decreased from a, b to c, d due to dilution.