Fig. 1. (A) Photoluminescence (PL) spectra of Cou, TPETP-N3 and Cou–DEVD–TPETP (10 μM) in DMSO/PBS buffer (v/v = 1/99). (B) PL spectra of Cou–DEVD–TPETP (10 μM) upon incubation with different concentrations of caspase-3 (λex: 405 nm, emission collected from 430–550 nm is from Cou–DEVD and that at 600–780 nm is from the TPETP residue).
