Fig. 3. Pseudocolored ratiometric TPM images of HepG2 cells incubated with (a) SE1 (2 μM) and (d) 1 (2 μM). HepG2 cells were pretreated with (b) bis(4-nitrophenyl) phosphate (BNPP, 500 μM) and (c) 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF, 2 mM) for 30 min before labeling with SE1. (e) Average Fyellow/Fblue intensity ratios in the TPM images. Images were acquired using 740 nm excitation and emission windows of 420–470 nm (blue) and 520–570 nm (yellow). Scale bars = (a and b) 16, and (c and d) 19 μm.
