Fig. 4. Quantifying endogenous H2Sn in a HeLa cell suspension. (a) Fluorescence lifetime change of the τ-probe in negative control cells (H2Sn(–)) incubated with N-ethylmaleimide (NEM) to eliminate H2Sn (left column), native cells (H2Sn-cell) without any treatment (middle column) and positive control cells (H2Sn(+)) incubated with Na2S4 (right column). (b) Fluorescence lifetime change of the τ-probe in native HeLa cells (H2Sn = 65 nM) and cells incubated with 0.065 μM (1×) or 0.13 μM (2×) additional Na2S4. All experiments were repeated at least three times. Error bars represent standard deviation.
