Simulation results spin-labelled liposomes tau_c rotational correlation time S_zz segmental order parameter tau_f fluorescence lifetime g_iso isotropic g-value a_iso apparent isotropic hyperfine coupling eta viscosity Fit data sets (linear fits in Figure S6) mean Std. Dev. Probe Parameter Intercept Slope Intercept Slope 5-DSPC tau_c -0.578 0.622 0.078 0.045 S_zz -0.356 0.074 0.007 0.004 12-DSPC tau_c -0.793 0.675 0.122 0.070 S_zz -0.676 0.094 0.006 0.003 16-DSPC tau_c -1.235 0.740 0.085 0.049 S_zz -1.229 0.262 0.012 0.007 C10-BODIPY tau_f -0.719 0.446 0.024 0.010 Results from EPR simulations 16-DSPC g_iso a_iso in MHz tau_c in ns S_zz mean eta-values in mPas from tau_c from S_zz average Liposome No ROS 2.0061 40.01 2.13 0.211 129.6 128.6 129.1 Hydrogen Peroxide 2.0060 40.17 1.99 0.208 118.1 122.7 120.4 Hydroxyl Radical 2.0060 40.07 1.99 0.208 118.2 122.5 120.4 PLs No ROS 2.0061 39.93 2.09 0.208 126.3 122.5 124.4 Superoxide Radical 2.0060 40.03 2.07 0.208 124.7 122.5 123.6 Hydrogen Peroxide 2.0060 40.10 2.02 0.208 120.7 122.5 121.6 Hydroxyl Radical 2.0060 40.10 2.02 0.208 120.7 122.5 121.6 12-DSPC g_iso a_iso in MHz tau_c in ns S_zz mean eta-values in mPas from tau_c from S_zz average Liposome No ROS 2.0060 40.33 4.72 0.341 149.0 166.3 157.6 Hydrogen Peroxide 2.0059 40.50 4.65 0.339 145.8 156.2 151.0 Hydroxyl Radical 2.0059 40.40 4.39 0.339 133.8 156.2 145.0 PLs No ROS 2.0061 40.17 4.78 0.341 151.8 166.3 159.0 Superoxide Radical 2.0060 40.40 4.78 0.341 151.8 166.3 159.0 Hydrogen Peroxide 2.0060 40.40 4.39 0.339 133.8 156.2 145.0 Hydroxyl Radical 2.0060 40.33 4.39 0.339 133.8 156.2 145.0 5-DSPC g_iso a_iso in MHz tau_c in ns S_zz mean eta-values in mPa from tau_c from S_zz average Liposome No ROS 2.0060 41.33 6.74 0.652 182.6 191.2 186.9 Hydrogen Peroxide 2.0059 41.33 6.51 0.652 172.5 191.2 181.9 Hydroxyl Radical 2.0059 41.33 6.51 0.652 172.5 191.2 181.9 PLs No ROS 2.0060 41.17 6.85 0.652 187.4 191.2 189.3 Superoxide Radical 2.0059 41.37 6.85 0.652 187.4 191.2 189.3 Hydrogen Peroxide 2.0059 41.37 6.49 0.650 171.8 183.5 177.7 Hydroxyl Radical 2.0059 41.37 6.49 0.650 171.8 183.5 177.7 Results from TCSPC simulations tau_f in ns eta in mPas Liposomes mean SD No ROS 1.83 158.7 10.5 Hydrogen peroxide (low) 1.80 152.9 10.0 Hydroxyl radical (low) 1.78 149.1 10.9 Hydrogen peroxide (high) 1.81 154.8 10.1 Hydroxyl radical (high) 1.80 152.9 10.2 PLs No ROS 1.84 160.6 10.5 Superoxide radical 1.79 151.0 10.1 Hydrogen peroxide 1.78 149.1 10.0 Hydroxyl radical 1.81 154.8 10.8