Table 2.

Correlations between MIC values, dye staining, and light scattering signals for the ampicillin-treated E. coli strain.

A
AUC				1 × MIC R2
AFH				0.83
TO-PRO®-3				0.75
Area FSC/SSC				0.65
FSC				0.18
B
Time (h)	AFH R2	TO-PRO®-3 R2	FSC/SSC area R2	FSC R2
1	0.75	0.66	0.51	0.39
2	0.85	0.72	0.66	0.25
3	0.85	0.81	0.68	0.25
4	0.8	0.76	0.54	0.25

To check if the MICs obtained using the standard microdilution assay corresponds to a threshold values impacting the FC measurements, each experiment was described by 2 variables: X_[MIC] and Y_[FC]. X_[MIC] = 1 if the concentration of ampicillin used in the experiment ([Amp]) was ≥ 1 × MIC and X_[MIC] = −1 if [Amp] was < 1 × MIC. Y_[FC] corresponds to the FC data collected for each parameter for each experiment. (A) Y_[FC] corresponds to the areas under the curves (AUCs) of the FC results relative to the time of incubation. (B) Y_[FC] corresponds to the FC values obtained at each hour of incubation. The correlation coefficients (R²) between X_[MIC] and Y_[FC] for each measured parameter (% of cells stained with AFH or TO-PRO®-3, ratios of FSC and the ratios FSC/SSC areas) were calculated for all experiments. Two-tailed P < 0.0001.