Comparison of NaCl-P buffer and Ringer solution in viability determination of P. aeruginosa by flow cytometry. (A) Relative frequencies of PI stained cells (5 μg/mL) for stationary grown P. aeruginosa from pure culture in NaCl-P buffer and Ringer solution at different dye incubation times. (B) Relative frequencies of PI stained cells in exponential and stationary growth phases from pure culture prepared in Ringer solution without GTA and with 0.05 mg/mL GTA. Relative frequency of PI stained cells was determined by ratio of relative frequency of PI stained events in untreated and isopropanol-treated samples. Error bars represent standard deviation of three biological replicates; # indicates a statistically significant difference (p < 0.05, paired Student t-test).