2.7. Bacterial Kinetic Study. A 0.05 mL aliquot of an E. coli
suspension was added to 5.00 mL of LB, followed by the addition of
different samples. The final concentrations of the samples were 0.040
mg/mL pure HSSNs and 0.005, 0.020, and 0.100 mg/mL polymyxin
B-doped HSSNs. H2O and pure HSSNs were used as controls. The
initial time of adding each sample to a LB bacterial suspension was
recorded as zero. The suspension was incubated at 37 °C at a shaking
speed of 200 rpm. At each set time interval, a 0.20 mL aliquot of the
suspension was withdrawn from the incubator and placed in a cuvette
containing 1.80 mL of LB broth. Then, an OD measurement at a
wavelength of 600 nm was performed to estimate the amount of
bacteria present in the samples.