Antibacterial Efficacy of the AgNPs-PVP-Containing Hydrogel
Using the formulation containing the highest concentration of AgNPs-PVP
while still maintaining reverse thermal gelation, i.e.,
100µM[AgNPs-PVP]-18%[P407], antimicrobial efficacy was
examined. As discussed previously, S. pneumoniae and NTHi, the
two main pathogens causing OM4,5, were used.
To mimic the environment of an auditory bullae during an active episode
of OM, which has the volume of 1.52 ± 0.26 mL (mean ± SD)71, 500 µL hydrogel formulation was applied to 500 µL
bacteria broth and incubated for 24 hours. The antibacterial activity of
hydrogel formulations was assessed by counting the colony-forming unites
(CFU) at the end of the 24-hour incubation (Figure 9). While
countless
colonies of S. pneumoniae and NTHi were observed on the agars
that were untreated or treated with 18%[P407],
100µM[AgNPs-PVP]-18%[P407] achieved complete eradication of
both pathogens, demonstrating the potential of this local treatment to
cure OM with high bacterial counts.