Figure 9. Antibacterial efficacy of the hydrogel delivery system tested using Streptococcus pneumoniae and NTHi. The 100µM[AgNPs-PVP]-18%[P407] formulation (500 µL) was stored at 37°C until it became a solid-like gel; prewarmed bacterial broth (500 µL) was subsequently added to the hydrogel. The tube was then incubated at 37°C for 24 hours, by the end of which, 100 µL of the culture was applied on agar plates and incubated for 24 hours. The hydrogel formulation, 100µM[AgNPs-PVP]-18%[P407] completely eradicated both S. pneumoniae and NTHi.