3.8. In vivo evaluation of wound healing
We also evaluated the in vivo healing ability of mice with aK.pneumoniae -infected wound utilizing the synergetic
antibacterial strategy. Female BALB/c mice withK.pneumoniae -infected wound on their back were used as a model
for the study (Fig. 8A). Fig. 8B displayed representative photographs of
wound healing after different treatments at different time points. And
traces of wound closure for 12 days for all treatment groups were also
drawn (Fig. 8C). We observed that OHH NPs+NIR is almost healed. On day
12, the size of infected wounds after treatment with PBS, HMPB NPs,
ofloxacin,OHH NPs and OHH NPs+NIR reduced to 35.51%, 33.94%, 36.82%,
36.54%, 17.53%, of the original wound area, respectively, indicating
the superiority of combination therapy for infected wound healing (Fig.
8D). Moreover, the insignificant body weight change of mice demonstrated
all treatment groups with the low toxicity (Fig. 8E). In addition, thein vivo antibacterial effect of all treatment groups was also
assessed. As shown in Fig. 8F and 8G, the combination of OHH NPs and PTT
exhibited best antibacterial effect for K.pneumoniae -infected
wound comparing with all single-mode therapies, which was in accord with
the in vitro antibacterial test in Fig. 3. Besides, the
temperature of the wound region treated with OHH NPs increased to
~52 °C after irradiation for 5 min, the temperature of
group PBS did not change significantly. (Fig. S8).