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).