Objectives. The purpose of this study was to evaluate in vivo biocompatibility
of novel single-walled carbon nanotubes (SWCNT)/poly(lactic-co-glycolic
acid) (PLAGA) composites for applications in bone and tissue regeneration. Methods. A total of 60 Sprague-Dawley rats (125 g to 149 g) were implanted
subcutaneously with SWCNT/PLAGA composites (10 mg SWCNT and 1gm
PLAGA 12 mm diameter two-dimensional disks), and at two, four, eight
and 12 weeks post-implantation were compared with control (Sham)
and PLAGA (five rats per group/point in time). Rats were observed
for signs of morbidity, overt toxicity, weight gain and food consumption,
while haematology, urinalysis and histopathology were completed
when the animals were killed. Results. No mortality and clinical signs were observed. All groups showed
consistent weight gain, and the rate of gain for each group was
similar. All groups exhibited a similar pattern for food consumption.
No difference in urinalysis, haematology, and absolute and relative
organ weight was observed. A mild to moderate increase in the summary toxicity
(sumtox) score was observed for PLAGA and SWCNT/PLAGA implanted
animals, whereas the control animals did not show any response.
Both PLAGA and SWCNT/PLAGA showed a significantly higher sumtox
score compared with the control group at all time intervals. However,
there was no significant difference between PLAGA and SWCNT/PLAGA
groups. Conclusions. Our results demonstrate that SWCNT/PLAGA composites exhibited in
vivo biocompatibility similar to the Food and Drug Administration
approved biocompatible