Biocompatibility of single-walled carbon nanotube composites for bone regeneration

Abstract

ObjectivesThe 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.MethodsA 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.ResultsNo 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.ConclusionsOur results demonstrate that SWCNT/PLAGA composites exhibited in vivo biocompatibility similar to the Food and Drug Administration approved biocompatible polymer, PLAGA, over a period of 12 weeks. These results showed potential of SWCNT/PLAGA composites for bone regeneration as the low percentage of SWCNT did not elicit a localised or general overt toxicity. Following the 12-week exposure, the material was considered to have an acceptable biocompatibility to warrant further long-term and more invasive in vivo studies.Cite this article: Bone Joint Res 2015;4:70–7

Carbon nanotubes and their polymeric composites: the applications in tissue engineering

“…Results showed that MC3T3-E1 cells adhered, grew/survived and exhibited normal, non-stressed morphology and the addition of SWCNT strengthened cell proliferation rate and gene expression compared to pure PLAGA scaffolds. The authors further investigated the materials in vivo [195] and implanted composite materials into Sprague-Dawley rats for 2, 4,8 and 12 weeks of implantation time. Results showed that no mortality and clinical signs were observed.…”

Effect of different functionalized carbon nanostructures as fillers on the physical properties of biocompatible poly(l-lactic acid) composites

“…Composites of CNSs and biocompatible polymers can combine the properties of the two constituents and act as functional materials for a number of technological applications, [7,8] which include medical devices and implants [9][10][11][12], tissue engineering [13][14][15][16][17][18][19][20][21][22][23][24], drug delivery [25,26], bio-, green and wearable electronics [27][28][29], biosensing [29][30][31][32][33][34], soft robotics [35,36] and smart packaging [37][38][39].…”

Synergic effect of CNT and mechanical loading for acceleration of cell differentiation

“…Besides other applications, an effort has been applied to investigate the potential of carbon nanotubes, CNT, in biological and biomedical applications due to their "onedimensional" structure with high specific surface, stiffness, and electrical properties. Carbon nanotubes have been examined for potential application in bone and neural tissue engineering scaffolds, biosensors, drug and gene delivery as well as cell targeting and imaging [1][2][3][4][5] . Nevertheless, the use of CNT in biomedical applications has to be conducted with caution as pristine CNT was proved to be toxic and may be hazardous to human health.…”

“…Nevertheless, the use of CNT in biomedical applications has to be conducted with caution as pristine CNT was proved to be toxic and may be hazardous to human health. However, the toxicity of CNT can be diminished by functionalization and further covalent modification, which has been investigated in several studies [2][3][4][5] . The length and shape of CNT, presence of catalyst residues, degree of carboxylation, covalent attachment of biomolecules and polymers as well as the dosage of CNT has been shown as important factors for their toxicity and safety [3,4,6] .…”