Are carbon nanotubes (CNTs) based nanocomposites the future of biomedical applications?

Authors: Muthusamy Saranya

In the recent decade, there has been several publications that have analysed CNTs based nanocomposites for tissue engineering. CNTs exhibit remarkable physical (high surface area and aspect ratio), chemical (mimics protein structures, encourages adhesion) and high mechanical integrity. Due to these properties, CNTs encourage expansion of several cells like myoblast, neurons and osteoblasts and have attracted the attention of scientific community.

Khan et al. published an interesting study on functionalized multiwall-CNT (f-MWCNT) and hydroxyapatite nanorods (n-HA) reinforced with polyproplene (PP) for osteoblast proliferation in Scientific Reports in early 2021. Earlier to this, there has been no report on PP/n-HA/f-MWCNT based nanocomposite and study on its properties as well as biocompatibility behaviour. PP is polyolefin widely considered for various biomedical applications like bone cement, bone plates and for pelvic floor repair due to high dimensional stability, shape and chemical resistance and its ability to be autoclaved. In this study, different concentration of f-MWCNT (0.1-0.3 wt.%) and n-HA (15-20 wt.%) when put in PP to form a hybrid nanocomposite enhancing the mechanical properties, biocompatibility, and dimensional strength of PP. In fact, the importance of f-MWCNT in achieving clearance and removal from body compared to the un-modified MWCNT was also mentioned in the study.  

This study has demonstrated possibility to achieve material homogeneity and maintaining the appropriate mechanical and biocompatibility properties of individual fillers (f-MWCNT and HA) within the hybrid nanocomposite. The study reveals biocompatibility between cells and the hybrid nanocomposite with PP /20 wt.% n-HA / 0.2 wt.% f-MWCNT showing no negative influence on viability and osteoblast proliferation but a relative increase of them making it a suitable sample for light loaded bone implants.  In line with the scope of this study, the RESTORE consortium beneficiary UOULU is leading a task to integrate f-MWCNT into rigid 3D matrices and investigate the effects of external physical stimulations. Within RESTORE, we expect to provide an effective approach to manage the specific unmet clinical needs to treat knee chondral lesions.

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