Table 5.
CNT composites | Type | Medical application | Species | Major conclusions | Reference |
---|---|---|---|---|---|
Functionalized | |||||
Heteroatoms (N, F, P/B) | MWCNT | Wound healing |
K. pneumoniae P. aeruginosa E. coli B. subtilis |
f-MWCNT showed 82.53%, 80.98%, 76.83%, and 77.41% biofilm inhibition against B. subtilis, E. coli, K. pneumoniae, and P. aeruginosa, respectively | (Murugesan et al., 2020) |
Compounds displaying antimicrobial activity: | |||||
Surfactants | |||||
Sodium cholate | SWCNT | Antimicrobial agents |
E. coli S. enterica |
Antibacterial effect increased with increasing SWCNT concentration as demonstrated by the optical density reduction from 0.8 to 0.4 | (Dong et al., 2012) |
Photosensitizers | |||||
Rose Bengal (RB) (APT) |
MWCNT | Antimicrobial agents | E. coli | RB-CNT-mediated photodestruction resulted in 5.46 log reduction for E. coli | (Anju et al., 2018) |
Malachite green (MG) (APT) |
MWCNT | Medical devices |
P. aeruginosa S. aureus |
Upon MG-c-MWCNT treatment, S. aureus and P. aeruginosa viability was reduced by 5.16 and 5.55 log, respectively | (Anju et al., 2019a) |
Methylene blue (MB) (APT) |
MWCNT | Medical devices |
E. coli S. aureus |
Photodynamic activation of MB-c-MWCNT resulted in 4.86 and 5.55 log reductions in E. coli and S. aureus viability, respectively | (Parasuraman et al., 2019) |
Toluidine blue (TB) (APT) |
MWCNT | Medical devices |
P. aeruginosa S. aureus |
P. aeruginosa and S. aureus planktonic cells treated with TB-c-MWCNT and exposed to light irradiation reduced their viability by 4.91 and 5.47 log, respectively | (Anju et al., 2019b) |
Antimicrobial peptides | |||||
AMPs: TP359, TP226, and TP557 | SWCNT | Antimicrobial agents | S. aureus | Non-treated 3D skin showed 4 log CFU/g increase in 2 h after incubation with bacteria, whereas the f-SWCNT-s-Ag-treated skin showed only 1 log CFU/g increase in bacterial counts | (Chaudhari et al., 2019) |
Metals: | |||||
Silver nanoparticles-deposited f-CNT with an amphiphilic poly(propyleneimine) dendrimer (MWCNTs-APPI-AgNPs) |
MWCNT | Drug delivery Bioimaging Medical devices |
B. subtilis E. coli S. aureus |
f-MWCNTs-AgNPs showed an inactivation percentage of 99.8% ± 0.2%, 99.7% ± 0.1%, and 93.1% ± 0.5%, for B. subtilis, S. aureus, and E. coli, respectively | (Murugan and Vimala, 2011) |
Silver sulfide quantum dots (Ag2S) | MWCNT | Antimicrobial surfaces |
E. coli P. aeruginosa S. aureus |
The bacteria killing ability of f-MWCNT-Ag2S was 97.8% ± 2.1%, 78.5% ± 2.9%, and 55.7% ± 1.5% for E. coli, P. aeruginosa, and S. aureus, respectively | (Neelgund et al., 2012) |
AgNP-decorated c-CNT | MWCNT | Nonspecified |
Methylobacterium spp. Sphingomonas spp. |
Ag-MWCNT (40 or 50 μg/mL) completely inhibited bacterial growth | (Seo et al., 2014) |
Silver and copper nanoparticles | MWCNT | Medical devices | E. coli | Ag-MWCNT and Cu-MWCNT exhibited 97% and 89% growth inhibition against E. coli, respectively | (Mohan et al., 2011) |
Copper nanoparticles | MWCNT | Nonspecified | Gram-positive and -negative bacteria; Fungi | Cu-MWCNT showed an enhanced inhibitory effect when compared with MWCNT | (Yallappa et al., 2016) |
Titanium oxide-gold (TiO2-Au) | MWCNT | Drug delivery | A broad range of Gram-positive and -negative bacteria | More than 90% biofilm inhibition was observed in the presence of TiO2-Au-MWCNT | (Karthika et al., 2018) |
Titanium dioxide (TiO2) | MWCNT | Antimicrobial agents |
E. coli S. aureus |
TiO2-MWCNT displayed high antimicrobial activity against both bacteria, as demonstrated by the diameter of inhibition zones (≥18 mm) | (Sukkar et al., 2019) |
Cadmium quantum dots (CdS) | MWCNT | Antimicrobial agents |
E. coli P. aeruginosa S. aureus |
The bacteria-killing ability of f-MWCNT-CdS was 87.2% ± 4.1%, 68.9% ± 2.5%, and 46.7% ± 1.4% against E. coli, P. aeruginosa, and S. aureus, respectively | (Neelgund et al., 2012) |
Polymers: | |||||
Amphiphilic poly(propyleneimine) Dendrimer (APPI) |
MWCNT | Drug delivery Bioimaging Medical devices |
B. subtilis E. coli S. aureus |
MWCNTs-APPI hybrid inhibited bacterial growth by 96.6% ± 0.3%, 96.5% ± 0.2%, and 87% ± 0.5% for B. subtilis, S. aureus, and E. coli, respectively | (Murugan and Vimala, 2011) |
Other compounds: | |||||
Antibodies to group A Streptococcus (GAS) | MWCNT | Antimicrobial agents | Streptococcus pyogenes | GAS-MWCNT induced 97%–100% killing of planktonic cells, depending on the time of laser exposure, and 99.99% killing of bacteria in biofilm | (Levi-Polyachenko et al., 2014) |
Pyrazole and pyrazolone derivates | MWCNT | Antimicrobial agents |
S. aureus B. subtilis E. coli C. albicans A. niger |
The antibacterial activity of MWCNTs conjugated with pyrazole derivates ranged between 17.5% and 95.2% | (Metwally et al., 2019) |
Mannose derivates | SWCNT | Anti-adhesive agents | Uropathogenic E. coli |
Mannose derivate-SWCNT induced a considerable reduction in the CFU (around 50%) when compared with the control | (Romero-Ben et al., 2019) |
APT, antimicrobial photodynamic therapy; AMP, antimicrobial peptide; MWCNT, multi-walled carbon nanotubes; SWCNT, single-walled carbon nanotubes; CFU, colony forming unit.