Single-walled carbon nanotubes (SWCNTs) are known to have great potential for biomedical applications such as photothermal ablation of tumor cells in combination with near-infrared (NIR) irradiation. In this study, the photothermal activity of a novel SWCNTs composite with a designed peptide having a repeated structure of H-(-Lys-Phe-Lys-Ala-)7-OH [(KFKA)7] against tumor cells was evaluated in vitro and in vivo. The SWCNT-(KFKA)7 composite demonstrated high aqueous dispersibility that enabled SWCNTs to be used in tumor ablation. The NIR irradiation of SWCNT-(KFKA)7 solution resulted in a rapid temperature increase dependent on the SWCNTs concentration up to 50μg/ml. Three minutes of NIR irradiation of a colon 26 or HepG2 cell culture incubated with SWCNT-(KFKA)7 resulted in remarkable cell damage, while that by single treatment with SWCNT-(KFKA)7 or NIR irradiation alone was moderate. The intratumoral injection of SWCNT-(KFKA)7 solution followed by NIR irradiation resulted in a rapid increase of the temperature to 43°C in the subcutaneously inoculated colon 26 tumor based on thermographic observation and remarkable suppression of tumor growth compared with treatment with only SWCNT-(KFKA)7 injection alone or NIR irradiation alone. These results suggest the a great potential of an SWCNT-peptide composite for use in photothermal cancer therapy.
Reactive oxygen species (ROS) are the weapon of neutrophiles against bacterial pathogens, and also the central effector in the reactive oxygen therapy for skin and soft tissue infection. Nanozymes that...
As the barrier between the human body and the outside world, the skin is vulnerable to pathogenic microorganisms, especially at the condition of skin injuries such as burns. Staphylococcus aureus...
Damage
or injury to the skin creates wounds that are vulnerable
to bacterial infection, which in turn retards the process of skin
regeneration and wound healing. In patients with severe burns and
those with chronic diseases, such as diabetes, skin infection by multidrug-resistant
bacteria can be lethal. Therefore, a broad-spectrum therapy to effectively
eradicate bacterial infection through a mechanism different from that
of antibiotics is much sought after. We successfully synthesized antibacterial
photodynamic gold nanoparticles (AP-AuNPs), which are self-assembled
nanocomposites of an antibacterial photodynamic peptide and poly(ethylene
glycol) (PEG)-stabilized AuNPs. The AP-AuNPs exhibited aqueous and
light stability, a satisfactory generation of reactive oxygen species
(ROS), and a remarkable antibacterial effect toward both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli upon light irradiation. Moreover,
the synthesized nanocomposites significantly inhibited bacterial growth
and biofilm formation in vitro. Photodynamic antibacterial
treatment accelerated the wound-healing rate in S.
aureus infections, mimicking staphylococcal skin infections.
Using a combination of the bactericidal effect of a peptide, the photodynamic
effect of a photosensitizer, and the multivalency clustering on AuNPs
for maximal antibacterial effect under light irradiation, we synthesized
AP-AuNPs as a wound-dressing nanomaterial in skin infections to promote
wound healing. Our findings indicate a promising strategy in the management
of bacterial infections resulting from damaged skin tissue, an aspect
that has not been fully explored by our peers.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.