According to a new research study, SouthWest NanoTechnologies’ (SWeNT) single-wall carbon nanotubes (SWNTs) show absorption
of indocyanine green (ICG) — a functional dye with unique photomechanical,
photochemical, and photobiological properties.
The ICG-SWNT
complexes formed are sensitive to a broad spectrum of light, ranging from
ultraviolet (UV) to near infrared (NIR), which may help unlock this novel
nanosystem for use in potential applications in photothermal cancer therapies. In a study published in Journal of X-Ray Science and
Technology, researchers in China showed that, based on the ICG-SWT complexes
sensitivity to a broad spectrum of light, “it is expected that an effective
phototherapy is not limited to a single light source.”
“Photothermal
therapy has been attracting greater attention,” according to the authors. Usually only a laser of single wavelength has been used, such as 808 nm, 980 nm or
1064 nm in treatments. Recently, it was shown that a 658 nm laser within natural
light spectrum coupled with nanoparticles could cause irreversible photothermal
damage to tumors. However, with
the increased concentration of SWNTs increase in our experiments, typical
absorption peaks of ICG monomer (at 780 nm) or dimer (at 700 nm) were decreased
and typical absorption peak of SWNT (at 1030 nm) was increased.
The researchers
demonstrate that the absorption of ICG at 700 nm and 780 nm transformed the light
affected SWNTs in the range of UV to NIR regions. As a
result, the increased absorption of SWNTs from UV to
the NIR regions opens this novel nanosystem to potential applications in the
photothermal cancer treatment.
The research was
supported by the National Basic Research Program of China, the Program for
Changjiang Scholars and Innovative Research Team in University and the National
Natural Science Foundation of China.