Cellular localization of carbon nanomaterials in cancer
cells is
essential information for better understanding their interaction with
biological targets and a crucial factor for further evaluating their
biological properties as nanovehicles or nanotherapeutics. Recently,
increasing efforts to develop promising fullerene nanotherapeutics
for cancer nanotechnology have been made. However, the main challenge
regarding studying their cellular effects is the lack of effective
methods for their visualization and determining their cellular fate
due to the limited fluorescence of buckyball scaffolds. Herein, we
developed a method for cellular localization of nonfluorescent and
water-soluble fullerene nanomaterials using the
in vitro
click chemistry approach. First, we synthesized a triple-bonded
fullerene probe (TBC
60
ser), which was further used as a
starting material for 1,3-dipolar cycloaddition using 3-azido-7-hydroxycoumarin
and sulfo-cyanine5 azide fluorophores to create fluorescent fullerene
triazoles. In this work, we characterized the structurally triple-bonded
[60]fullerene derivative and confirmed its high symmetry (
T
h
) and the successful formation
of fullerene triazoles by spectroscopic techniques (i.e., ultraviolet–visible,
fluorescence, and Fourier transform infrared spectroscopies) and mass
spectrometry. The created fluorescent fullerene triazoles were successfully
localized in the MCF-7 breast cancer cell line using fluorescent microscopy.
Overall, our findings demonstrate that TBC
60
ser localizes
in the lysosomes of MCF-7 cells, with only a small affinity to mitochondria.