(A) Schematic presentation of the chemodynamic treatment
of an
MDA-MB-231 cancer cell using targeting AS1411 aptamer-functionalized
pA-AuNPs, a ROS-generating nanozyme. (B) Temporal imaging of ROS intermediates
generated in (a) epithelial MCF-10A breast cells treated with pA-AuNPs
(lacking the AS1411 aptamer), (b) epithelial MCF-10A breast cells
treated with the AS1411 aptamer conjugated to the pA-AuNPs, (c) MDA-MB-231
breast cancer cells treated with the pA-AuNPs (lacking the AS1411
aptamer units), and (d) MDA-MB-231 breast cancer cells treated with
the AS1411 aptamer conjugated to the pA-AuNPs. In all experiments,
cells were treated with 5 nM of the respective NPs. (C) Time-dependent
integrated fluorescence intensities of ROS products generated by (a)
MCF-10A cells treated with pA-AuNPs, (b) MCF-10A cells treated with
AS1411/pA AuNPs conjugate, (c) MDA-MB-231 cancer cells treated with
pA-AuNPs, and (d) MDA-MB-231 cancer cells treated with AS1411/pA-AuNPs
conjugate. Fluorescence was generated by staining the respective cells
with di(acetoxymethyl ester)-6-carboxy-2′,7′-dichlorodihydrofluorescein
diacetate (C-DCDHF-DA). Error bars derived by analyzing N = 4 frames of cells. (D) Cell viability of MCF-10A epithelial breast
cells (green columns) and MDA-MB-231 breast cancer cells (red columns)
treated with (a) control system consisting of untreated cells; columns
(b1), (b2), and (b3) correspond to treatment of the cells for 2 days
with pA-AuNPs (non-aptamer conjugates) using doses corresponding to
0.9 nM, 1.2 nM, and 1.5 nM, respectively, and columns (c1), (c2),
and (c3) correspond to cells treated with the AS1411/pA-AuNPs conjugates
using doses corresponding to 0.9 nM, 1.2 nM, and 1.5 nM.