(a) Cytotoxicity assay
of cells incubated with sampleA@PEG (5, 10, and 20 kDa) at different
time points. Growth rates were plotted as relative increase compared
to 0 h. Values are represented as the mean and standard error of the
mean of three independent experiments. Gene expression analysis of
(b) CLTC and (c) CAV1 in cells incubated
with sampleA@PEG (5, 10, and 20 kDa) at different time points. Expression
was calculated relative to the housekeeping gene RPLP0 and values
were plotted as relative changes compared to 0 h. Values are represented
as the mean and standard error of the mean of three independent experiments.
*p < 0,05, **p < 0,01; paired
Student’s t test. (d) Cellular uptake kinetics
of sampleA@PEG (5, 10, and 20 kDa) based on CAV1 gene
expression, the uptake mean-life is calculated by curve fitting using
an exponential function. Representative TEM images corresponding to
incubation times of (e) 2, (f) 8, and (g) 48 h. Arrowheads: red, FM-NPs;
blue, cell surface; and green, endosome. Scale bars 200 nm.