Flow cytometry
SGC-7901 cells (4.5 × 105 cells/plate) growing in six-well
plates were cultured for 24 h. Cells were divided into
eight groups—A: without nano-AE, pDNA and no light,
treated as blank control; B: pDNA group; C: nano-AE
group; D: nano-AE transfection group; E: pure light group;
F: pDNA and light group; G: nano-AE PDT group; H:
nano-AE transfection and PDT group. Groups A and E
were cultured with fresh culture RPMI 1640 medium
(1 mL) free of FBS. Groups C and G were incubated
with RPMI 1640 medium (1 mL) free of FBS with liposomes
(6 μL). Groups B, D, F, and H were incubated with the
mixture (1 mL) containing the nano-AE (6 μL) and pDNA
(2 μg). All groups were incubated for 6 h. The medium
was replaced with culture medium (2 mL) with FBS (10%)
and was cultured for 72 h. Cells were exposed (except
for the dark controls) to UV light from the LED at a
wavelength of 430 nm and an energy density of 40 mw/
cm2 for 160 sec (the final energy density of 6.4 J/cm2).
Cells were then cultured for 12 h in the dark. All cells
were harvested for Annexin V/PI double staining and
measured using a BD FACScalibur flow cytometry system
(BD Bioscience, Franklin lakes, NJ).