Figure 4.
(A) Photothermal effect of PEGylated MGNRs@DMSSs aqueous solution at different Au concentrations with NIR laser irradiated (808 nm, 1.5 W cm−2) for 5 minutes. (B) Photothermal stability of PEGylated MGNRs@DMSSs with Au concentration of 0.135 mg/mL during five cycles of 808 nm NIR laser irradiation (1.5 W/cm2) for 300 seconds and cooling down for 600 seconds. (C) Confocal microscopic images of SMMC-7721 cells treated with different groups: (C1) control group, (C2) laser irradiation only, (C3) PEGylated MGNRs@DMSSs only, and (C4) PEGylated MGNRs@DMSSs with laser irradiation (all images were stained with calcein AM and PI, where green fluorescence from calcein AM and red fluorescence from PI indicate live and dead cells, respectively). Scale bars are 200 µm. (D) Relative cell viabilities of SMMC-7721 cells after 24 hours incubation with PEGylated MGNRs@DMSSs and PEGylated GNRs at different Au concentrations with or without laser irradiation. (E) Flow cell apoptosis of SMMC-7721 cells treated with different groups, where green fluorescence from Annexin V-FITC and red fluorescence from PI indicate live and dead cells, respectively.
Abbreviations: PEGylated MGNRs@DMSSs, mPEG-silane (Mw =5,000) modified multiple gold nanorices in dual-mesoporous silica nanospheres; NIR, near-infrared; AM, acetoxymethyl; PI, propidium iodide.