Fig. 5
NS coupled with photothermal effect applied to cellular DNA transfection. (a) Schematic illustrating the photothermal effect of NS. (b) NIR thermal imaging and (c) photothermal curves characterizing the photothermal properties of the Au/NS. (d) Fluorescent microscopy images capturing the cell condition to various laser intensity applied to the NS. The images display the merged signals from Calcein AM (green), Hoechst (gray), and PI (red). The upper panel represents HeLa cells, the middle panel shows DC2.4 cells, and the lower panel features HL-1 cells. Different laser intensity (2.0, 3.6, 4.6, and 7.4 W/cm2) are organized in rows from left to right. (e) Cell viability assessment under varied laser intensity conditions based on microscopic images. Mean ± SEM, n = 3, One-way ANOVA. (f) Schematic of transfection by NS coupled with photothermal effect (Photothermal effect & NS). (g) Photograph displaying the cell culture device is exposed to laser irradiation. (h) GFP expression observed by microscopy post-transfection via NS coupled with photothermal effect. These images show the merged signals of GFP, Hoechst, and PI, with the rows corresponding to those in panel (d). (i) Quantification of transfection efficiency and cell viability after pMAX-GFP transfection mediated by NS coupled with photothermal effect, based on the microscopic images. Mean ± SEM, n = 3, Two-way ANOVA. Scale bars in all images are 200 μm