Figure 3. Confirmation of nanoneedles insertion into live cells.

(a) XY (left) and YZ (right) CLSM images of MB-modified nanoneedle arrays 10 min after insertion into HEK293 cells. (b) Time course of the relative fluorescence intensities of nanoneedles following insertion into the cell. Background fluorescence intensity is subtracted in each plot. Initial fluorescence of the nanoneedle is represented as relative fluorescence intensity of ‘1’. n = 4 for each condition. Two-sided Student’s t-test was performed on the data at the time point of 10 min. *P = 0.019, **P = 0.0014. Error bars are SD. Scale bars in (a) are 10 μm.