FIG. 4.

Fluorescent images of individual puncta, each corresponding to a gpa-3 mRNA molecule in the neuronal cells. (a) and (b) On-chip probe delivery by the ICP-based ion pump in the same worm after (a) 4 h and (b) 24 h. (c) and (d) Off-chip diffusion-dominated delivery. (c) Individual puncta were not resolved after 4 h of off-chip incubation. (d) Puncta are visible only after 24 h of off-chip incubation. White arrows are added to aid puncta visualization. (e) Signal-to-noise ratio (SNR) of the puncta at each condition. The dotted line corresponds to the minimum value acceptable (SNR = 7). (f) Signal-to-background ratio of each punctum at each condition. An unpaired, two-tailed T test was performed (**P < 0.01, *P < 0.05; ns, not significant).