Figure 2. Persistence of HA-CSO NPs over time. A: For both corneal and conjunctival cells, fluorescence intensity was greatest at 1 h after incubation. By 6 h, the intensity diminished to approximately half, where it remained stable for up to 48 h. B: NP-associated fluorescence diminished with time, as fluorescence micrographs at 1, 6, 24, and 48 h after treatment show. Uptake was higher in the HCE than in the IOBA-NHC cells (n=4).