*3.9. Protection Against Nuclease Degradation*

The S1 nuclease completely degraded OND in an aqueous solution of naked OND (data not shown). Dispersions of both nonloaded SEDDS in the aqueous solution of naked OND showed the same pattern. This confirmed that neither the composition of Citrem SEDDS nor Standard SEDDS interfered with the activity of the enzyme.

If OND becomes cleaved by a nuclease, short OND fragments are detected in the supernatant that do not precipitate into pellets. The amount of OND that remain intact upon contact with the S1 nuclease was detected in the pellets and is shown in Table 7. There was a significant difference in the amount of OND protected by the Citrem and Standard SEDDS, as the Standard SEDDS showed about 3.5-fold higher protection (*p* < 0.001). On the other hand, no difference was observed between DDAB-OND and DOTAP-OND in any of the SEDDS.

**Table 7.** Percentage of OND protected from degradation after 30 min of incubation in the presence of the S1 nuclease.


\*\*\* *p* < 0.001 is the statistically significant difference between Citrem and Standard SEDDS. Data are presented as mean ± SD (*n* = 3).
