Gene therapy and
RNA delivery require a nanoparticle (NP) to stabilize these
nucleic acids when administered in vivo. The presence of degradative hydrolytic
enzymes within these environments limits the
nucleic acids' pharmacologic activity. This study compared the effects of nanoscale ZnO and MgO in the protection afforded to
DNA and
RNA from degradation by
DNase, serum or
tumor homogenate. For double-stranded plasmid
DNA degradation by
DNase, our results suggest that the presence of MgO NP can protect
DNA from
DNase digestion at an elevated temperature (65 °C), a biochemical activity not present in ZnO NP-containing samples at any temperature. In this case, intact
DNA was remarkably present for MgO NP after
ethidium bromide staining and
agarose gel electrophoresis where these same stained
DNA bands were notably absent for ZnO NP. Anticancer
RNA,
polyinosinic-polycytidylic acid (
poly I:C) is now considered an anti-metastatic
RNA targeting agent and as such there is great interest in its delivery by NP. For it to function, the NP must
protect it from degradation in serum and the
tumor environment. Surprisingly, ZnO NP protected the
RNA from degradation in either serum-containing media or
melanoma tumor homogenate after gel electrophoretic analysis, whereas the band was much more diminished in the presence of MgO. For both MgO and ZnO NP,
buffer-dependent rescue from degradation occurred. These data suggest a fundamental difference in the ability of MgO and ZnO NP to stabilize
nucleic acids with implications for
DNA and
RNA delivery and
therapy.