Cellular fate of oligonucleotides when delivered by nanocapsules of poly(isobutylcyanoacrylate)

Dual-labeled phosphorothioate oligonucleotides were encapsulated in the internal aqueous core of poly(isobutylcyanoacrylate) nanocapsules with high yields. Intracellular distribution of naked and encapsulated oligomers was assessed on cultured vascular smooth muscle cells using cell fractionation and confocal microscopy methods. The results showed that cell uptake and more interestingly, nuclear accumulation of oligonucleotides were importantly enhanced when the oligonucleotides were associated to the nanocapsules as compared to the naked oligomers. These results suggested an efficient capacity of this polymeric carrier to deliver its payload to the cytosol and nucleus of smooth muscle cells.