Long-term biophysical stability of nanodiamonds combined with lipid nanocarriers for non-viral gene delivery to the retina.

Biophysical evaluation study of the effect of the combined nanodiamonds with niosome as non-viral vectors over time in terms of physicochemical features, cellular internalization, cell viability and transfection efficiency both in vitro and in vivo in mouse retina. [Display omitted] • Nanodiamonds can integrate into niosomes (nanodiasomes) and bind DNA (nanodiaplexes) • Nanodiasomes are physicochemically more stable over time than niosomes. • Both formulations maintain their transfection efficiency over time. • Transfection efficiency is almost 4-fold higher for nanodiaplexes compared to nioplexes. • Nanodiaplexes maintain their gene delivery capacity for 30 days in central nervous primary cell cultures and after in vivo retinal injections. Nanodiamonds were combined with niosome, and resulting formulations were named as nanodiasomes, which were evaluated in terms of physicochemical features, cellular internalization, cell viability and transfection efficiency both in in vitro and in in vivo conditions. Such parameters were analyzed at 4 and 25 °C, and at 15 and 30 days after their elaboration. Nanodiasomes showed a particle size of 128 nm that was maintained over time inside the ± 10% of deviation, unless after 30 days of storage at 25 °C. Something similar occurred with the initial zeta potential value, 35.2 mV, being both formulations more stable at 4 °C. The incorporation of nanodiamonds into niosomes resulted in a 4-fold increase of transfection efficiency that was maintained over time at 4 and 25 °C. In vivo studies reported high transgene expression of nanodiasomes after subretinal and intravitreal administration in mice, when injected freshly prepared and after 30 days of storage at 4 °C. [ABSTRACT FROM AUTHOR]