Cationic lipids containing protonated cyclen and different hydrophobic groups linked by uracil-PNA monomer: Synthesis and application for gene delivery

In this report, as candidates for non-viral gene vectors, cationic lipids L1, L2 and L3 based on protonated cyclen and different hydrophobic groups (cholesterol, dodecanol or diosgenin) linked by PNA monomer were designed and synthesized. Their liposomes were easily prepared by mixing the synthesized lipids with dioleoylphosphatidyl ethanolamine (DOPE) under appropriate mole ratios. Agarose gel retardation and fluorescent titration by ethidium bromide (EB) showed the strong DNA-binding ability with the Ksv values of 1.21 × 107, 3.76 × 106 and 2.90 × 106 M−1 for the liposomes formed from L1–L3, respectively. These liposomes could retard pDNA at an N/P ratio of 3 and form lipoplexes with sizes around 200–300 nm and zeta-potential values of +20–50 mV at N/P ratio from 4 to 10. Besides, the cytotoxicity of the three lipoplexes assayed by MTT is quite different. The results from in vitro transfection in HEK 293T and A549 cell lines showed that the transfection efficiency of L3/DOPE/DNA lipoplex at an N/P ratio of 6 and lipid/DOPE mole ratio of 1:2 is slightly higher than that of Lipofectamine 2000™, indicating that the title PNA monomer-based cationic lipids have great potential to be efficient non-viral gene vector.

Cationic lipids L1, L2 and L3 based on protonated cyclen and different hydrophobic groups (cholesterol, dodecanol or diosgenin) linked by PNA monomer showed great potential to be efficient non-viral gene vector in vitro transfection in HEK 293T and A549 cell.Figure optionsDownload as PowerPoint slideHighlights
► Three novel cyclen-based cationic lipids were designed and synthesized.
► The liposomes showed strong DNA-binding and gel retardation ability.
► DNA was condensed into nanoparticles with proper sizes and zeta-potentials.
► L3 gave higher transfection efficiency than Lipofectamine 2000 in two cell lines.