Abstract
Complexes formed between cationic liposomes and DNA (also known as lipoplexes or genosomes) have proven, for years now, to be a suitable option for gene delivery to cells, transfection, however, some aspects regarding the liposome-DNA interaction mechanism and complex stability remain still unclear. This work aims to improve the understanding of the poorly defined mechanisms and structural conformation associated with the interaction of METAFECTENE ™ PRO (MEP), a commercial liposomal transfection reagent, with poly-anion DNA at mass ratios around the mass ratio recommended for transfection (L/D ≅ 700). A physical chemistry characterization was conducted at a pH of 6.5 and at a temperature of 25°C by means of dynamic light scattering (DLS), electrophoretic mobility (ζ-potential), transmission electron microscopy (TEM), and atomic force microscopy (AFM). Five parameters important for transfection were determined for the lipoplexes: (i) the hydrodynamic radius, RH, (ii) the stability with time, (iii) the mass ratio of at which both moieties start to interact, (L/D)i, (iv) the overall charge, and (v) the morphology. Results in ensemble point to a "beads on a string" conformation, with the lipoplex formation occurring well below isoneutrality from (L/D)i ≅ 600. The lipoplexes were found to be stable within at least seven days presenting an average RH of 135 nm.
| Original language | English |
|---|---|
| Journal | Physical Chemistry Chemical Physics |
| Volume | 12 |
| Issue number | 27 |
| Pages (from-to) | 7464-7472 |
| Number of pages | 8 |
| ISSN | 1463-9076 |
| DOIs | |
| Publication status | Published - 21 Jul 2010 |