TY - JOUR
T1 - DNA-METAFECTENE (TM) PRO complexation
T2 - a physical chemistry study
AU - Alatorre-Meda, M.
AU - Pérez, Alfredo González
AU - Rodriguez, J. R.
PY - 2010/7/21
Y1 - 2010/7/21
N2 - 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.
AB - 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.
U2 - 10.1039/b920900j
DO - 10.1039/b920900j
M3 - Journal article
C2 - 20495721
SN - 1463-9076
VL - 12
SP - 7464
EP - 7472
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
IS - 27
ER -