Interaction of cationic bilayer fragments with a model oligonucleotide

Abstract

The interaction between cationic bilayer fragments and a model oligonucleotide was investigated by differential scanning calorimetry, turbidimetry, determination of excimer to monomer ratio of 2-(10-(1-pyrene)-decanoyl)-phosphatidyl-choline in bilayer fragment dispersions and dynamic light scattering for sizing and zeta-potential analysis. Salt (Na₂HPO₄), mononucleotide (2'-deoxyadenosine-5'-monophosphate) or poly (dA) oligonucleotide (3'-AAA AAA AAA A-5') affected structure and stability of dioctadecyldimethylammonium bromide bilayer fragments. Oligonucleotide and salt increased bilayer packing due to bilayer fragment fusion. Mononucleotide did not reduce colloid stability or did not cause bilayer fragment fusion. Charge neutralization of bilayer fragments by poly (dA) at 1:10 poly (dA):dioctadecyldimethylammonium bromide molar ratio caused extensive aggregation, maximal size and zero of zeta-potential for the assemblies. Above charge neutralization, assemblies recovered colloid stability due to charge overcompensation. For bilayer fragments/poly (dA), the nonmonotonic behavior of colloid stability as a function of poly (dA) concentration was unique for the oligonucleotide and was not observed for Na₂HPO₄ or 2'-deoxyadenosine-5'-monophosphate. For the first time, such interactions between cationic bilayer fragments and mono- or oligonucleotide were described in the literature. Bilayer fragments/oligonucleotide assemblies may find interesting applications in drug delivery.

Structural insights on biologically relevant cationic membranes by ESR spectroscopy

“…The coexistence of phases at low temperatures was later confirmed by 1 H-nuclear magnetic resonance (Cocquyt et al 2004) and is consistent with DSC data that show a large decrease in transition enthalpy for sonicated membranes, thereby suggesting the absence of large regions of DODAB in the gel phase (Cocquyt et al 2004;Rozenfeld et al 2011). These fluid Fig.…”

“…7). The sonicated bilayer fragments are also polydisperse, but have mean hydrodynamic sizes around 90 nm (Vieira et al 2006;Rozenfeld et al 2011).…”

Positively charged supported lipid bilayer formation on gold surfaces for neuronal cell culture

“…48 An explanation might be that the electrostatic interaction in basic conditions might be reduced due to the screening of the positive charge of DOTAP by HPO 4 2À since this divalent counter ion (the dominant anionic ion in PBS) might effectively bind to DOTAP. 53,54 Moreover, these counter ion might also generate an entropic repulsion when vesicles approach the gold surface as reported by Zhu et al 55 These effects might weaken the electrostatic adhesion force of the lipid to the surface.…”

The Versatile Dioctadecyldimethylammonium Bromide

“…DODAB remarkable interactive capability with opposite charges of silica particles [20][21][22][23], silicon wafers [24], polymeric particles [25][26][27][28][29][30][31]; polymer films [32][33][34], drugs [35][36][37][38][39][40][41][42][43][44][45], nucleic acids [31,46], oligonucleotides [47][48][49], proteins [30,[50][51][52][53][54], peptides [9,[55][56][57], polyelectrolytes [8,9,36,58,59] and many other important surfaces, biological cells, molecules and nanostructures [60][61][62]…”