New gluconamide-type cationic surfactants: Interactions with DNA and lipid membranes

- New cationic glucose-derived CnGAB surfactants are synthesized using green chemistry.
- Compaction of DNA with CnGAB is studied by fluorescence correlation spectroscopy.
- Interactions of CnGABs with DPPC liposomes are studied by DSC and spectroscopy.
- Theoretical modeling of interaction properties of the surfactants is presented.
- C16GAB is a promising candidate as a component of gene-delivery carrier systems.

New linear cationic surfactants - 2-(alkyldimethylammonio)ethylgluconamide bromides, denoted as CnGAB, n = 10, 12, 14 and 16 - were synthesized from natural resources and characterized with respect to their potential as gene-delivery agents in gene therapy applications. Interactions with plasmid DNA and with model membranes were studied both experimentally and theoretically. The compounds with n = 12, 14 and 16 show exponentially increasing ability to fully condense DNA. C16GAB condenses DNA at 1:1 surfactant to nucleotide molar ratio. Furthermore, CnGABs interact with model membrane, slightly lowering the temperature of the main phase transition Tm of the DPPC bilayer. C10GAB is found to interact only at the membrane surface. C16GAB reduces Tm less than C12GAB and C14GAB, and forms domains in the bilayer at the surfactant/DPPC molar ratio of 0.1 and higher. The results suggest that C16GAB can be a promising candidate for building gene-delivery carrier systems.