Novel N,N’-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids for gene delivery – synthesis, in vitro transfection activity, and physicochemical characterization

Content:

This study details the synthesis and comprehensive evaluation of novel N,N’-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids designed for gene delivery. The research focuses on elucidating the structure-activity relationships governing potent non-viral gene delivery and expression. Physicochemical characterization involved lamellar assemblies with and without plasmid DNA, exploring structural requirements for effective gene delivery. The highest in vitro transfection efficiencies were observed with dimyristoyl, dipalmitoyl, and dioleoyl derivatives, particularly at a charge ratio of +/-4:1, without the need for helper lipids. The study also investigated the impact of helper lipids and cholesterol, finding that the dioleoyl derivative maintained reporter gene expression and showed increased lipofection activity at a lower charge ratio. Techniques such as dynamic light-scattering, electrophoretic mobility, Langmuir film balance, and fluorescence polarization were employed to understand the properties of these cationic lipids and their complexes. The findings suggest that well-hydrated, highly elastic cationic lipids with increased acyl chain fluidity and minimal cytotoxicity are crucial for high transfection activity.

Table of Contents:

• Keywords
• Correspondence
• Novel N,N’-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids for gene delivery – synthesis, in vitro transfection activity, and physicochemical characterization
• Abbreviations
• Experimental procedures
• Materials
• Synthesis
• Bis-(2-dimethylamino-ethyl)-amine
• 1,3-Dimyristoylamidopropan-2-ol and 1,3-dimyristoylamidopropane-2-(p-nitrophenyl) carbonate
• 1,3-Dimyristoylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate (1,31b2)
• 1,3-Dilauroylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate (1,31b1)
• 1,3-Dihexanoylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate (1,31b3)
• 1,3-Distearoylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate (1,31b4)
• 1,3-Dioleoylamidopropane-2-[bis-(2-dimethylaminoethane)] carbamate (1,31b5)
• Plasmids
• Lipid dispersions and lipoplexes
• In vitro transfection studies
• Lipid-mixing studies
• Acknowledgements
• References