Influence of DNA condensation state on transfection efficiency in DNA/polymer complexes: An AFM and DLS comparative study

• Published in: Journal of biotechnology Vol. 125; no. 1; pp. 11 - 21
• Main Authors: Volcke, C., Pirotton, S., Grandfils, Ch, Humbert, C., Thiry, P.A., Ydens, I., Dubois, P., Raes, M.
• Format: Journal Article Web Resource
• Language: English
• Published: Lausanne Elsevier B.V 20.08.2006; Amsterdam Elsevier; New York, NY Elsevier Science Bv
• Subjects: Animals; Atomic force microscopy; Biological and medical sciences; Biotechnologie; Biotechnology; Cercopithecus aethiops; Chemical Physics; Condensed Matter; COS Cells; DNA; DNA - chemistry; DNA - genetics; Dynamic Light Scattering; Fundamental and applied biological sciences. Psychology; Gene therapy vehicle; Life sciences; Light; Materials Science; Methacrylates - chemistry; Microbiologie; Microbiology; Microscopy, Atomic Force - methods; Optics; Physics; Plasmids - chemistry; Plasmids - genetics; Polyethylene Glycols - chemistry; Polymers - chemistry; Scattering, Radiation; Sciences du vivant; Transfection - methods; Atomic force microscopy; Gene therapy vehicle; DNA; Dynamic Light Scattering; Transfection; Dynamics; Efficiency; Light scattering; Polymer; Gene therapy; Complexes; Comparative study
• ISSN: 0168-1656; 1873-4863; 1873-4863
• DOI: 10.1016/j.jbiotec.2006.02.010

Atomic force microscopy (AFM) is used to describe the formation process of polymer/DNA complexes. Two main objectives of this research are presented. The first one is to apply AFM as an effective tool to analyse DNA molecules and different polycation/DNA complexes in order to evaluate their degree of condensation (size and shape). The other one is to search for a relationship between the condensation state of DNA and its transfection efficiency. In this study, linear methacrylate based polymers and globular SuperFect polymers are used in order to induce DNA condensation. Ternary complexes, composed of methacrylate based polymers and polyethylene glycol (PEG)-based copolymers, are also investigated. AFM allows us to confirm good condensation conditions and relate them (or not) to transfection efficiencies. These AFM results (obtained after drying in air) are compared with measurements deduced from Dynamic Light Scattering (DLS) experiments performed in water. This comparison allowed us to identify the structural modifications resulting from deposition on the mica surface.