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Published on: January 19, 2019
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Multilayered thin films from poly(amido amine)s and DNA.
Sry D Hujaya1, Johan F J Engbersen1, Jos M J Paulusse1
1Department of Controlled Drug Delivery, MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Acta Biomaterialia
|May 2, 2015
Summary
New multilayered thin films made of poly(amido amine)s (PAAs) and DNA offer cell-transfecting capabilities. These functional surfaces facilitate cell attachment, proliferation, and gene transfection without cytotoxic agent removal.
Area of Science:
- Biomaterials Science
- Surface Chemistry
- Cell Biology
Background:
- Developing efficient and non-toxic gene delivery systems is crucial for advancing cell-based therapies and research.
- Existing transfection methods often involve cytotoxic agents or complex procedures.
- Multilayered thin films offer a promising platform for controlled release of bioactive molecules.
Purpose of the Study:
- To engineer dip-coated multilayered thin films of poly(amido amine)s (PAAs) and DNA for cell-transfecting capabilities.
- To investigate the influence of PAA side chain functional groups on multilayer formation and DNA deposition.
- To evaluate the stability and cell-transfection efficiency of these functionalized surfaces.
Main Methods:
- Synthesis and characterization of three types of PAAs with varying side chain functional groups.
- Fabrication of multilayered thin films using dip-coating technique with calf thymus DNA (CTDNA).
- UV spectroscopy, atomic force microscopy (AFM), and water contact angle measurements for film characterization.
- In vitro stability studies under physiological and reductive conditions.
- COS-7 cell culture and transfection assays using plasmid DNA encoding for green fluorescence protein (GFP).
Main Results:
- All three PAAs formed linear multilayer structures with CTDNA, with higher charge density correlating to lower DNA deposition.
- AFM and contact angle measurements confirmed complete surface coverage after four layer pairs, with surface morphology dependent on the top layer.
- Films degraded in the presence of dithiothreitol (DTT) and underwent thermodynamic rearrangement releasing DNA under physiological salt conditions.
- Two of the three PAA/DNA multilayers supported good COS-7 cell attachment, proliferation, and efficient GFP transfection within 48 hours.
- Fluorescence staining confirmed the presence of released film material containing DNA among cultured cells.
Conclusions:
- Dip-coated PAA/DNA multilayered thin films can be tailored for cell-transfecting functionality.
- The films provide a stable yet releasable platform for DNA delivery, facilitating gene transfection.
- This approach enables efficient cell transfection simply by culturing cells on the functionalized surface under optimal conditions, avoiding cytotoxic agent removal.
