Polymer Multilayers that Promote the Rapid Release and Contact Transfer of DNA

Abstract

We report a layer-by-layer approach to the fabrication of thin polymer-based multilayers that release DNA rapidly in physiologically relevant environments. This approach exploits the properties of a weak anionic polyelectrolyte [poly(acrylic acid); PAA] to disrupt ionic interactions and promote disassembly in coatings that otherwise erode slowly. We investigated this approach using multilayers fabricated from plasmid DNA and linear poly(ethylenimine) (LPEI), a model synthetic cationic polymer used widely for DNA delivery. LPEI/DNA multilayers erode and release DNA slowly over ∼4 days when incubated in PBS buffer. In contrast, substitution of every other layer of DNA with PAA lead to thin films that released DNA rapidly, with >60% being released in the first 5 min. These quick-release coatings release bioactive DNA and can be used to fabricate uniform coatings on a variety of objects, including the tips of inflatable balloon catheters. We demonstrate that these coatings can promote high levels of cell transfection in vitro and the robust contact transfer and expression of DNA in vascular tissue in vivo using a rat model of vascular injury. These materials provide useful alternatives to multilayers and other coatings that promote the prolonged release of DNA. More broadly, approaches that depart from the use of degradable polymers to promote film erosion create opportunities to design new gene delivery coatings using a broader range of polymer-based building blocks designed for other gene delivery applications. With further development, this approach could thus provide a new and useful platform for the rapid contact transfer of DNA to cells and tissues of interest in a range of fundamental and applied contexts.

Electrostatically Assembled Multilayered Films of Biopolymer Enhanced Nanocapsules for on-Demand Drug Release

“…The release rate of entrapped active agents from capsule containing LbL films was remarkably lower than that of the homopolymer based multilayer films from other reports. 63,64 Binding of SNCs to CS within the LbL films and biopolymer coatings significantly enhanced entrapment of fulvestrant within the core of the SNCs and slowed down its diffusion out of the multilayer films. The release of only ∼6% of fulvestrant was observed in the first 10 day.…”

Bioactive nanocomposite coatings under visible light illumination promoted surface-mediated gene delivery

“…23 Various external driven forces, including those generated by changes of pH, temperature, electrical current/voltage and light intensity have been explored to promote the fast gene release. [24][25][26][27][28][29] For efficient cellular uptake of gene, most studies are focused on optimization of various viral or non-viral vectors, so that a balance between high delivery efficiency and safety could be reached. Alternatively, physical enhancement methods, such as electroporation, sonoporation and photoporation, have been widely investigated to promote cellular uptake of genes, through enhancing cell membrane permeability.…”

Key parameters for enhancing the thermoelectric power factor of PEDOT:PSS/PANI-CSA multilayer thin films

“…In the LBL process, the alternate polymers are adsorbed onto each other via hydrogen bonding, hydrophobic or covalent interactions. [1][2][3][4] Our group and others have used this technique to fabricate multilayer (ML) thermoelectric (TE) thin lms exhibiting an enhanced thermoelectric power factor (P). The multilayer thin lms mostly comprise sequentially deposited polymers as well as polymer/inorganic hybrids.…”