Marc Sauer

Virus-assisted loading of polymer nanocontainer

We present a DNA-containing polymeric nanocontainer using the self-assembled superstructure of amphiphilic block copolymers in aqueous solutions. To demonstrate that DNA translocation is possible across a completely synthetic block copolymer membrane, we have used a phage transfection strategy as a DNA-transfer model system. For this purpose the bacterial channel forming protein LamB was reconstituted in ABA-triblock copolymer vesicles. The outer membrane protein LamB is a specific transporter for maltodextrins but also serves as a receptor for λ phage to trigger the ejection of λ phage DNA. We demonstrate that the functionality of the LamB protein is fully preserved despite the artificial surrounding. This leads to a type of polymeric vehicle for DNA that could be useful for gene therapy.

pH‐Sensitive Nanocontainers

Water‐soluble polyelectrolyte nanocapsules can be synthesized by vesicular or emulsion polymerization via core–shell latexes. These particles show a reversible pH‐ and ionic strength‐dependent swelling transition causing a considerable increase (decrease) of their radius. During this transition gated pores are opened (closed) in the spherical polymer shells, which enable free molecular exchange between the interior of the hollow sphere and the bulk medium. This pH‐switchable control of the permeability of the polyelectrolyte envelopes can be used to trigger the release of encapsulated materials from their central cavity.

Ion-carrier controlled precipitation of calcium phosphate in giant ABA triblock copolymer vesicles

An ionophore assisted metal-ion transport across block copolymer membranes has been used to control the local Ca2+ concentration during precipitation of calcium phosphate in giant block copolymer vesicles.