Wound Healing Attributes of Polyelectrolyte Multilayers Prepared with Multi-l-arginyl-poly-l-aspartate Pairing with Hyaluronic Acid and γ-Polyglutamic Acid

Biodegradable multi-l-arginyl-poly-l-aspartate (MAPA), more commonly cyanophycin, prepared with recombinantEscherichia colicontains a polyaspartate backbone with lysine and arginine as side chains. Two assemblies of polyelectrolyte multilayers (PEMs) are fabricated at three different concentration ratios of insoluble MAPA (iMAPA) with hyaluronic acid (iMAPA/HA) and with gamma-polyglutamic acid (iMAPA/gamma-PGA), respectively, utilizing a layer-by-layer approach. Both films with iMAPA and its counterpart, HA or gamma-PGA, as the terminal layer are prepared to assess the effect on film roughness, cell growth, and cell migration. iMAPA incorporation is higher for a higher concentration of the anionic polymer due to better charge interaction. The iMAPA/HA films when compared to iMAPA/gamma-PGA multilayers show least roughness. The growth rates of L929 fibroblast cells on the PEMs are similar to those on glass substrate, with no supplementary effect of the terminal layer. However, the migration rates of L929 cells increase for all PEMs. gamma-PGA incorporated films impart 50% enhancement to the cell migration after 12 h of culture as compared to the untreated glass, and the smooth films containing HA display a maximum 82% improvement. The results present the use of iMAPA to construct a new layer-by-layer system of polyelectrolyte biopolymers with a potential application in wound dressing.