Polyelectrolyte-complex multilayer membrane with gradient porous structure based on natural polymers for wound care

Chitosan and alginate have been considered to be promising natural polymers for biomedical application because of their biocompatibility, biodegradability and similarity to macromolecules recognized by human body, which are extensively used in wounds and burns management. Here a sponge-like polyelectrolyte-complex multilayer membrane (PCMM) was prepared via freeze-drying method. The attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FE-SEM) analysis revealed that chitosan/alginate layer exhibited gradient porous structure and interpenetrating polymer networks in PCMM. The porosity and swelling ratio of PCMM were evaluated. The results indicate that the prepared PCMM shows porosity up to 90% and equilibrium swelling ratio up to 22.4 in deionized water as well as 21.5 in ion-containing solution. Antibacterial activity evaluated in vitro shows the PCMM appears obviously antibacterial activity towards E. coli. Cytotoxicity study evaluated in vitro illustrates the nontoxic nature of the PCMM, and it is good for the cell attachment, growth, and proliferation. These results strongly support the possibility of using this novel PCMM for wound care.