Novel cationic tannin/glycosaminoglycan-based polyelectrolyte multilayers promote stem cells adhesion and proliferation

Modifying materials with biocompatible surface coatings is an important method for controlling cell responses to biomaterials. In this work, tanfloc (TN), a cationic tannin-derivative polymer was assembled with heparin (HEP) and chondroitin sulfate (CS), using the layer-by-layer (LbL) approach, to build polyelectrolyte multilayers (PEMs) and to design cytocompatible coatings. LbL deposition was monitored through Fourier-transform surface plasmon resonance, and characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle measurements. The response of human adipose-derived stem cells (ADSCs) was evaluated in vitro. All of the TN-containing PEMs exhibit cytocompatibility and support adhesion, proliferation, and the spreading of ADSCs after 7 days of culture. HEP-TN PEM assembly with 11 layers (HEP-TN11) supports the greatest rate of cell proliferation. When TN is the terminal layer of the PEM, the surfaces promote the spreading of ADSCs, indicating that the surface charge and PEM terminal layer are key determinants of the microenvironmental niche that control cellular response. The promotion of stem cell attachment and proliferation makes these surface coatings potentially useful for biomedical implants and regenerative medicine.