Novel degradable biointerfacing nanocomposite coatings for modulating the osteoblast response

Abstract Design and functionalization strategies for bio-functional coatings based on biodegradable and biocompatible materials intended to be employed for targeting cells activity and enhancing the bio-response are essential for both research and clinical applications. Active compounds such as ceramics and/or proteins are used for enhancing cellular response. In the last years, recent studies showed that the distribution of ceramic nanoparticles such hydroxyapatite (HA) and Lactoferrin (LF) presence have significant influence for nano-composites interfaces for osteoblast response envisaging osseous implant application. Therefore, this work is focused on embedding HA spherical nanoparticles and lactoferrin (LF) within synthetic biodegradable copolymers Poly(ethylene glycol)- block -poly(e-caprolactone) methyl ether (PEG-block-PCL Me) for the preparation of new nanocomposites coatings targeting the modulated response of osteoblast cells (i.e adhesion, mineralization). The controlled incorporation of HA and LF within the synthetic copolymeric substrates was performed by matrix assisted pulsed laser evaporation (MAPLE) method using a modular target system. The resulting morphologies and the main features were studied by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Fourier Transform Infrared Spectroscopy (FTIR) data demonstrates that the functional groups in the MAPLE-deposited films remain intact for the individual compounds and that LF was not affected by the solvents used for copolymer. The bio-functionality of the coatings has been tested using the correlated characteristics of the coatings with MC3T3-E1 murine osteoblasts response in vitro . The results clearly revealed that the coatings with HA and LF incorporated in the polymeric matrix have enhanced stability as compared with single element coatings, and that the osteoblast behavior (cell adhesion/morphology, proliferation and matrix mineralization) was differentially influenced by the variations in the physicochemical characteristics of materials surface polymeric layers.